Cutaneous tuberculosis in the modern era: A case series of diverse clinical presentations

Abstract

Cutaneous tuberculosis (CTB) is a rare manifestation of extra-pulmonary tuberculosis characterized by diverse clinical presentations that often result in delayed diagnosis. This case series describes seven patients with CTB diagnosed at a tertiary care center, highlighting the clinical spectrum, histopathological findings, diagnostic utility of Cartridge-Based Nucleic Acid Amplification Test (CBNAAT), and treatment outcomes. Among the seven cases, four (57.1%) were diagnosed as scrofuloderma and three (42.9%) as tuberculosis verrucosa cutis (TBVC). Scrofuloderma predominantly involved the cervical region and presented as nodules progressing to ulcers with violaceous undermined margins, while TBVC manifested as chronic verrucous plaques over the foot and buttock. One patient was HIV-positive with associated pulmonary tuberculosis. Histopathological examination revealed epithelioid granulomas with Langhans giant cells in all cases, with pseudoepitheliomatous hyperplasia being a characteristic feature of TBVC. CBNAAT confirmed Mycobacterium tuberculosis infection in 85.7% of patients and significantly aided early diagnosis. All patients showed favorable clinical response following standard antitubercular therapy. This series underscores the continued relevance of CTB in tuberculosis-endemic regions and emphasizes the importance of maintaining a high index of suspicion, supported by histopathological examination and modern molecular diagnostics, for timely diagnosis and effective management.