A Case of Ataxic Gait Disturbance Due to 1-Bromopropane Neurotoxicity

A 55-year-old man presented a slowly progressive sensory disorder, predominantly in both lower limbs, and gait disturbance. Neurological examinations revealed abnormal sensation and spasticity in both lower limbs, and a wide-based gait. Although examination revealed mild hyperchloremia and decreased motor conduction velocity in the peroneal nerve, head and whole spine MRI, and spinal fluid examination were normal. His job history revealed he had been engaged in metal cleaning work using 1-bromopropane (1-BP) for three years. His serum bromide concentration was increased to 175.6 mg/l (standard value: 5 or less), so we diagnosed him as having 1-BP neurotoxicity. The serum bromide concentration decreased after avoidance of exposure to 1-BP, but the gait disturbance remained. It was considered that we should obtain a detailed job history and measure the serum bromide concentration in patients with a sensory disorder in the extremities and gait disturbance of unknown origin.