Tuberculosis of the patella masquerading as prepatellar bursitis

Ambiguity of Primary Patellar Tuberculous Osteomyelitis as a Pre-Patellar Bursitis: A Case Report

CASE

A 47-year-old male with swelling over the patella and associated pain, subsiding with medicines but recurring after a few days. Diagnosed as prepatellar bursitis by the family physician, it eventually turns out to be osteomyelitis of the patella. Treated with curettage, biopsy, and placement of bio-composite mixed with antibiotics. Intra-operative findings and histopathology confirmed tuberculosis of the patella. On follow-up after 6 years and the completion of anti-tuberculosis treatment, the patient showed full functional and radiological recovery without recurrence.

CONCLUSION

Early treatment with antibiotics and surgery gives excellent results. Identifying it as a tuberculous osteomyelitis is challenging when the condition is closely resembles pre-patellar bursitis.

Primary patella tuberculosis mimicking pre-patellar bursitis: A case report and review of the literature

Introduction and importance

The Patella is very rare site for tuberculosis (TB). The knee is the third most common site for skeletal TB. The incidence of patella TB being 0.09 to 0.15%.

Case presentation

We report a case of primary tuberculous osteitis isolated from the patella. The complaint was a mixed knee pain without notion of trauma. The CT showed a large osteolysis of the upper half of the patella. The diagnosis was established on the histological study after biopsy. The patient was operated by a medial approach without arthrotomy and the pathological tissue was resected and curetted. Complementary anti-bacillary antibiotic treatment was administered for 12 months. At the last clinical control, the knee was free and painless, and we had no recurrence.

Clinical discussion

Aitken reported the first case in literature in 1933. The initial signs and symptoms are non-specific and sometimes confounded by a coincidental history of trauma. It is difficult to diagnose TB of patella in early stages because there are no constitutional symptoms. Sometimes serological parameters are inconclusive. CT scan can help if the osteolysis contained a central bone sequestration, bordered by peripheral sclerosis. Confirmation of patellar tuberculosis is made on biopsy.

Conclusion

The tuberculous localization in the patella is rare and it can pose a problem of differential diagnosis with other affections, in particular infectious and tumors. It should always be kept in mind, especially in the face of a picture of pre-patellar bursitis which progresses slowly and whose biological inflammatory syndrome is not straightforward.

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The tuberculous localization in the patella is exceptional.

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The initial signs and symptoms are non-specific and sometimes confounded by a coincidental history of trauma.

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This serological parameters are inconclusive.

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CT scan can help if the osteolysis contained a central bone sequestration, bordered by peripheral sclerosis.

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Confirmation of patellar tuberculosis is made on biopsy.

Prepatellar Bursal Infection Caused by Mycobacterium tuberculosis with an In Situ Total Knee Arthroplasty: A Case Report and Comprehensive Literature Review

Prepatellar bursal infection is a rare occurrence. The incidence of tuberculosis, including musculoskeletal type, is increasing. We present a case of isolated prepatellar bursal swelling associated with a discharging sinus; the condition developed in an elderly patient 4 years after total knee arthroplasty. Aspiration of the bursa revealed acid-fast bacilli on Ziehl–Neelsen staining, typical of Mycobacterium tuberculosis; this was confirmed later on culture. The patient was successfully treated with a 6-month course of antituberculous chemotherapy. To the best of our knowledge, only two previous cases of tuberculous prepatellar bursal infection have been reported in English literature. Our case illustrates the importance of considering tuberculous prepatellar bursal infection in the differential diagnosis of anterior knee swelling. All physicians treating patients with musculoskeletal disease should be aware of the possibility of this diagnosis and maintain a high index of suspicion; this is especially true in areas where tuberculosis is still endemic and in high-risk patients, such as the elderly.

Tuberculosis of the Knee: A Case Report and Literature Review

Tuberculosis (TB) is currently in resurgence due to immigration from endemic areas. Skeletal TB frequently mimics more common etiologies and can be difficult to diagnose. A case of TB knee arthritis in a young woman with painful and swelling knee is reported here. Arthrotomy was performed and inflamed synovial tissue was found, with multiple rice bodies in the eroded lateral femoral condyle. The patient was treated with an antituberculosis polytherapy and at 1-year follow-up, she reported relief from pain and swelling. We believe that all surgeons assessing patients from TB endemic regions have to adopt an updated approach to TB treatment. Thus, a literature review is also reported here on the current strategies used in different knee TB cases.

Bilateral patellar tuberculosis masquerading as infected infrapatellar bursitis

A 30-year-old woman presented to our outpatient department with complaints of pain and swelling in bilateral infrapatellar regions and a discharging sinus in the right knee over the duration of one year. Radiographs showed lytic regions in bilateral patellae. Samples sent from material curetted from sinus yielded no organism but histopathology reported granulomatous inflammation. Following a fresh magnetic resonance imaging (MRI) scan that revealed the infrapatellar pad of fat communicating with the patellar lesions, an exploration and evacuation was done. Material sent revealed epithelioid cell granulomas with caseous necrosis consistent with tuberculosis (TB). The patient was put on first line anti-tubercular treatment (ATT) and has responded favourably with healing of sinus and patellar lesions. Bilateral infrapatellar bursitis is not rare. However patellar TB as a cause for OMIT is not a common diagnosis. A bilateral patellar involvement has not been reported in literature to the best of our knowledge.