usmle med 6

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0><tr> <td valign="top" colspan=2 height=90 BGCOLOR="#006699" TEXT="#080000" bgproperties="fixed" background="02c285a1erlcgo.png"> <div> <B>usmle med 6</B></div> <bR> <div> </div> </td> </tr><tr> <td valign="top" width=210 BGCOLOR="#FFCC66" TEXT="#080000" background="02ad2c00dkelyh.png"> <div> <B>DANIL HAMMOUDI.MD</B></div> <div> <A HREF="http://SINOEMEDICALASSOCIATION.COM" TARGET="_top" TITLE="http://SINOEMEDICALASSOCIATION.COM"><U><B>SINOE MEDICAL ASSOCIATION</B></U></A></div> <div> <B>  <a href="http://counter.mycomputer.com/"><img alt="Counter" src="http://counter.mycomputer.com/c.count?u=DHAMMOUD&c=1" border=0></a>   </B></div> <div> <B>  <a href="http://htmlgear.lycos.com/specs/guest.html" target="_top"><img border="0" ismap src="http://htmlgear.lycos.com/img/guest/gb_blue.gif"></a><br> <a href="http://htmlgear.lycos.com/guest/control.guest?u=dhammoud&i=6&a=view" target="_top"><font face="arial,helv,helvetica,sans serif" size="-1">View My Guestbook</font></a><br> <a href="http://htmlgear.lycos.com/guest/control.guest?u=dhammoud&i=6&a=sign" target="_top"><font face="arial,helv,helvetica,sans serif" size="-1">Sign My Guestbook</font></a><br>   </B></div> <bR> </td> <td valign="top" height=390 BGCOLOR="#FFFFFF" TEXT="#080000"> <div> <IMG SRC="04ebc8d0.jpg" border=0 width="700" height="141" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> <A HREF="id23.htm" TARGET="_top" TITLE="pearls 1"><U>pearls 1</U></A>   |   <A HREF="id20.htm" TARGET="_top" TITLE="pearls 2"><U>pearls 2</U></A>   |   <A HREF="id21.htm" TARGET="_top" TITLE="pearls 3"><U>pearls 3</U></A>   |   <A HREF="id22.htm" TARGET="_top" TITLE="pearls 4"><U>pearls 4</U></A>   |   <A HREF="id24.htm" TARGET="_top" TITLE="pearls 5"><U>pearls 5</U></A>   |   <A HREF="id18.htm" TARGET="_top" TITLE="qcm"><U>qcm</U></A>   |   <A HREF="id19.htm" TARGET="_top" TITLE="answers"><U>answers</U></A>   |   <A HREF="id17.htm" TARGET="_top" TITLE="Contact Me"><U>Contact Me</U></A></div> <bR> <DIV ALIGN="LEFT"></DIV> <div>  <img src="HTMLobj-81/aniGif.gif" border="0" align="bottom" width="79" height="120">   <img src="HTMLobj-82/aniGif.gif" border="0" align="bottom" width="200" height="200">   <img src="HTMLobj-83/aniGif.gif" border="0" align="bottom" width="120" height="100">  </div> <bR> <div>  <img src="HTMLobj-160/aniGif.gif" border="0" align="bottom" width="120" height="120">  </div> <bR> <bR> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">With progressive deficits related to the posterior fossa (cerebellum and brain stem), a space-occupying lesion such as a tumor (medulloblastoma, ependymoma, brain-stem glioma) should be immediately excluded. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Because of the presence of bone in the posterior fossa, a magnetic resonance imaging (MRI) scan is more sensitive than a computed tomography (CT) scan. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Because of the progressive rather than acute nature, an electroencephalogram (EEG)  or drug screen  would be less likely to be diagnostic, although it might be considered in an acute process. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Aminoacidurias, detected by an amino acid screen , tend to present at an earlier age.</div> <div> ========================================================================================================</div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Munchausen syndrome occurs in those who purposefully make themselves sick in order to be admitted to the hospital. Injection of insulin to produce hypoglycemia that mimics an insulinoma is one example of this syndrome. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Because C peptide is the internal marker of endogenous insulin release, a patient with an insulinoma (benign tumor of islet cells)  would be expected to</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> have a high C peptide, </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">high serum insulin, </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">and low serum glucose. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">If the C peptide is low, the patient must be taking insulin, because exogenous insulin would lower the patient's own insulin production, therefore lowering the C peptide.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> A glucagonoma  or a somatostatinoma  would be associated with hypoglycemia.</div> <bR> <bR> <div> =======================================================================================================</div> <bR> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The findings suggest that the patient has systemic lupus erythematosus (SLE)[READ THE PATHOLOGY OF IT ON MY <A HREF="http://PATHOLOGYLECTURES.HOMESTEAD.COM" TARGET="_top" TITLE="http://PATHOLOGYLECTURES.HOMESTEAD.COM"><U>PATHOLOGY</U></A> WEBSITE].</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> <B>The serum antinuclear antibody (ANA) test is the gold-standard screening test to rule out SLE </B>and other collagen vascular diseases. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The major groups of ANA are antibodies against DNA (both double- and single-stranded), histones and nonhistone proteins, and nucleolar antigens.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> The ANA provides a titer of the antibody as well as a pattern on immunofluorescence.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> The patterns include diffuse (homogeneous), speckled, rim (peripheral), and nucleolar. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Some patterns are specific for certain diseases. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">For example, a rim pattern is usually associated with anti-double-stranded (ds) DNA, which is very specific for SLE with renal involvement. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">A nucleolar pattern is specific for progressive systemic sclerosis. </div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The two most specific antibodies (least number of false-positives) for SLE are <FONT SIZE="3" COLOR="#FF0000" FACE="Arial" ><B>anti-ds DNA (98%) and anti-Sm (Smith) [100%].</B></FONT> </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f00000ff00.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Anti-SSA (Ro)  and anti-SSB (La) are positive in Sjögren's syndrome in 70% to 95% and 60% to 90%, respectively</B><FONT SIZE="3" COLOR="#000000" FACE="Arial" >.</FONT></div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> The presence of anti-SSA (Ro) in a pregnant woman with SLE has a high association with complete heart block in newborns.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Anticentromere antibodies are present in 90% of patients with the CREST syndrome, and antiribonucleoproteins are seen in more than 95% of patients with mixed connective tissue disease.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Antimitochondrial antibodies are noted in more than 90% of cases of primary biliary cirrhosis, and antihistone antibodies are present in more than 95% of patients with drug-induced SLE (most commonly due to procainamide)</div> <bR> <div> ======================================================================================================</div> <bR> <div> <TABLE BORDER="0" CELLPADDING="1" CELLSPACING="1" WIDTH="564" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="VOID" RULES="NONE" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=CENTER HEIGHT= 76 WIDTH="560"><div> A 47-year-old homeless male alcoholic presents with a fever and expectoration of foul-smelling sputum. His dental hygiene is poor. A chest x-ray reveals a cavitary lesion with a fluid layer in the superior segment of the right lower lobe. A Gram's stain of sputum would be expected to show which of the following</div> </tD> </tR> </TABLE></div> <bR> <bR> <bR> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The patient has a lung abscess that is due to aspiration of infected material from the oropharynx. