Diagnosis and treatment of lead poisoning in children and adults

Abstract

Diagnosis of lead intoxication must be based basically on signs and symptoms produced by the main affected target organs: brain, hemopoietic system, kidneys, and periphery nervous system. The critical organ is the brain, promoting signs and symptoms of encephalopathy more or less pronounced according to the dose and duration of exposure. Such a symptoms are: headache, memory loss, concentration and attention problems, humor changes, irritability, depression, insomnia, somnolence, stupor, convulsions and coma. Diagnosis can be confirmed by blood and urine lead measurement, or by dosage of any parameter of lead effect on hemoglobin formation, like delta aminulevulinic acid in blood or urine and blood erythrocyte protoporphirin. Treatment is performed using chelating agents. Considering costs and commercial availability Brazilian experience regarding chelating agents for lead intoxications is limited to the use of dimecaprol (BAL), calcium versenate (EDTACaNa2) and D-penicilamine. However, the most efficacious drugs are intravenous EDTACaNa2, and oral dimercapto succinic acid (DMSA). BAL can be used together with EDTACaNa2 in adults when encephalopathic signs are present, or in children using EDTACaNa2 even without CNS signs and symptoms because BAL can pass blood-brain barrier chelating lead in the brain and protecting children against lead mobilization from other tissues to the brain provoked by EDTACaNa2.