Isolated sacral and pelvic TB abscess—an enigmatic tale of a ubiquitous pathogen

A 45-year-old male from a remote village in Nepal presented to our outpatient clinic with a history of intractable backache since last 1 year. He had history of weight loss but no positive history of trauma, fever, chills, rigor, altered bladder and bowel habits. He had no previous contacts to tuberculosis. General examination did not reveal any lymphadenopathy or neurological deficits. He was immunocompetent. Computerized tomogram (CT) of the lumbo-sacral (LS) spine revealed the presence of lytic lesion in the LS junction (Fig. 1). Magnetic resonance imaging (MRI) revealed presacral and left pelvic collection with destruction of the L5-S1 space with signal changes in the upper vertebral bodies as well (Fig. 2). His chests X-ray, ultrasound of the abdomen, serum calcium, alkaline phosphatase were normal. Monteux test was also negative. Erythrocyte sedimentation rate and C reactive protein were slightly elevated. Ultrasound-guided