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">This condition occurs in patients who are unconscious or obtunded from alcohol. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Poor dental hygiene is invariably present. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Gram's stain classically shows a mixture of aerobic and variable-staining anaerobic organisms, consisting of gram-positive cocci and a mixture of gram-positive and gram-negative rods with tapered ends. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Common anaerobes include </div> <div> <I><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Bacteroides melaninogenicus</I> (faint gram-negative rods), </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">anaerobic streptococci (small gram-positive cocci), </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">and <I>Fusobacterium nucleatum</I> (gram-negative rods with tapered ends). </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The basilar segments of the right lower lobe are the classic location for aspiration in the upright or sitting position. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The posterior segment of the upper lobe is involved if aspiration occurs when the patient is lying on the right side. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The superior segment of the lower lobe is involved if the patient aspirates in the supine position. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Penicillin plus vigorous bronchial toilet is usually effective in the treatment of anaerobic lung abscesses. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Surgery is rarely indicated. </div> <bR> <bR> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Gram-positive diplococci in the sputum  are most commonly </B><FONT SIZE="3" COLOR="#FF0000" FACE="Arial" ><I><B><U>Streptococcus pneumoniae</U></B></I></FONT><B>, the most common community-acquired pneumonia.</B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Fat gram-negative rods with capsules  are usually </B><FONT SIZE="3" COLOR="#FF0000" FACE="Arial" ><I><B><U>Klebsiella pneumoniae</U></B></I></FONT><B>, which is commonly associated with alcoholism.</B> </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The abscesses are usually located within areas of lobar consolidation.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Gram-positive filamentous and branching bacteria in the sputum  could be <I><B>Actinomyces</B></I><B> or </B><I><B>Nocardia</B></I><B>.</B> </div> <div> <I><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Actinomyces</I> is a strict <B>anaerobe </B>and is present within sulfur granules. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">It produces pleuropulmonary disease, with sinus tracts draining pus out to the skin.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> <I>Nocardia</I> is a strict <B>aerobe</B> and is partially acid-fast. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Primary pulmonary disease with abscess formation is most commonly seen in immunocompromised hosts, particularly heart transplant patients.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Gram-positive rods (e.g., <I>Listeria</I>, <I>Clostridium</I> species, <I>Bacillus</I> species)  are not common causes of lung abscesses.</div> <bR> <bR> <div> ===========================================<B>=====================================================</B><B>===========</B></div> <div>  acute lead toxicity, which can present as </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">wristdrop in an adult </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">or as encephalopathy in a child. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">A nerve conduction velocity (NCV) study  would only confirm the clinical diagnosis, not give the cause. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">X-rays and magnetic resonance imaging (MRI) scans would give uninformative structural information. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Diabetes is the most common cause of neuropathy, but it would be very unlikely to present initially as a motor neuropathy, because it usually <B>affects sensory fibers clinically first.</B></div> <bR> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Young children have a great potential for lead exposure </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">are especially susceptible to its toxic effects.</B> </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Since blood lead readily crosses the placenta, lead poses a substantial threat to the developing fetus.</B> </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Workers may bring lead dust home on skin and clothes and unknowingly expose family members.</B> </div> <bR> <div> Hyperactivity - it's not always ADD </div> <bR> <div> Little Pika appears to have a normal exam. What clues in the history might help establish the presence of lead toxicity?</div> <bR> <div> Answer<FONT SIZE="3" COLOR="#000000" FACE="Arial" >: The usual symptoms of childhood lead poisoning (in the absence of an encephalopathy) are generally non-specific.</FONT></div> <div>  Ask about abdominal colic, behavior-attention disorders, or unexplained retardation-developmental delays</div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The incomplete development of the blood-brain barrier in very young children (up to 36 months of age) increases the risk of lead's entry into the developing nervous system, which can result in prolonged neurobehavioral disorders. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Children absorb and retain more lead in proportion to their weight than do adults.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Young children also show a greater prevalence of iron deficiency, a condition that can increase gastrointestinal absorption of lead.</div> <div> <U>Exposure Pathways</U></div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead is a naturally occurring element that has been used almost since the beginning of civilization. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Because of the many industrial activities that have brought about its wide distribution, lead is ubiquitous in the environment today.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> All humans have lead in their bodies, primarily as a result of exposure to manmade sources. </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The primary sources of environmental exposure to lead are </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">leaded paint, </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">auto emissions, </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">and drinking water</B>. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Today, the major environmental sources of metallic lead and its salts are paint, auto exhaust, food, and water. </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">For children, the most important pathways are </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">ingestion of chips from lead-painted surfaces,</B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> inhalation of lead from automobile emissions, </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">food from lead-soldered cans, drinking water from lead-soldered plumbing, </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">and medications in the form of folk remedies. </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">A wide variety of workers, hobbyists, and substance abusers may</B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">encounter potentially high levels of lead. </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Certain folk remedies may also cause lead poisoning.