Child neurology: diagnosis of Lambert-Eaton myasthenic syndrome in children.

OBJECTIVE To report a case of Lambert-Eaton myasthenic syndrome (LEMS) in a child and review the existing literature of LEMS in children. METHODS We report a pediatric case of LEMS with the classic clinical triad of proximal weakness, autonomic dysfunction, and areflexia; the characteristic increment in compound motor action potential on high-frequency repetitive nerve stimulation; and positive serum P/Q-type voltage-gated calcium channel antibodies. Only 11 pediatric cases of LEMS have been reported in the literature. RESULTS The patient's presentation with LEMS led to the diagnosis of occult neuroblastoma. Based on review of the existing pediatric literature, no consistent clinical or electrodiagnostic criteria exist to diagnose LEMS in children. CONCLUSIONS There exists a need for consistent clinical criteria and electrodiagnostic testing for prompt diagnosis of LEMS in children. Prompt identification of LEMS will alert the physician to search for malignancy or another immune-mediated process.