Aspergillus otitis externa: A retrospective study of predisposing factors, treatment, and complications

Objectives

To study the predisposing factors, treatment, and complications of Aspergillus otitis externa.

Methods

A retrospective analysis of patients diagnosed with Aspergillus otitis externa at the Department of Otorhinolaryngology, Helsinki University Hospital, between January 2010 and December 2018 was performed.

Results

Of the 269 Aspergillus otitis externa (OE) patients, 96 developed otitis media (OM) and 7 developed mastoiditis. Antibiotic and steroid treatment and otological history were risk factors for Aspergillus OE. Systemic diseases and immunocompromising states were more common in mastoiditis patients. Repetitive ear cleaning and topical drugs are primary treatments, but systemic drugs and surgery were needed in resistant and invasive cases. Forty-five novel tympanic membrane (TM) perforations were reported. A strong association between Aspergillus species and final infection types was found; A. niger was the dominant species in OM and in novel TM perforations, whereas A. flavus and A. fumigatus caused mastoiditis. Some of the TM perforations persisted despite treatment. Permanent hearing impairment was associated with OM and mastoiditis.

Conclusion

As Aspergillus OE has the potential to cause acute and chronic complications, fungal OE should be suspected early on if the infection persists after conventional treatment. The identification of Aspergillus species could aid in spotting patients at risk for more severe disease and complications. Intensive local treatment is sufficient in most cases of OE and OM but effective topical antifungals are limited. Patients with Aspergillus OM and mastoiditis should be followed up for hearing impairment and permanent TM perforations after the infection resolves.

Level of evidence

Level 4 (The Oxford 2011 Levels of Evidence).