</B> </div> <bR> <div> Automobile emissions have been an important source of lead exposure for urban residents, particularly in areas with congested traffic. </div> <div> Although inhalation of lead from gasoline is no longer considered a public health problem, the lead from dust in automobile emissions has been deposited in the soil.</div> <div>  Children playing near roads and freeways may come in contact with contaminated soil.</div> <bR> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead enters the body primarily through ingestion and inhalation.</B> </div> <bR> <div> Sources of lead exposure</div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Occupational</B> </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Plumbers, pipe fitters </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead miners </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Auto repairers </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Glass manufacturers </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Shipbuilders </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Printers </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Plastic manufacturers </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead smelters and refiners </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Police officers </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Steel welders or cutters </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Construction workers </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Rubber product manufacturers Gas station attendants </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Battery manufacturers </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Bridge reconstruction workers </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Firing range instructors </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Environmental</B> </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead-containing paint </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Soil/dust near lead industries, roadways, lead-painted homes </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Plumbing leachate </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Ceramicware </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Leaded gasoline </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">H<B>obbies and Related Activities</B> </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Glazed pottery making </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Target shooting at firing ranges </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead soldering (e.g., electronics) </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Painting </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Preparing lead shot, fishing sinkers </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Stained-glass making </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Car or boat repair </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Home remodeling </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Substance Use</B> </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Folk remedies </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">"Health foods" </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Cosmetics </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Moonshine whiskey </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Gasoline "huffing" </div> <div> Biologic Fate</div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Once in the bloodstream, lead is primarily distributed among three compartments -- blood, soft tissue, and mineralizing tissue. </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The bones and teeth of adults contain more than 95% of total lead in the body.</B> </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">In times of stress, the body can mobilize lead stores, thereby increasing the level of lead in the blood.</B> </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The body accumulates lead over a lifetime and normally releases</B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">it very slowly.</B> </div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">In the human body, inorganic lead is not metabolized but is directly absorbed, distributed, and excreted. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The rate at which lead is absorbed depends on its chemical and physical form and on the physiologic characteristics of the exposed person (e.g., nutritional status and age).</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Inhaled lead deposited in the lower respiratory tract is completely absorbed. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The amount of lead absorbed from the GI tract of adults is typically 10% to 15% of the ingested quantity; for pregnant women and children, the amount absorbed can increase to as much as 50%. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The quantity absorbed increases significantly under fasting conditions and with iron or calcium deficiency. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Once in the blood, lead is distributed primarily among three compartments- blood, soft tissue (kidney, bone marrow, liver, and brain), and mineralizing tissue (bones and teeth).</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Mineralizing tissue contains about 95% of the total body burden of lead in adults. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The lead in mineralizing tissues accumulates in subcompartments that differ in the rate at which lead is resorbed. In bone, there is both a labile component, which readily exchanges lead with the blood, and an inert pool. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The lead in the inert pool poses a special risk because it is a potential endogenous source of lead.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> When the body is under physiologic stress such as pregnancy, lactation, or chronic disease, this normally inert lead can be mobilized, increasing the lead level in blood. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Because of these mobile lead stores, significant drops in a person's blood lead level can take several months or sometimes years, even after complete removal from the source of lead exposure. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Of the lead in the blood, 99% is associated with erythrocytes; the remaining 1% is in the plasma, where it is available for transport to the tissues. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The blood lead not retained is either excreted by the kidneys or through biliary clearance into the gastrointestinal tract. In single- exposure studies with adults, lead has a half-life, in blood, of approximately 25 days; in soft tissue, about 40 days; and in the nonlabile portion of bone, more than 25 years. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Consequently, after a single exposure a person's blood lead level may begin to return to normal; the total body burden, however, may still be elevated. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">For lead poisoning to develop, major acute exposures to lead need not occur. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The body accumulates this metal over a lifetime and releases it slowly, so even small doses, over time, can cause lead poisoning.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> It is the total body burden of lead that is related to the risk of adverse effects.