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Updated: Aug 6, 2026
10:33
Primed Mycobacterial Uveitis (PMU) as a Model for Post-Infectious Uveitis
Published on: December 17, 2021
Mycobacterium avium Complex Presenting as Inferior Rectus Pyomyositis
Leo M Hall1, H Joon Kim, Robert C Kersten
1Department of Oculoplastic and Facial Plastic Surgery, John A. Moran Eye Center, University of Salt Lake City, Utah, U.S.A.
Ophthalmic Plastic and Reconstructive Surgery
|July 20, 2026
Summary
This case report details the first instance of pyomyositis caused by Mycobacterium avium complex in an immunocompetent patient, presenting with eye proptosis. It highlights rare NTM infections in the periocular region.
Area of Science:
- Ophthalmology
- Infectious Diseases
- Microbiology
Background:
- Non-tuberculous mycobacterium (NTM) infections typically affect immunocompromised individuals.
- Periocular and adnexal region infections by NTM are rare, despite systemic prevalence.
- Pyomyositis, or muscle infection, is an uncommon presentation for NTM.
Purpose of the Study:
- To report the first case of pyomyositis caused by Mycobacterium avium complex (MAC) in an immunocompetent patient.
- To review existing literature on extraocular muscle pyomyositis and NTM infections in the periocular region.
- To emphasize that NTM can infect immunocompetent hosts and cause rare conditions like pyomyositis.
Main Methods:
- Case report presentation.
- Surgical drainage of a "cold abscess" in the inferior rectus muscle.
- Prolonged medical treatment for NTM infection.
- Literature review of relevant cases and NTM infections.
Main Results:
- An immunocompetent patient presented with progressive proptosis due to a "cold abscess" in the inferior rectus muscle.
- The abscess was caused by Mycobacterium avium complex, a rare cause of pyomyositis.
- Successful management involved surgical intervention and extended antimicrobial therapy.
Conclusions:
- Non-tuberculous mycobacterium infections, including pyomyositis, can occur in immunocompetent individuals.
- Ophthalmologists and infectious disease specialists must collaborate for managing these challenging infections.
- Early recognition and comprehensive treatment are crucial for eradicating fastidious organisms like MAC.
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