History suggests delayed language ability, slightly impaired hearing, short stature, possible attention deficit disorder, and anemia. The child is also experiencing passive exposure to his mother’s cigarette smoke and family disruption related to his parents’ divorce.
Three of the most common causes of microcytic anemia are iron deficiency, hemoglobinopathy, and lead poisoning. In lead-poisoned patients, anemia is usually evident only when the blood lead level is significantly elevated for prolonged periods. It manifests in only a relatively small number of children with chronic lead poisoning. It is possible for a patient to be both lead-poisoned and to have anemia due to some other cause. The relative rarity of nutritional iron deficiency in this boy’s age group and the absence of evidence for blood loss suggest consideration of other etiologies to explain the anemia.
An elevated ZPP level is most often due to iron deficiency anemia, hemolytic anemias, or lead poisoning. A rare disease that may cause the ZPP level to be markedly elevated is erythropoietic protoporphyria.
To confirm lead poisoning, the best test is a venous blood lead level. If the blood lead level is below 25 µg/dl, then a serum ferritin level and other iron studies can be used to determine if iron deficiency anemia exists.
With an elevated blood lead level of 50 µg/dL, the conclusion is that the boy is lead-poisoned. In this case, the child should be referred for appropriate chelation therapy immediately. It is important to immediately identify and eliminate all sources of lead exposure for both the boy and his family. Environmental evaluation, intervention, and remediation should begin immediately. All household members should be screened for lead exposure (See Table 1, page 15). Adequate diet for the family should be stressed.
You should consult with a physician experienced in treating lead-poisoned patients. To identify such physicians, contact your state or local health department, a university medical center, or a certified regional poison control center.
Knowing the subgroups at greatest risk of lead exposure, you should take every opportunity to educate these subpopulations, your colleagues, and the community about the hazards of lead poisoning and the steps to prevent its occurrence. Those children and members of the community whom you suspect may be in danger of lead poisoning should be promptly screened.
In certain states, public health authorities must be notified if a patient’s blood lead level and ZPP level exceed certain limits. In any case, you should contact your state or local health department so all sources of lead in the home can be identified and abated. You should also notify OSHA so the radiator repair shop can be brought, if required, into compliance with the federal lead standard. A NIOSH health hazard evaluation could also be requested. The reason for notifying these agencies is to prevent lead exposure in others.
The federal lead standard mandates that a worker with a blood lead level of 60 µg/dl or higher (or an average of 50 µg/dL)undergo medical removal from the lead hazard and be reassigned with retention of job seniority and pay. In addition to referring her for obstetrical evaluation, you should recommend that the mother talk to her employer, employee representative, and OSHA to clarify her work status under the lead standard and possible reinstatement procedures.
More information on the adverse effects of lead and the treatment and management of lead-exposed persons can be obtained from ATSDR, your state and local health departments, and university medical centers. Case Studies in Environmental Medicine: Lead Toxicity is one of a series. For other publications in this series, please use the order form on the back cover. For clinical inquiries, contact ATSDR, Division of Health Education, Office of the Director, at (404) 639–6204.