Electroneuromyographic sequelae of tetanus, a controlled study of 40 patients

To assess the peripheral nervous system involvement caused by tetanus 40 patients recovered from tetanus and their sex and age matched referents were submitted to electroneuromyography (ENMG). Clinical symptoms and signs of peripheral neuropathy were found in 6 patients, 3 of whom had other obvious aetiology than tetanus. EMG was examined of the masseters and three muscles in the extremities. Motor conduction velocities (MCVs) were examined of the median, ulnar and peroneal nerves, distal sensory conduction velocity (dSCV) of the median, ulnar and radial nerves and the sensory conduction velocity (SCV) of the median nerve. Repetitive stimulation was done to study the neuromuscular transmission. The patients had significantly longer motor distal latencies (DLs) and slower dSCVs and more frequent ENMG findings compatible with mono- or polyneuropathy than their referents. There was no systematical difference in the MCVs. These findings suggest that tetanus may cause toxic axonal polyneuropathy, sequels of which appear to be slight or subclinical and can be seen at a group level.