Neurologic disorders occurring in children following lead exposure. The most frequent manifestation of childhood lead toxicity is an encephalopathy associated with chronic ingestion of lead that usually presents between the ages of 1 and 3 years. Clinical manifestations include behavioral changes followed by lethargy; CONVULSIONS; HALLUCINATIONS; DELIRIUM; ATAXIA; and vomiting. Elevated intracranial pressure (HYPERTENSION, INTRACRANIAL) and CEREBRAL EDEMA may occur. (From Adams et al., Principles of Neurology, 6th ed, p1210-2).