Delayed diagnosis of chronic postoperative sternal infection: a rare case of sternal tuberculosis

Sternal osteomyelitis secondary to mycobacterium tuberculosis (TB) is rare, with <1% of musculoskeletal TB cases reported. The recurrent scenario is unresolving infection and delayed diagnosis. A 75-year-old woman presented with a persistently discharging sternal wound 10 months after coronary artery bypass grafting. Multiple antibiotics, wound debridement and removal of sternal wires was attempted; however, progression to local osteomyelitis and sternoclavicular joint destruction occurred. Tissue biopsies were finally sent for mycobacterial culture testing positive for Mycobacterium tuberculosis High index of suspicion is necessary for diagnosis of sternal tuberculosis, confirmed through timely microbiological investigations. MRI may identify soft-tissue and bone oedema characteristic of TB osteomyelitis. This patient had no TB risk factors. The source of infection is unclear and warrants further investigation. Sternal TB osteomyelitis is uncommon and largely reported through case reports, thus management and indications for surgery remain undefined. If sensitive, standard TB four-drug regimen may be trialled.