Infectious granulomatous dermatoses: Clinico-histopathological correlation in punch biopsy specimens

Introduction: Granulomatous dermatoses are group of disorders which are caused by varied etiological agents and includes heterogenous lesions but often share a common histological feature of granuloma formation. Leprosy and cutaneous tuberculosis occupies the major proportion of this category. Leprosy is the most common chronic infectious granulomatous dermatoses caused by mycobacterium leprae. Cutaneous tuberculosis has varied mode of presentation. Materials and Methods: The present study is a one year retrospective study carried out in the Department of Pathology. All the skin biopsies of leprosy cases received in histopathology section from September 2016 to August 2017 were reviewed from the archives of the department. Results: Of 168 skin biopsies, 104 cases were included and remaining 64 cases were excluded. Among 104 cases, 96 cases were leprosy and 8 cases were tuberculosis. It included 73 males and 31 females. Most commonly affected age group was 21-40 years. Majority of the patients were found to have hypopigmented patch. Many of cases were borderline tuberculoid (26 cases) followed by lepromatous leprosy (18 cases). Among the 8 cases of tuberculosis, 4 were lupus vulgaris, 2 were cases of granulomatous chelitis and one cases each of papulonecrotic tuberculid and tuberculosis verrucosa cutis. Conclusion: Diagnosis of leprosy cases should be an integrated approach and includes dermatological, histopathological and microbiological examination. Leprosy is the most common infectious granulomatous dermatitis encountered which was presented clinically with hypopigmented patch. It was found to more common in third and fourth decade of life. This is followed by cutaneous tuberculosis.