Chronic suppurative otomastoiditis due to nontuberculous mycobacteria: A case series

Eight new cases of chronic otomastoiditis due to nontuberculous mycobacteria were reported at Center Hospitalier Universitaire Sainte-Justine (CHUSJ) between 2008 and 2018. In the literature, only 89 cases have been described since 1972. This case series aims to define the clinical presentation, infectious pathogens, as well as diagnostic and therapeutic means employed in cases of nontuberculous mycobacteria otitis media encountered in our tertiary pediatric reference center.

All cases of otitis media caused by nontuberculous mycobacteria diagnosed at Sainte-Justine between 2008 and 2018 were reviewed. Species identification was retrieved from the Laboratoire de Santé Publique du Québec, Quebec's provincial public health and reference laboratory.

All 8 cases occurred in immunocompetent children. Clinical features on presentation were chronic tympanostomy tube otorrhea with abundant granulation tissue in 7 cases. CT scan demonstrated coalescent mastoiditis in 3 cases. The median delay between initial presentation and identification of nontuberculous mycobacteria was 81 days. Seven patients had a Mycobacterium (M.) abscessus complex infection. Treatment consisted of weekly microscopic granulation debridement, a combined systemic antibiotic therapy for an average duration of 21 weeks, as well as instillation of boric acid into the middle ear. While 3 cases required at least one mastoidectomy, 2 cases were treated only medically.

Nontuberculous mycobacteria otitis media is a rare clinical entity, for which high clinical suspicion and specific microbiological analyses could minimize diagnostic delay. The use of boric acid as a desiccating agent may allow for a better local control.