Analysis of the Microbiome of the Ear Canal in Normal Individuals and Patients with Chronic Otitis Externa

Recently, microbiome research has been actively conducted for various skin areas. However, no study has yet compared the microbiome of bacteria and fungi in the ear canal of healthy individuals and patients with chronic otitis externa in Korea. This study aimed to investigate the difference in the distribution of fungal and bacterial microbial communities in ear canal samples of healthy individuals and patients with chronic otitis externa. In 24 patients with bilateral chronic otitis externa and 24 healthy controls, cotton swabs were used to obtain samples from the bilateral ear canal. To characterize the fungal and bacterial communities, we sequenced and analyzed the 16S rRNA V4-V5 and ITS1 regions using Quantitative Insights into Microbial Ecology 2, respectively. The alpha diversity analysis for bacteria and fungi confirmed that both richness and evenness decreased in the patient group. The beta diversity analysis for bacteria confirmed that these parameters differed between the control and patient groups. The beta diversity analysis for fungi showed no difference between the groups. We observed different skin microbiomes in the patients with chronic otitis externa compared with those in the healthy individuals.