</div> <bR> <div> <IMG SRC="050975c0.png" border=0 width="407" height="604" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead affects primarily the peripheral and  central nervous systems, the blood cells, and metabolism of vitamin D and calcium. </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead also causes reproductive toxicity</B>. </div> <bR> <bR> <div> <B>Neurologic Effects </B></div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The most sensitive target of lead poisoning is the nervous system. In children, neurologic deficits have been documented at exposure levels once thought to cause no harmful effects. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">In addition to the lack of a precise threshold, childhood lead toxicity may have permanent effects. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">One study showed that damage to the central nervous system (CNS) that occurred as a result of lead exposure at age 2 resulted in </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">continued deficits in neurologic development, </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">such as lower IQ scores and</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> cognitive deficits, at age 5.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> In another study that measured total body burden, primary school children with high tooth lead levels but with no known history of lead poisoning had</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> larger deficits in psychometric intelligence scores,</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> speech and language processing,</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> attention,</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> and classroom performance than children with lower levels of lead. A 1990 follow-up report of children with elevated lead levels in their teeth noted a sevenfold increase in the odds of failure to graduate from high school, lower class standing, greater absenteeism, more reading disabilities, and deficits in vocabulary, fine motor skills, reaction time, and hand-eye coordination 11 years later. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The reported effects are more likely caused by the enduring toxicity of lead than by recent excessive exposures because the blood lead levels found in the young adults were low (less than 10 micrograms per deciliter (mcg/dL)). </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Effects in children generally occur</B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">at lower blood lead levels than in adults.</B> </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The developing nervous system in children</B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">can be affected adversely at blood lead levels of less than 10 mcg/dL.</B> </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Neurologic deficits, as well as other</B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">effects caused by lead poisoning, may be irreversible.</B> </div> <bR> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Hearing acuity, particularly at higher frequencies, has been found to decrease with increasing blood lead levels.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Hearing loss may contribute to the apparent learning disabilities or poor classroom behavior exhibited by children with lead intoxication. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Adults also experience CNS effects at relatively low blood lead levels, manifested by </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">subtle behavioral changes,</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">fatigue,</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> and impaired concentration.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Peripheral nervous system damage, <B>primarily motor</B>, is seen mainly in adults. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Peripheral neuropathy with mild slowing of nerve conduction velocity has been reported in asymptomatic lead workers. </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead neuropathy is believed to be a motor neuron, anterior horn cell disease with peripheral dying-back of the axons</B>. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Frank wrist drop occurs only as a late sign of lead intoxication. </div> <bR> <bR> <div> <B>Hematologic Effects </B></div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead inhibits the body's ability to make hemoglobin by interfering with several enzymatic steps in the heme pathway. </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Ferrochelatase, which catalyzes the insertion of iron into protoporphyrin IX, is quite sensitive to lead. </B></div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">A decrease in the activity of this enzyme results</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> in an increase of the substrate, erythrocyte protoporphyrin (EP), </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">in the red blood cells. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Recent data indicate that the EP level, which has been used to screen for lead toxicity in the past, is not sufficiently sensitive at lower levels of blood lead and is therefore not as useful a screening test for lead poisoning as previously thought. </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead inhibits several enzymes that are critical to the synthesis of heme.</B> </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead poisoning in children only rarely</B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">results in anemia</B>. </div> <bR> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead can induce two types of anemia.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> <B>Acute high-level lead poisoning has been associated with hemolytic anemia.</B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> In chronic lead poisoning, lead induces anemia by both interfering with erythropoiesis and by diminishing red blood cell survival.</B></div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> It should be emphasized, however, that anemia is not an early manifestation of lead poisoning and is evident only when the blood lead level is significantly elevated for prolonged periods. </div> <bR> <bR> <div> <B>Endocrine Effects </B></div> <bR> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead interferes with a hormonal form of vitamin D, which affects multiple processes</B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">in the body, including cell maturation and skeletal growth.</B> </div> <bR> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">A strong inverse correlation exists between blood lead levels and levels of vitamin D. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Because the vitamin D-endocrine system is responsible in large part for the maintenance of extra- and intra-cellular calcium homeostasis, </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">it is likely that lead impairs cell growth and maturation and tooth and bone development. </div> <bR> <bR> <bR> <div> <B>Renal Effects </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead-induced chronic renal insufficiency may result in gout. </B></div> <bR> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">A direct effect on the kidney of long-term lead exposure is nephropathy. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Impairment of proximal tubular function manifests in </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">aminoaciduria, </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">glycosuria, </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">and hyperphosphaturia (a Fanconi-like syndrome). </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">There is also evidence of an association between lead exposure and hypertension, an effect that may be mediated through renal mechanisms. