Blink reflex, H-reflex and nerve-conduction alterations in leprosy patients.

Peripheral nerve lesions are the most important cause of disability in leprosy patients. Electrophysiological studies are used in the diagnosis and prognosis of neuropathy. Nerve conduction is the most frequently used electrophysiological test method to detect neuropathy, although it evaluates only a part of the peripheral nervous system. Blink reflex and H-reflex are electrophysiological tests which evaluate facial and trigeminal nerve function. This study determined the frequencies of blink reflex, H-reflex and motor and sensory nerve conduction alterations in twenty five heterogeneous, clinic patients with lepromatous leprosy and a control group of 20 healthy subjects. Study results showed a decrease in motor and sensory nerve conduction in 40% and 30%, respectively. In blink reflex (BR), right R1 was altered in latency in 20% of patients, left R1 in 20%, right ipsilateral R2 in 16%, left ipsilateral R2 in 20%, and right and left contralateral R2 were altered in 32% of patients. There was an absence of H-reflex in 16% (n = 4) and prolonged latency in 4% (n = 1).