Infectious granulomatous dermatitis: Clinicohistopathological study with some unusual clinical presentation

Abstract

Introduction: Granulomatous dermatitis has a varied differential diagnosis ranging from infectious etiology to immune mediated diseases. In tropical countries like India, infectious etiology forms an important cause of granulomatous dermatitis with tuberculosis (TB) and leprosy being the major contributing factors. The present study was carried out with the aim to determine the frequency of various etiological agents causing infectious granulomatous dermatitis in our hospital setup and to see clinicohistopathological correlation in these cases. Materials and Methods: This is a hospital based retrospective study conducted in the department of pathology over a period of 1 year. All the skin biopsy cases diagnosed as infectious granulomatous dermatitis were retrieved from the histopathology record section for analysis and were categorized based on the causative etiological agents. Special stains were applied wherever necessary in addition to routine hematoxylin and eosin stain. Results: A total of 40 cases of infectious granulomatous dermatitis were included in the present study. Most common diagnosis was leprosy (57.5%), followed by TB (30.0%), actinomycosis (5.0%), dermatophytosis (2.5%), histoplasmosis (2.5%), and cysticercosis (2.5%). Gender wise distribution showed male predominance with 57.5% of cases and age wise distribution showed a peak in the age group of 41–60 years (32.5%). Clinicohistopathological correlation was found in 87.50% of the cases. The unusual clinical presentations were seen in cases of cysticercosis, actinomycosis, and histoplasmosis. Conclusion: Histopathological examination of the skin biopsies is an important diagnostic tool providing definitive diagnosis as well as clinicohistopathological correlation in cases of infectious granulomatous dermatitis.