RESUMO
BACKGROUND: Nerve involvement developed in a patient with granuloma annulare, as evidenced by a perineural infiltrate of histiocytes in the dermis. The histopathologic pattern was suggestive of leprosy. No mycobacteria were observed, and neurologic testing was normal. OBJECTIVE: To determine whether inflammation of the nerves or perineural tissue is common in granuloma annulare, we studied the cutaneous nerves in skin biopsy specimens from 14 patients with granuloma annulare. METHODS: Sections were stained with hematoxylin-eosin to highlight inflammatory cells and with S-100 to identify cutaneous nerves. RESULTS: No inflammation around nerves was found in 12 specimens, abutting granulomatous inflammation was found in 1 specimen, and enveloping granulomatous inflammation was found in 1 specimen. No nerves were infiltrated by inflammatory cells. CONCLUSION: Perineural granulomatous inflammation resembling the perineural infiltrate of leprosy appears to be an uncommon characteristic of granuloma annulare. Clinical correlation and acid-fast stains can assist in establishing the correct diagnosis.