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Updated: May 16, 2026
06:35
An Immunohistopathologic Study to Profile the Folate Receptor Beta Macrophage and Vascular Immune Microenvironment in Giant Cell Arteritis
Published on: February 8, 2019
Nerve involvement in granuloma annulare.
Michelle Longmire1, David J DiCaudo, Mark V Dahl
1Department of Dermatology, Mayo Clinic, Scottsdale, AZ 85259, USA.
Journal of Cutaneous Medicine and Surgery
|November 15, 2012
Summary
Perineural inflammation is uncommon in granuloma annulare, with most cases showing no nerve involvement. This finding helps differentiate granuloma annulare from leprosy, which has similar histopathologic features.
Area of Science:
- Dermatopathology
- Neuropathology
Background:
- Granuloma annulare can present with histopathologic features mimicking leprosy.
- Nerve involvement in granuloma annulare requires careful evaluation to distinguish from other conditions.
Observation:
- This study investigated cutaneous nerve involvement in 14 patients with granuloma annulare.
- Skin biopsy specimens were analyzed for inflammation around nerves and perineural tissues.
Findings:
- No perineural inflammation was observed in 12 out of 14 specimens.
- Two specimens showed abutting or enveloping granulomatous inflammation, but no nerve infiltration.
- Histiocyte infiltrate suggestive of leprosy was noted in one initial case, but no mycobacteria were found.
Implications:
- Perineural granulomatous inflammation is an uncommon feature of granuloma annulare.
- Distinguishing granuloma annulare from leprosy relies on clinical correlation and specific stains like acid-fast stains.
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