Characterization of the Ear Canal Bacterial Flora Present in Hearing Aids (HA) Wearing Subjects
Characterization of the Ear Canal Bacterial Flora Present in Hearing Aids (HA) Wearing Subjects作者机构:Department of Public Health and Infectious Diseases “Sapienza” University of Rome Rome Italy Dani Di Giò Foundation-Onlus Rome Italy Department of Medical Oral and Biotechnological Sciences University “G. D’Annunzio” Chieti Italy Institute of Otolaryngology “Cattolica del Sacro Cuore” University Agostino Gemelli Polyclinic Rome Italy Otolaryngology Mater Olbia Hospital Olbia Italy Department of Public Health and Infectious Diseases “Sapienza” University of Rome Laboratory Affiliated to Institute Pasteur Italia Cenci-Bolognetti Foundation Rome Italy San Raffaele Pisana IRCCS Telematic University Rome Italy
出 版 物:《Advances in Microbiology》 (微生物学(英文))
年 卷 期:2019年第9卷第7期
页 面:616-628页
学科分类:1002[医学-临床医学] 100214[医学-肿瘤学] 10[医学]
主 题:Ear Bacterial Flora Hearing Aids Acute Otitis Externa
摘 要:The use of hearing aids (HA) is considered a predisposing factor for ear microbial infections. We undertook this study to compare the presence and nature of the microbial flora inhabiting of ears of HA and non-HA (nHA) users. Swab samples of the ears of HA and nHA users were collected from the Institute of Otolaryngology, “Cattolica del Sacro Cuore University “Agostino Gemelli, Rome, Italy. Swab samples were taken from the ear canal of 57 HA and 33 nHA users. The components of the microbial flora present on each swab sample were identified and characterized at the level of species. A total of 41 different bacterial species were identified. A statistically significant prevalence of polymicrobial communities was found in ears presenting signs of inflammation (2.5 ± 1.7 vs 2.1 ± 1.3;P = 0.02) and in HA users (2.3 ± 1.2 vs 1.7 ± 1.0;P = 0.002). Few putative pathogens were detected. Candida albicans spp. was not isolated in our study. A small number of swab samples presented no microbial growth. Bacterial species isolated from HA users with and without inflammation were assayed for the ability to form biofilm. Among gram-positive and gram-negative bacteria, S. aureus, CoNS, P. aeruginosa and K. pneumoniae were found to be strong biofilm producers. S. aureus and P. aeruginosa, isolated only from the ears of HA and nHA users presenting signs of inflammation, were further analyzed for their antibiotic-resistance profile and characterized by the Multilocus Sequence Typing (MLST) assay. The highest rates of antibacterial resistance were in S. aureus to penicillin (75.5%) and in P. aeruginosa, to amoxicillin-clavulanic acid, cefotaxime, ertapenem, tigecycline and trime-thoprim-sulfamethoxazole (100%). Moreover, three S. aureus strains (37.5%) were methicillin-resistant (MRSA). Of the eight S. aureus isolates, we identified six sequence types (ST) indicating that 75% are likely independent clones. For what it concerned P. aeruginosa, six different STs were assigned. Interesti