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Published on: July 3, 2025
Paediatric Mycobacterium Avium Complex Otomastoiditis: Case Series and Literature Review
Alexandra M Wilson1, Claire Iseli2
1Otolaryngology, The Royal Melbourne Hospital, 300 Grattan St, Parkville VIC 3050, Australia.
Insights
Two pediatric cases of Mycobacterium avium complex (MAC) mastoiditis were successfully treated with antimycobacterial agents and surgery. This highlights the importance of considering atypical pathogens in resistant mastoiditis cases.
Area of Science:
- Otolaryngology
- Infectious Diseases
- Pediatric Medicine
Background:
- Mastoiditis is a common complication of otitis media.
- Resistant mastoiditis cases may involve atypical pathogens.
- Mycobacterium avium complex (MAC) is an opportunistic pathogen.
Abstract:
This case series details two paediatric cases of Mycobacterium avium complex (MAC) mastoiditis that presented to the same hospital within three years of each other and were successfully managed. One female and one male patient, both pre-school aged, presented with otorrhoea and postauricular oedema unresponsive to intravenous antibiotics. Imaging demonstrated opacification of the mastoid air cells and middle ear with cortical breaks, and surgical exploration revealed granulation tissue in the mastoid cavity and antrum on gross and histopathological examination, as well as bony dehiscence. Mycobacterial culture revealed acid fast bacilli and polymerase chain reaction confirmed MAC infection. Both children received antimycobacterial agents and mastoidectomies. This series highlights the importance of considering atypical organisms when managing resistant mastoiditis, especially given the outcomes of sub-optimal management (such as conductive hearing loss, facial nerve palsy and meningitis). We suggest effective management based on our cases and the literature.
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