A rare case of scrofuloderma along with lupus vulgaris

Abstract

Cutaneous forms of tuberculosis (TB) are rare, comprising about 1-1.5% of all cases, and show a wide range of clinical manifestations. Here we present a case of a patient with left cervical ulcerated lymphadenopathy associated with a violaceous plaque in the area of the manubrium of sternum. We performed a biopsy of the plaque for histopathology, a polymerase chain reaction (PCR) to test for mycobacteria and a smear of the ulcerated lymph node. Histopathology results showed a dermal infiltrate consisting of epithelioid granulomas without necrosis, PCR was negative and the culture was positive for M. tuberculosis. We made the diagnosis of scrofuloderma associated with lupus vulgaris. The patient was treated with an anti-tuberculous therapy with clinical regression of the lesions. Our case emphasizes the importance of recognizing that tuberculosis can occur as a primary cutaneous pathology, with a challenging diagnosis that requires the correlation of clinical findings with diagnostic testing.