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Gout may develop as a result of lead- induced hyperuricemia, with selective decreases in the fractional excretion of uric acid before a decline in creatinine clearance. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Renal failure accounts for 10% of deaths in patients with gout. </div> <bR> <bR> <div> <B>Reproductive and Developmental Effects </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Maternal lead stores readily cross the placenta, placing the fetus at risk.</B> </div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">An increased frequency of miscarriages and stillbirths among women working in the lead trades was reported as early as the turn of the century. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Although the data concerning exposure levels are incomplete, these effects were probably a result of far greater exposures than are currently found in lead industries. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Reliable dose-effect data for reproductive effects in women are still lacking today. </div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Increasing evidence indicates that lead not only affects the viability of the fetus, but development as well.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Developmental consequences of prenatal exposure to low levels of lead include reduced birth weight and premature birth.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Lead is an animal teratogen; however, most studies in humans have failed to show a relationship between lead levels and congenital malformations. </div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The effects of lead on the male reproductive system in humans have not been well characterized.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> The available data support a tentative conclusion that testicular effects, including reduced sperm counts and motility, may result from chronic exposure to lead. </div> <bR> <bR> <div> <B>Carcinogenic Effects </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">EPA's Science Advisory Board has recommended</B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">that lead be considered a probable human carcinogen.</B> </div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Case reports have implicated lead as a potential renal carcinogen in humans, but the association remains uncertain. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Soluble salts, such as lead acetate and lead phosphate, have been reported to cause kidney tumors in rats.</div> <bR> <div> <B><U>Clinical Evaluation</U></B></div> <bR> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The first signs of lead poisoning in children are often subtle neurobehavioral problems that adversely affect classroom behavior and social interaction.</B> </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Speech or hearing impairments, or both, are not uncommon ln lead-exposed children.</B> </div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The physical examination should include special attention to the </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">hematologic, </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">cardiovascular, </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">gastrointestinal, </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">and renal systems. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The nervous system, including behavioral changes, should be carefully evaluated. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">A purplish line on the gums (lead line) is rarely seen today, but if present, usually indicates severe and prolonged lead poisoning. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">For children, hearing, speech, and other developmental milestones should be carefully evaluated and documented. In certain geographic areas, iron deficiency is common in children 9 to 24 months of age.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Since iron and calcium deficiencies are known to enhance the absorption of lead and to aggravate pica, it is especially important to assess the nutritional status of young children. </div> <bR> <bR> <div> <B>Signs and Symptoms </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Most persons with lead toxicity are not overtly symptomatic.</B> </div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Because of differences in individual susceptibility, symptoms of lead intoxication and their onset may vary. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">With increasing exposure, the severity of symptoms can be expected to increase. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Those symptoms most often associated with varying degrees of lead toxicity are listed below. In symptomatic lead intoxication, blood lead levels generally range from 35 to 50 mcg/dL in children and 40 to 60 mcg/dL in adults. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Severe toxicity is frequently found in association with blood lead levels of 70 mcg/dL or more in children and 100 mcg/dL or more in adults. </div> <bR> <bR> <div> <B>Continuum of signs and symptoms associated with lead toxicity</B> </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Mild Toxicity</B> </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Myalgia or paresthesia </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Mild fatigue </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Irritability </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lethargy </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Occasional abdominal discomfort</div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Moderate Toxicity</B> </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Arthralgia </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">General fatigue </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Difficulty concentratingI>Muscular exhaustibility </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Tremor </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Headache </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Diffuse abdominal pain </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Vomiting </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Weight loss </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Constipation</div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Severe Toxicity</B> </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Paresis or paralysis </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Encephalopathy-may abruptly lead to seizures, changes in consciousness, coma, and death </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead line (blue-black) on gingival tissue </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Colic (intermittent, severe abdominal cramps) </div> <bR> <div> <B><U>lead encephalopathy</U></B></div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> In the acute presentation, there may be</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> persistent vomiting, </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">seizures,</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">ataxia, </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">altered mental status, </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">papilledema and coma. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">A spinal tap (carefully performed after CT) might reveal </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">pleocytosis,</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> mild elevated protein </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">and increased opening pressure.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Lead encephalopathy rarely occurs at blood lead levels below 100 µg/dL. