Diagnostic efficacy of cutaneous nerve biopsy in primary neuritic leprosy.

The role of nerve biopsy in the diagnosis of primary neuritic leprosy was evaluated in a study of 77 patients who had symptoms of peripheral neuropathy without hypopigmented patches, positive skin smears, or a skin biopsy consistent with leprosy. A biopsy of a representative cutaneous nerve near the site of the neurological deficit was taken for histopathological examination and acid-fast staining. Nearly half of the patients had leprosy confirmed by nerve biopsy, and the entire spectrum of leprosy was represented. No significant relationship was seen by age or sex or type of neuropathy. The duration of symptoms did not correlate with the severity of nerve damage as seen histologically. The probability of false-positive or false-negative results is discussed in light of clinical management. Being a relatively simple office procedure, a cutaneous nerve biopsy is strongly recommended as an important diagnostic tool, particularly for primary neuritic leprosy.