MAMC doctors report a rare case of isolated primary cold abscess of the sternum

Dr Lovenish Bains at the Department of Surgery, Maulana Azad Medical College, New Delhi, India, and colleagues have reported a rare case of isolated primary cold abscess of the sternum. The case has appeared in the Journal of Medical Case Reports.

Musculoskeletal tuberculosis forms 10–25% of extrapulmonary tuberculosis which mainly involves the spine or weight-bearing joints. Tuberculous involvement of the sternum is a rare clinical entity even in countries where tuberculosis has a high prevalence. Primary tuberculous sternal osteomyelitis accounts for approximately 0.3% of all types of tubercular osteomyelitis and the probable source appears to be an extension from paratracheal or hilar lymph nodes. Despite tuberculosis being a common disease in endemic countries and worldwide, a thorough literature search of the PubMed database for keywords “primary tuberculosis of sternum” and “primary tuberculous osteomyelitis of sternum” yielded 30 and 22 articles, respectively.

Courtesy Journal of Medical Case Reports

The authors have reported an unusual case of a large dumb-bell-shaped cold abscess arising due to infection of the sternum. A 23-year-old immunocompetent Asian woman presented with a gradually progressing painless swelling on the anterior chest wall for the last 5 months. She had a large visible swelling on anterior chest wall which was 12.5 cm in diameter, the soft, non-tender, temperature was not raised, and fluctuant. Magnetic resonance imaging showed a large dumb-bell-shaped hyperintense collection in the upper anterior chest wall with marrow oedema and cortical irregularity in the left side of the manubrium. Pus was positive for nucleic acid testing (cartridge-based nucleic acid amplification test) for Mycobacterium tuberculosis and later culture was also positive. She was started on anti-tubercular therapy and aspirated twice. Currently, she has completed 6 months of therapy and the swelling has now disappeared.

Swelling, pain localized to sternum, or ulceration of the skin with discharging sinus along with or without constitutional symptoms are the usual presentation. A high element of suspicion is needed for early diagnosis and treatment to prevent its complications. Sternal mycobacterial infections are categorized as primary, secondary, and/or acquired postoperatively. Although radiological investigations aid in diagnosis, the diagnosis is established by positive culture or histopathological examination. Anti-tubercular therapy is the mainstay of treatment with standard four-drug regimen for 6–9 months. Surgical drainage of the abscess should be considered only if it does not resolve by aspiration and anti-tubercular therapy.

To read the case report in detail follow the link: https://doi.org/10.1186/s13256-019-2210-9