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">However, children with elevated blood lead levels, even well below 100 µg/dL, may present with a constellation of neurologic symptoms</div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Some of the hematologic signs of lead poisoning mimic other diseases or conditions. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">In the differential diagnosis of microcytic anemia, lead poisoning can usually be ruled out by obtaining a venous blood lead concentration; </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">if the blood lead level is less than 25 mcg/dL, the anemia usually reflects iron deficiency or hemoglobinopathy.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Two rare diseases, acute intermittent porphyria and coproporphyria, also result in heme abnormalities similar to those of lead poisoning. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Other effects of lead poisoning can be misleading.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Patients exhibiting neurologic signs due to lead poisoning have been treated only for peripheral neuropathy or carpal tunnel syndrome, delaying treatment for lead intoxication.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Failure to correctly diagnose lead induced gastrointestinal distress has led to inappropriate abdominal surgery</div> <bR> <div> <B>Laboratory Evaluation</B></div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">If pica or accidental ingestion of lead-containing objects (such as curtain weights or fishing sinkers) is suspected, an abdominal radiograph should be taken. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Hair analysis is not usually an appropriate assay for lead toxicity because no correlation has been found between the amount of lead in the hair and the exposure level. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The probability of environmental lead contamination of a laboratory specimen and inconsistent sample preparation make the results of hair analysis difficult to interpret. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Suggested laboratory tests to evaluate lead intoxication include the following: </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">CBC with peripheral smear </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Blood lead level </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Erythrocyte protoporphyrin level </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">BUN and creatinine level </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Urinalysis </div> <bR> <div> <B>CBC with Peripheral Smear.</B></div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> In a lead-poisoned patient, the hematocrit and hemoglobin values may be slightly to moderately low. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The differential and total white count may appear normal. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The peripheral smear may be either normochromic and normocytic or hypochromic and microcytic.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Basophilic stippling is usually seen only in patients who have been significantly poisoned for a prolonged period.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Eosinophilia may appear in patients with lead toxicity but does not show a clear dose-response effect. </div> <bR> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Basophilic stippling is not always seen in leadpoisoned patients.</B> </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The best screening and diagnostic test for lead poisoning is a blood lead level.</B> </div> <bR> <bR> <div> <B>Blood Lead Level. </B></div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">A blood lead level is the most useful screening and diagnostic test for lead exposure. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">A blood lead level reflects lead's dynamic equilibrium between absorption, excretion, and deposition in soft- and hard-tissue compartments.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> For chronic exposures, blood lead levels often underrepresent the total body burden; nevertheless, </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">it is the most widely accepted and commonly used measure of lead exposure. Blood lead levels respond relatively rapidly to abrupt or intermittent changes in lead intake (for example, ingestion of lead paint chips by children) and, within a limited range, bear a linear relationship to those intake levels. </div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead is most harmful to children under 6 years of age.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Every child who has a developmental delay, behavioral disorder, or speech impairment, or who may have been lead-exposed, should be considered for a blood lead test.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Equally important, siblings, housemates, and playmates of children with suspected lead toxicity probably have similar exposures to lead and should be promptly screened. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">For occupationally exposed adults, consult the federal lead standard for the mandated type and frequency of lead screening (see Workplace, Air). </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Today, the average blood lead level in the U.S. population is below 10 mcg/dL, down from an average of 16 mcg/dL (in the 1970s), the level before the legislated removal of lead from gasoline. </B></div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">A blood lead level of 10 mcg/dL is about 3 times higher than the average level found in some remote populations. </div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The levels defining lead poisoning have been progressively declining. (See Biologic Guidelines in Standards and Regulations.) Currently, the consensus level of concern for children is 10 to 14 mcg/dL . </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Effects on stature have been reported to begin at levels as low as 4 mcg/dL, the present limit for accurate blood lead measurement. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Taken together, effects occur over a wide range of blood lead concentrations, with no indication of a threshold. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">No safe level has yet been found for children. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Even in adults, effects are being discovered at lower and lower levels as more sensitive analyses and measures are developed. </div> <div> <B>EP and ZPP </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Using an EP or ZPP assay to screen children for lead poisoning is not as useful as once thought.</B> </div> <bR> <div> Treatment and Management</div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">All therapeutic chelating agents have potentially adverse side effects and should be used cautiously.</B> </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The type of therapy required will normally depend on the patient's blood lead level. </B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Asymptomatic patients with blood lead levels below 25 mcg/dL</B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">usually require only separation from the source of exposure.</B> </div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Children with blood lead levels of 45 mcg/dL or greater should be referred for appropriatechelation therapy immediately.</B> </div> <bR> <div> <TABLE BORDER="2" CELLPADDING="1" CELLSPACING="1" WIDTH="632" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=CENTER HEIGHT= 94 ><NOBR><div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The EDTA challenge test will indicaate the extent</B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">of lead stores in the body. Some practitioners use this test</B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">when deciding whether to institute chelation therapy</B></div> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">for a patient with a blood level between 25 and 44 mcg/dL.