Leprous neuropathy: a clinical and neurophysiological study

Leprosy is one of the most common treatable causes of neuropathy in the world. Peripheral nerves and skin are commonly affected. We reported the clinical features and electrophysiological findings in 46 patients with leprosy. The aim of our study was to evaluate the nature of damage in the nerve fibres, especially in the first phase of disease. Forty‐six patients (mean age: 44.8 ± 17.8) with diagnosed leprosy were studied by neurological examination and nerve conduction studies (NCS). Twenty‐eight patients were examined for a mean period of 34.8 months. The number of tests for patients varied from 1 to 13 controls. Amplitude of sensory and motor action potentials (SNAP and MAP), sensory‐motor conduction velocity of median, ulnar, tibialis, peroneal and sural nerves were evaluated. Abnormalities were found in 282 of 647 nerves investigated (37.56%), sensory nerve abnormalities being more frequent than motor (50.16% 29.45). Of 282 nerves with neurophysiological abnormalities, 123 were clinically asymptomatic (43.62%). A statistically significant correlation between duration of disease and number of electrophysiological abnormalities was demonstrated. In 19 nerves partial "conduction‐block"(reduction of cMAP > 50% in the proximal response) was individuated. The first electrophysiological alteration, suggesting segmental demyelination, was detected in 41 nerves of 21 patients (33.3 %). According to this view, our data support the hypothesis that leprosy induces a neuropathy of demyelinating nature in the first phase.