Consecutive Reversible Changes of Peripheral Nerve Conduction in Tetrodotoxification

ABSTRACT

Tetrodotoxin (TTX) cause neurologic dysfunction by blocking the voltage-gated sodium channels located in all of the peripheral nerves and muscles. We experienced two patients presenting with generalized motor weakness after ingestion of pufferfish. The nerve conduction study showed diffuse slowing of motor and sensory nerve conduction velocity, prolonged motor terminal latency and decreased sensory nerve action potentials without temporal dispersion or conduction block. Abnormal findings of nerve conduction study improved rapidly without any deterioration. Clinical symptoms and signs ameliorated in accordance with findings of nerve conduction study without any neurologic sequelae. These imply that tetrodotoxication is reversible and functional neurologic disorder. We suggest that nerve conduction studies can be available in serial monitoring of tetrodotoxication as an objective means.