Background: Granulomatous dermatitis frequently presents a diagnostic challenge to dermatopathologists because an identical histologic picture is produced by several causes, and conversely, a single cause may produce varied histologic patterns.
Methods: A retrospective analysis of skin biopsies received over a period of 7 years was performed, and cases of non-infectious granulomatous dermatitis diagnosed on histopathological examination were retrieved.
Results: Out of a total of 586 cases of granulomatous dermatitis, 71 cases (12.11%) were categorized as non-infectious granulomatous dermatitis on the basis of clinicopathological findings. Further subcategorization was done based on morphology of granulomas as epithelioid granulomas; 15 cases of sarcoidosis, 21.1%, one case of Crohn's vulvitis, 1.4%, necrobiotic granulomas; 11 cases of granuloma annulare, 15.4%, two cases of rheumatoid nodule, 2.8%, 10 cases of foreign body granulomas, 14.0%; 32 cases of miscellaneous group, 45%.
Conclusions: Morphology alone is seldom specific and cannot be used as a diagnostic tool for identification of specific diseases. Adequate clinical data and work up in combination of pathological resources can help in elucidation of specific etiology of granulomatous dermatitis. Mohan H, Bal A, Dhami GP. Non-infectious granulomatous dermatitis: a clinicopathological study.