</B> </div> <div>  <A NAME="table_2"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="1" ALIGN="bottom" WIDTH="1" HSPACE="0" VSPACE="0" ></A></div> </NOBR></tD> </tR> </TABLE></div> <div> Blood Lead Level (µg/dL)</div> <div> <TABLE BORDER="2" CELLPADDING="1" CELLSPACING="1" WIDTH="442" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=CENTER HEIGHT= 44 WIDTH="166"><div> Blood Lead Level (µg/dL)</div> </tD> <tD VALIGN=CENTER WIDTH="261"><div> Recommendation(s)</div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 19 WIDTH="166"><div> 0-9</div> </tD> <tD VALIGN=CENTER WIDTH="261"><div> No treatment</div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 19 WIDTH="166"><div> 10</div> </tD> <tD VALIGN=CENTER WIDTH="261"><div> "Lead poisoning"</div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 19 WIDTH="166"><div> 10-14</div> </tD> <tD VALIGN=CENTER WIDTH="261"><div> Environmental analysis</div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 19 WIDTH="166"><div> 15-19</div> </tD> <tD VALIGN=CENTER><NOBR><div> Environmental analysis, education</div> </NOBR></tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 38 WIDTH="166"><div> 20-24</div> </tD> <tD VALIGN=CENTER WIDTH="261"><div> Remove from source, bring to medical attention</div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 38 WIDTH="166"><div> 25-54</div> </tD> <tD VALIGN=CENTER WIDTH="261"><div> Remove from source, do EDTA test (see below)</div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 38 WIDTH="166"><div> 55-69</div> </tD> <tD VALIGN=CENTER WIDTH="261"><div> Remove from source EDTA or DMSA (see below)</div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 57 ><NOBR><div> 70 or symptomatic</div> </NOBR></tD> <tD VALIGN=CENTER WIDTH="261"><div> Emergency hospitalization BAL and EDTA (see below)</div> <div> Return the child to a clean house</div> </tD> </tR> </TABLE></div> <div> EDTA = edetate calcium disodium</div> <div> DMSA = succimer (dimercaptosuccinic acid)</div> <div> BAL = dimercaprol</div> <bR> <div> Chelation is the key </div> <bR> <div> And what about asymptomatic children with serum lead levels between 45-69?</div> <bR> <div> <FONT SIZE="3" COLOR="#008000" FACE="Arial" >Answer</FONT>: Asymptomtic children at this level almost always should be treated. The treatment may consist of EDTA alone - 1,000 mg/m<FONT SIZE="1" COLOR="#000000" FACE="Arial" >2</FONT> /24 hour intravenously, in a 24-hr infusion or in a short (20 to 30 min infusion) for 5 consecutive days. EDTA is best given intravenously. When the intravenous route is not possible, EDTA may be given intramuscularly. Unfortuantely, IM EDTA is extremely painful, and the pain is only partially relieved if the drug is mixed with procaine. EDTA can be administered again, if needed, after a 2-day interval.</div> <div> An alternative therapy consists of Succimer, also known as DMSA (Chemet). DMSA can be given orally, has minimal side effects, and appears to be an excellent chelator. However, do not use outpatient DMSA unless you are certain that the child's environment is perfectly clean. Give DMSA for 5 days at a dose of 350 mg/m<FONT SIZE="1" COLOR="#000000" FACE="Arial" >2</FONT> every 8 hours for 5 consecutive days, followed by 2 weeks more of therapy at reduced frequency (350 mg/m<FONT SIZE="1" COLOR="#000000" FACE="Arial" >2</FONT> every 12 hr) for a total of 19 days. Additional courses may be given, if necessary, after a 2-week interval. Repeated courses of treatment may be necessary in these children to bring the blood lead into a safe range (<20 µg/dL). </div> <div>  <A NAME="dont"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="1" ALIGN="bottom" WIDTH="1" HSPACE="0" VSPACE="0" ></A><FONT SIZE="4" COLOR="#000000" FACE="Arial" >Don't seize this.... </FONT></div> <bR> <div> What is the treatment for those children who are symptomatic or with levels >70?</div> <bR> <div> <FONT SIZE="3" COLOR="#008000" FACE="Arial" >Answer</FONT>: In symptomatic children, regardless of blood lead level, begin treatment in the hospital setting. Children with blood lead levels of 70 µg/dL or more, even if asymptomatic, should also be considered medical emergencies and immediately hospitalized. Give dimercaprol (BAL 75 mg/m<FONT SIZE="1" COLOR="#000000" FACE="Arial" >2</FONT> every 4 hours; total daily dose of 450 mg/m<FONT SIZE="1" COLOR="#000000" FACE="Arial" >2</FONT>), followed by edetate calcium disodium (EDTA 1,500 mg/m<FONT SIZE="1" COLOR="#000000" FACE="Arial" >2</FONT> /24 hour by continuous infusion).</div> <div> Be sure to start with BAL and then initiate the EDTA only 3-4 hours later. EDTA, by binding zinc, will also cause a burst of delta-aminolevulinic acid (a neuro toxin - see question 8.3 2) that can cause seizures. Continue treatment for 5 days, suspending BAL as soon as the blood lead level falls below 60 µg/dL. Repeated courses of treatment may be necessary in these children until the blood lead level returns to a safe range (<20 µg/dL). </div> <div>  <A NAME="dust"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="1" ALIGN="bottom" WIDTH="1" HSPACE="0" VSPACE="0" ></A><FONT SIZE="4" COLOR="#000000" FACE="Arial" >Dust busters </FONT></div> <bR> <div> Before Mrs. Plumbody leaves to take Pika for the EDTA test, what do you tell her will be necessary for her family's environmental safety?</div> <bR> <div> Answer<FONT SIZE="3" COLOR="#000000" FACE="Arial" >: Tell Mrs. Plumbody that the most important aspect of therapy is to remove the child from the source of exposure to lead. It will be necessary for the Health Department to analyze the child's house and environment. Removal of the child from the source of contamination must be complete and keep in mind there may be more than one source (babysitter, grandmother's house, etc). Remove the child to a safer home that has been inspected by the Health Department.</FONT></div> <div> While the child's home is being repaired, the child should stay away from it at all times. Repairs, you tell Mrs. Plumbody, should be followed by cleaning with a high-efficiency particle accumulator (HEPA) vacuum cleaner, then the areas washed and scrubbed thoroughly with a high-phosphate detergent several times and vacuumed again. </div> <div> Pika smiles at you as you are about to leave the room. She hands you her Dixie cup and asks you if you can get her "some more ice to eat</div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Specific antidotes for lead poisoning should be administered for both acute and chronic lead poisoning. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">These are called chelating agents which bind circulating lead in the blood. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">These drugs include Calcium EDTA (given by injection), d-penicillamine (given orally) and more recently, Succimer (DSMA), also given orally. </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Because these chlating agents, possibly with the exception of Succimer, only bind circulating lead in the blood, repeat courses may be required because lead is released slowly from soft tissues such as the brain back into the systemic circulation</div> <div> <B>Treatment of Lead Toxicity</B></div> <div> <B>Environmental Changes.</B> Avoidance of further lead exposure is the primary mode of treatment.</div> <div> <B>Dietary Modifications</B>. Patients with iron deficiency have increased absorption of lead; therefore, iron deficiency should be treated. Adequate calcium, zinc, and protein may also reduce lead absorption.