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

Abstract

Background: Recently, microbiome research has been actively conducted for various skinareas. However, no study has yet compared the microbiome of bacteria and fungi in the earcanal of healthy individuals and patients with chronic otitis externa in Korea. Objective: This study aimed to investigate the difference in the distribution of fungal andbacterial microbial communities in ear canal samples of healthy individuals and patientswith chronic otitis externa. Methods: In 24 patients with bilateral chronic otitis externa and 24 healthy controls, cottonswabs were used to obtain samples from the bilateral ear canal. To characterize the fungaland bacterial communities, we sequenced and analyzed the 16S rRNA V4–V5 and ITS1 re-gions using Quantitative Insights into Microbial Ecology 2, respectively. Results: The alpha diversity analysis for bacteria and fungi confirmed that both richnessand evenness decreased in the patient group. The beta diversity analysis for bacteria con-firmed that these parameters differed between the control and patient groups. The beta di-versity analysis for fungi showed no difference between the groups. Conclusion: We observed different skin microbiomes in the patients with chronic otitis ex-terna compared with those in the healthy individuals.