anemia that results from a defect in hemoglobin synthesis However, much of the anemia seen in children with excess BLL may be caused by concurrent iron deficiency A moderately sensitive laboratory measure of lead effect on hemesynthesis is the evaluation of erythrocyte protoporphyrin (EP), a heme precursor Moderately elevated EP levels are seen in iron deficiency, but levels above 250 to 300 mcg/dL are almost always the result of chronic lead poisoning There is no safe threshold for lead exposure and the 97.5% for BLLs among young U.S children is mcg/dL The most important treatment for lead poisoning is to remove the lead exposure from the child’s environment The asymptomatic child discovered to have a BLL in the to 44 mcg/dL range, warrants thorough environmental investigation for lead hazards, clinical and nutritional evaluation, prudent follow-up by primary healthcare provider, and case management to reduce lead exposure as expeditiously as possible All symptomatic children and those with BLL higher than 44 mcg/dL warrant urgent treatment as outlined next The remainder of this discussion is addressed primarily to the early recognition and treatment of plumbism, including acute lead encephalopathy Though now rare, this single manifestation of chronic childhood lead poisoning is highlighted because it represents a true medical emergency The recognition of mildly symptomatic patients with lead poisoning (or asymptomatic children with high lead levels, who are at great risk to soon become symptomatic) requires a high index of suspicion All children between and years of age are suspect if they have (i) persistent vomiting, listlessness or irritability, clumsiness, or loss of recently acquired developmental skills; (ii) afebrile convulsions; (iii) a strong tendency to pica, including a history of acute exploratory ingestions or aural or nasal foreign body; (iv) a deteriorating preWorld War II house or a parent with industrial exposures; (v) a family history of lead poisoning; (vi) iron-deficiency anemia; or (vii) evidence of child abuse or neglect Recent immigration is a risk factor The child between the ages of and years who comes to the ED with an acute encephalopathy and the above-cited risk factors presents the physician with a dilemma: lead intoxication requires urgent diagnosis, but confirmation with a BLL is usually not available on an immediate basis A constellation of historical features increases the likelihood of lead poisoning These features include (i) a prodromal illness of several days’ to weeks’ duration (suggestive of mild symptomatic plumbism); (ii) a history of pica; and (iii) a source of exposure to lead Several nonspecific laboratory findings make lead poisoning likely enough to warrant presumptive chelation therapy until confirmation by lead levels is