Mr. X, a 70-year-old male with a history of diabetes mellitus and chronic liver disease, presented with a one-month history of chest pain radiating to the left shoulder. The pain had progressively increased in intensity. He did not report any trauma or pain in other joints. On clinical examination, restricted range of motion and pain were observed in the left shoulder. No symptoms or signs from other systems or joints were noted.
Consultation with an orthopedist was sought, and a recommendation for a CT scan of the shoulder was made, small geodes in glenoid- degenerative . The CT scan of the chest, in light of the patient’s clinical features, suggested a differential diagnosis of tuberculosis (TB). As a result, both the Quantiferon Gold test and Mantoux test were performed, with negative results. An interventional radiologist performed an ultrasound-guided FNAC (fine needle aspiration cytology) of the left sternoclavicular joint, which revealed necrotizing granulomatous inflammation. The patient was started on antitubercular therapy and was discharged with regular monitoring of liver function tests.
Tuberculous arthritis is a rare but significant manifestation of extrapulmonary tuberculosis, primarily affecting the weight-bearing joints, with the spine being the most commonly involved site. Although the incidence of tuberculous arthritis has decreased with the advent of effective antitubercular therapy, it remains a critical consideration in the differential diagnosis of joint pain, particularly in endemic regions or in patients with risk factors such as immunosuppression, diabetes mellitus, and chronic liver disease, as seen in our case.
Tuberculous arthritis is caused by hematogenous dissemination of *Mycobacterium tuberculosis* (MTB) from a primary pulmonary or extrapulmonary focus, although in some cases, the joint may be the primary site of infection. The typical pathogenetic mechanism involves the direct invasion of the synovium and articular cartilage by MTB, leading to the formation of granulomas and, ultimately, joint destruction. The disease usually presents insidiously with nonspecific symptoms such as joint pain, swelling, and limited range of motion. In some instances, patients may experience systemic symptoms like fever, weight loss, and night sweats. The pain associated with tuberculous arthritis often has a gradual onset, as opposed to the acute pain seen in bacterial septic arthritis.
The involvement of the left sternoclavicular joint, as in our case, is unusual, as tuberculous arthritis most commonly affects the large weight-bearing joints like the hip and knee, and the spine (Pott’s disease)
The diagnosis of tuberculous arthritis can be challenging, as the clinical and radiological findings are often nonspecific and may overlap with other forms of arthritis, such as septic or rheumatoid arthritis. In our case, the CT chest raised strong suspicion of tuberculosis, but the negative results of the Quantiferon Gold and Mantoux tests did not rule out the diagnosis. Definitive diagnosis requires microbiological confirmation, which may include joint aspiration or biopsy. The FNAC of the synovium, guided by ultrasound in this case, revealed necrotizing granulomatous inflammation, which is pathognomonic for tuberculosis. This is considered the gold standard for diagnosis when cultures for MTB are not feasible or conclusive. Histopathological findings of granulomatous inflammation with caseating necrosis are strongly indicative of tuberculous arthritis.
Figure – Tuberculoid granuloma with prominent Langhans type giant cells at periphery of the granuloma
The management of tuberculous arthritis primarily involves the use of antitubercular therapy (ATT) as outlined by national guidelines. In cases where joint destruction has occurred, surgical intervention, including drainage or joint debridement, may be necessary.
The response to ATT is generally favorable, and the prognosis is excellent when the disease is diagnosed early and appropriately treated. However, delayed diagnosis or inadequate therapy can result in irreversible joint damage, deformities, and even systemic spread of the infection.
Tuberculous arthritis, though uncommon, should be considered in the differential diagnosis of any patient presenting with joint pain, particularly when there are risk factors such as diabetes, chronic liver disease, or a history of exposure to tuberculosis. A high index of suspicion, along with appropriate diagnostic tools such as synovial FNAC and radiological imaging, is critical for early diagnosis and effective treatment. Timely initiation of antitubercular therapy can prevent severe joint destruction and improve long-term outcomes.
1.Harrison’s Principles of Internal Medicine, 22th Edition. Tuberculosis. Chapter 178. McGraw-Hill Education. 2.Dheda K, et al. “Tuberculous arthritis.” *PubMed Central (PMC)*. Available at: [https://www.ncbi.nlm.nih.gov/pmc/articles/ PMC5072077/](https://www.ncbi.nlm.nih.gov/pmc/articles /PMC5072077/) 3.Saini I, et al. “Tuberculosis of the sternoclavicular joint: A case report and review of the literature.” *PubMed*. Available at: [https://pubmed.ncbi.nlm.nih.gov/27879796/](https://pubmed.ncbi.nlm.nih.gov/ 4.https://www.pathologyoutlines.com/topic/ lungnontumortb.html
Dr. Madhumitha R M, MBBS DNB General Medicine Resident) Kauvery Hospital, Chennai
Dr. Sivaram Kannan, MD (General Medicine), FRCP (Senior Consultant, Internal Medicine) Clinical Lead & Chief Consultant Physician Kauvery Hospital, Chennai
Dr. Mukunth K, M.S (Ortho), F.I.A (Ger), Exe. Hip. Fel (UK) Senior Consultant Kauvery Hospital, Chennai
