Asian Journal of Research in Dermatological Science

Aims: We report a rare case of extensive tuberculosis verrucosa cutis (TBVC) with a sporotrichoid pattern, highlighting its dermoscopic features and diagnostic challenges. This case aims to raise awareness of atypical TBVC presentations and the potential value of dermoscopy in aiding diagnosis.

Presentation of Case: An 89-year-old immunocompetent woman presented with an eight-month history of asymptomatic verrucous plaques and nodules on the lower limbs in a sporotrichoid pattern, associated with an exudative lesion on the left ear. Dermoscopy revealed papillated surfaces, linear vessels, brown and red-orange structureless areas, chrysalides, and whitish scales. Histopathology showed granulomatous inflammation with caseous necrosis. Tuberculin skin test and interferon-gamma release assay were positive. Chest CT revealed cavitary pulmonary tuberculosis. A diagnosis of multifocal TBVC was made. The patient was treated with a six-month course of rifampicin, isoniazid, pyrazinamide, and ethambutol, leading to complete resolution of skin lesions.

Discussion: TBVC is a rare form of cutaneous tuberculosis, typically presenting as a solitary lesion. Sporotrichoid and multifocal patterns are exceptional. Dermoscopy may assist in differentiating TBVC from other infectious or inflammatory dermatoses. Diagnosis remains challenging due to negative microbiological results in most cases, making clinico-pathological correlation essential.

Conclusion: This case illustrates an unusual extensive presentation of TBVC with characteristic dermoscopic features. Dermoscopy can support early diagnosis, especially in endemic areas, allowing timely treatment and preventing complications.