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Published on: July 3, 2025
Atypical Mycobacterium infections of the upper extremity
Masataka Noguchi1, Yoshimichi Taniwaki, Toshikazu Tani
1Department of Orthopaedic Surgery, Kochi Medical School, Nankoku, Japan. noguchim@kochi-ms.ac.jp
Background:
We encountered five patients with atypical Mycobacterium infections in the upper extremity, and examined their outcomes.
Patients And Methods:
Two patients were male and three were female. The average patient age was 67 (range, 63-75) years. A wide synovectomy was performed to diagnose all cases followed by a therapeutic regimen of Rifampicin, Isoniazid, and Ethambutol.
Results:
The causative atypical organism was Mycobacterium marinum in three cases and Mycobacterium intracellulare in two cases. In one patient, inflammation recurred or did not disappear, and, therefore, three debridements were necessary. The average duration of antimicrobial therapy was 12 (range, 5-24) months. The average follow-up period was 26 (range, 5-66) months, and resolution had been achieved in all cases at the time of follow-up evaluation.
Conclusion:
Surgical debridement and appropriate mycobacterial culture or PCR method are critical to enable diagnosis and appropriate management.
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