lead poisoning /led/ , a toxic condition caused by the ingestion or inhalation of lead or lead compounds. Many children develop the condition as a result of eating flaked lead paint. Poisoning also occurs from the ingestion of water from lead pipes and lead salts in certain foods and wines, the use of pewter or earthenware glazed with a lead glaze, and the use of leaded gasoline. Inhalation of lead fumes is common in industry. The acute form of intoxication is characterized by a burning sensation in the mouth and esophagus, colic, constipation or diarrhea, mental disturbances, and paralysis of the extremities, followed in severe cases by convulsions and muscular collapse. Chronic lead poisoning, which is characterized by extreme irritability, anorexia, and anemia, may progress to the acute form. Encephalopathy must be anticipated in children with lead poisoning. ▪ OBSERVATIONS: Lead poisoning is frequently asymptomatic, with mild toxicity. Likely initial manifestations include loss of appetite, abdominal discomfort, constipation, fatigue, irritability, headache, insomnia, and myalgia. Toxicity leads to three major clinical syndromes: cerebral (hyperactivity, behavior problems, learning problems, neurological disability, and/or cognitive impairment); neuromuscular (peripheral neuritis, paresthesias, and poor coordination); and alimentary (anorexia, abdominal cramping, weight loss, intestinal spasm, and rigidity of abdominal wall). Lead exposure in pregnant women can delay fetal development. Diagnosis is made by measuring lead levels in the blood, which will be greater than 10 μg/dL. Blood studies will also reveal a mild anemia with basophilic stippling. Chronic exposure may lead to renal failure, liver damage, and encephalopathy with blindness, seizures, paralysis, coma, and death. Hearing loss and tooth decay are also associated with lead exposure. ▪ INTERVENTIONS: Treatment is dictated by serum lead levels. Children with levels between 10 and 19 μg/dL are treated conservatively with calcium, iron, zinc, and vitamin C supplements. They are placed on an elevated-protein–reduced fat diet to reduce lead absorption. For children with blood levels between 20 and 44 μg/dL, case management with environmental assessment is recommended, with aggressive control and removal of lead hazards. Case reports are made to the local health department for lead levels more than 20 μg/dL. All occupationally related cases in the United States should be reported to the federal Occupational Safety and Health Administration (OSHA). Chelation with succimer and edetate calcium disodium (EDTA) is used in cases with blood levels greater than 45 μg/dL or in refractory cases. ▪ PATIENT CARE CONSIDERATIONS: All health care providers play an important role in the prevention of and screening for lead poisoning. All children should be screened for lead levels starting at 6 months to 1 year of age. Families should be educated about the risks of exposure to lead and instructed in the detection, removal, or treatment of potential sources of lead in and around the home. When the child has elevated lead levels, the focus is on aggressive reduction of further lead exposure. Education in diet and supplement therapy and the importance of continuing the monitoring of blood levels is also necessary. Families of children undergoing chelation need instructional preparation for the procedure. EMLA (lidocaine/prilocaine) cream should be applied before chelation administration to reduce pain at the injection or infusion site. Seizure precautions should be instituted for children with high lead blood levels. Renal function should be assessed through urinalysis, and lead blood levels rechecked after chelation. If lead exposure is occupationally related, workers should be instructed in the importance and consistent use of proper safety equipment such as respirators.