</div> <div> <B>Chelation Therapy</B> </div> <div> Treatment of acute poisoning consists of one or more chelating agents.</div> <bR> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">EDTA </B></div> <div> This agent binds to lead and is excreted in urine. The usual daily dose is 1,000 mg/m<FONT SIZE="1" COLOR="#000000" FACE="Arial" >2</FONT> for 5 days, preferably administered intravenously. If the agent is given IM, procaine hydrochloride (Novocain) is added for pain control. </div> <div> The dose may be repeated every 2 to 5 days as needed. Renal tubular necrosis and reversible hepatocellular disease may occur. Adequate hydration and frequent monitoring of urinalyses is necessary.</div> <bR> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Succimer (</B> <B>Chemet)</B> is the only oral agent approved for chelation of lead. Efficacy is comparable to EDTA.</div> <div> Succimer is given in doses of 10 mg/kg tid for 5 days and then bid for an additional 2 weeks. The adult dose is 500 mg tid for 5 doses, followed by 500 mg bid for 14 days. Repeated courses may be given, with a minimum of 2 weeks between courses. The 100 mg capsules can be mixed with food or fruit drinks.</div> <div> Succimer has a "rotten egg" sulfur odor. Common side effects include abdominal pain, nausea, vomiting, diarrhea, and elevation of liver enzyme levels.</div> <bR> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Dimercaprol</B> binds with lead and is excreted in urine and bile. Unlike EDTA, it chelates lead from the brain. Dimercaprol is commonly combined with EDTA to treat lead encephalopathy; urine is alkalinized during treatment.</div> <bR> <div> <B><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Penicillamine</B> ( Cuprimine, Depen) may be given for treatment of lead poisoning, but it is not FDA approved. </div> <div> <TABLE BORDER="2" CELLPADDING="1" CELLSPACING="1" WIDTH="884" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=CENTER COLSPAN=2 BGCOLOR=#000000 HEIGHT= 20 WIDTH="872"><div> <B>Management of Lead Toxicity</B></div> </tD> </tR> <tR> <tD VALIGN=CENTER BGCOLOR=#FFFFFF HEIGHT= 39 WIDTH="130"><div> <B>Blood Lead Level (</B><FONT SIZE="1" COLOR="#000000" FACE="WP MathA" ><B>F</B></FONT><B>g/dL)</B></div> </tD> <tD VALIGN=CENTER WIDTH="739"><div> <B>Action</B></div> </tD> </tR> <tR> <tD VALIGN=CENTER BGCOLOR=#FFFFFF HEIGHT= 19 WIDTH="130"><div> <30 </div> </tD> <tD VALIGN=CENTER WIDTH="739"><div> Monitor history and retest as indicated.</div> </tD> </tR> <tR> <tD VALIGN=CENTER BGCOLOR=#FFFFFF HEIGHT= 35 WIDTH="130"><div> 30 to 40</div> </tD> <tD VALIGN=CENTER WIDTH="739"><div> Monitor blood lead levels every 6 mo. All patients with levels >30 <FONT SIZE="1" COLOR="#000000" FACE="WP MathA" >F</FONT><FONT SIZE="1" COLOR="#000000" FACE="Arial" >g/dL should receive a history, physical examination, screening test for iron deficiency, and environmental modification. If iron deficiency is present, iron supplementation is provided.</FONT></div> </tD> </tR> <tR> <tD VALIGN=CENTER BGCOLOR=#FFFFFF HEIGHT= 35 WIDTH="130"><div> 41 to 50</div> </tD> <tD VALIGN=CENTER WIDTH="739"><div> Retest blood lead level every 2 mo until two consecutive results are <40 <FONT SIZE="1" COLOR="#000000" FACE="WP MathA" >F</FONT><FONT SIZE="1" COLOR="#000000" FACE="Arial" >g/dL. If the patient is symptomatic, remove from lead exposure.</FONT></div> </tD> </tR> <tR> <tD VALIGN=CENTER BGCOLOR=#FFFFFF HEIGHT= 35 WIDTH="130"><div> >50 </div> </tD> <tD VALIGN=CENTER WIDTH="739"><div> <FONT SIZE="3" COLOR="#000000" FACE="Arial" >Remove patient from lead exposure until blood level is </FONT>#<FONT SIZE="1" COLOR="#000000" FACE="Arial" >40 </FONT>F<FONT SIZE="1" COLOR="#000000" FACE="Arial" >g/dL. Consider treatment with EDTA or succimer (Chemet) if the patient is symptomatic. Retest at least every 2 mo.</FONT></div> </tD> </tR> <tR> <tD VALIGN=CENTER BGCOLOR=#FFFFFF HEIGHT= 19 WIDTH="130"><div> >80</div> </tD> <tD VALIGN=CENTER><NOBR><div> Consider treatment with EDTA or succimer. If encephalopathy is present, dimercaprol and EDTA are given.</div> </NOBR></tD> </tR> </TABLE></div> <div> <B>Follow-up Care</B></div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Chelation therapy is discontinued when lead levels are less than 25 <FONT SIZE="1" COLOR="#000000" FACE="WP MathA" >F</FONT><FONT SIZE="1" COLOR="#000000" FACE="Arial" >g/dL. </FONT></div> <div> <IMG BORDER="0" SRC="Symb075c00b700b400000000.png" HEIGHT="12" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Therapy should be repeated if the level rebounds to within 5 <FONT SIZE="1" COLOR="#000000" FACE="WP MathA" >F</FONT><FONT SIZE="3" COLOR="#000000" FACE="Arial" >g/dL of the pretreatment value.</FONT> </div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Children with blood lead levels between 10-24 <FONT SIZE="1" COLOR="#000000" FACE="WP MathA" >F</FONT><FONT SIZE="1" COLOR="#000000" FACE="Arial" >g/dL </FONT></div> <div> <IMG BORDER="0" SRC="Symb075c00b700b400000000.png" HEIGHT="12" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">after treatment should continue environmental modification and have periodic blood level monitoring. When pretreatment levels are higher than 45 <FONT SIZE="1" COLOR="#000000" FACE="WP MathA" >F</FONT>g/dL in children and 80 <FONT SIZE="1" COLOR="#000000" FACE="WP MathA" >F</FONT><FONT SIZE="3" COLOR="#000000" FACE="Arial" >g/dL in adults, blood lead levels should be measured immediately after treatment.</FONT></div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0"> Lead levels should be rechecked in all patients within 7-21 days.</div> <div> <FONT SIZE="3" COLOR="#000000" FACE="Arial" ><IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">After chelation therapy, close monitoring is warranted for at least 1 year or until blood lead levels have dropped below 25 </FONT>F<FONT SIZE="1" COLOR="#000000" FACE="Arial" >g/dL in children and 40 </FONT>F<FONT SIZE="3" COLOR="#000000" FACE="Arial" >g/dL in adults.</FONT></div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Children are monitored for developmental and hearing problems.</div> <div> <B>Prevention</B></div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Lead-based paint should be covered or removed. If the water system contains lead solder or pipes, only cold water should be used for cooking and drinking; the cold water tap should be allowed to run for several minutes before water is used.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Pottery that is used for food should be lead-free.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700f000000000.png" HEIGHT="16" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Children should play only in areas that are located away from heavy traffic and away from lead contaminated buildings</div> <bR> <bR> <bR> <bR> <bR> <bR> <bR> <DIV ALIGN="LEFT"></DIV> <div>    <SCRIPT>  </SCRIPT>  <form method="POST" action="http://mindit.netmind.com/mindit.shtml" target="_top"> <input type="hidden" name="SOURCE" value="511"> <input type="hidden" name="URL" value="^SITEURLTlxTransfer.txt"> <input type="hidden" name="DOC_TITLE" value="^SITENAME"> <input type="hidden" name="REDIRECT" value="^SITEURL"> <table border="0" cellpadding="5" cellspacing="0"><tr><td align="center"> <font face="arial,helvetica" size="-1"><b>Click to receive email <br>when this web site is updated</b></font></td> </tr><tr><td align="center"> <input type="image" src="http://mindit.netmind.com/images/mindit511.gif" border="0"></td> </tr><tr><td align="center"> <font face="arial,helvetica" size="-2">•<b> Powered by <a href="http://www.netmind.com" target="_top">NetMind</a> </b>•</font> </td></tr></table></form>   </div> <div> <A HREF="http://www.trellix.com" TARGET="_top" TITLE="http://www.trellix.com"><U><IMG SRC="04652280.png" border=0 width="82" height="40" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></U></A></div> </td> </tr></table></body>