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Mycobacterium avium/Mycobacterium intracellulare Complex-Associated Arthritis Masquerading as a Seronegative
1Division of Rheumatology, Department of Internal Medicine.
Summary
Mycobacterium avium/Mycobacterium intracellulare complex (MAC) can cause chronic tenosynovitis. Prompt diagnosis and triple antibiotic therapy resolved a patient's severe, treatment-resistant synovitis.
Area of Science:
- Rheumatology
- Infectious Diseases
- Microbiology
Background:
- Mycobacterium avium/Mycobacterium intracellulare complex (MAC) is an uncommon cause of tenosynovitis.
- Bilateral symmetric synovitis can mimic autoimmune arthritis, leading to delayed diagnosis of infectious causes.
Purpose of the Study:
- To report a case of chronic, treatment-resistant tenosynovitis caused by MAC.
- To highlight the importance of considering MAC in the differential diagnosis of inflammatory arthritis.
Main Methods:
- A case study describing a patient with progressive, bilateral symmetric tenosynovitis.
- Diagnosis was confirmed by synovial fluid culture for MAC after failure of DMARDs and synovectomy.
- Treatment involved cessation of DMARDs and 24 months of triple antibiotic therapy.
Main Results:
- The patient's synovitis resolved within 7 months of antibiotic treatment.
- The patient remained asymptomatic two months after completing therapy.
- This case underscores the potential for MAC to present as seronegative symmetrical inflammatory arthritis.
Conclusions:
- MAC should be considered in the differential diagnosis of seronegative symmetrical inflammatory arthritis, especially when refractory to conventional treatments.
- Early microbiological investigation is crucial for diagnosing MAC-induced tenosynovitis.
- Successful treatment of MAC tenosynovitis can be achieved with prolonged triple antibiotic therapy.
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