Tuberculous granuloma: a rare cause of a non-healing ulcer

A 78-year-old woman on ciclosporin for aplastic anaemia presented to her general practitioner with a 2 cm cystic swelling on the right side of her forehead. After a period of 8 months the lesion ruptured and, despite good wound care, failed to heal over a period of seven further months. Imaging demonstrated an invasive process and a biopsy was taken, which showed granulomatous inflammation that stained positively for mycobacteria. Further investigation with cross-sectional imaging revealed no other sites of disease. The only history of exposure to tuberculosis was 64 years prior to presentation. Differential diagnoses of mycetoma, autoimmune disease and non-tuberculous mycobacterial infection were considered, but culture confirmed tuberculosis. This case demonstrates an unusual presentation of isolated cutaneous tuberculosis in a patient with suppressed immune function.