Molecular Microbiological Profile of Chronic Suppurative Otitis Media

Abstract

bChronic suppurative otitis media (CSOM) presents with purulent otorrhea (ear discharge), is characterized by chronic inflammation of the middle ear and mastoid cavity, and contributes to a significant disease burden worldwide. Current antibiotic therapy is guided by swab culture results. In the absence of detailed molecular microbiology studies of CSOM patients, our current understanding of the microbiota of CSOM (and indeed of the healthy ear) remains incomplete. In this prospective study, 24 patients with CSOM were recruited, along with 22 healthy controls. Culture-based techniques and 16S rRNA gene amplicon sequencing were used to profile the bacterial community for each patient. Comparisons between patients with and without cholesteatoma in the middle ear and mastoid cavity were also made. A major finding was that the middle ear of many healthy controls was not sterile, which is contradictory to the results of previous studies. However, sequencing data showed that Staphylococcus aureus, along with a range of other Gram-positive and Gram-negative organisms, were present in all subgroups of CSOM and healthy controls. Large interpatient variability in the microbiota was observed within each subgroup of CSOM and controls, and there was no bacterial community "signature" which was characteristic of either health or disease. Comparisons of the culture results with the molecular data show that culture-based techniques underestimate the diversity of bacteria found within the ear. This study reports the first detailed examination of bacterial profiles of the ear in healthy controls and patients with CSOM.

Next-Generation Sequencing Combined with Specific PCR Assays To Determine the Bacterial 16S rRNA Gene Profiles of Middle Ear Fluid Collected from Children with Acute Otitis Media

“…Recently, Neeff et al utilized nested PCR in the characterization of bacteriome profiles in 24 predominantly adult patients with chronic suppurative otitis media (71% with cholesteatoma) and 22 healthy control ears (15). Thus, the present study is a significant contribution to the field, being the largest 16S profiling study of otitis media and the only one of AOM so far.…”

A study of bacterial pathogens and antibiotic susceptibility patterns in chronic suppurative otitis media

“…1,2 The infection is characterised by chronic inflammation of the middle ear and mastoid cavity, with tympanic membrane perforation. Chronic suppurative otitis media most often occurs in the first 6 years of life, and contributes to a significant disease burden worldwide, estimated at 65-330 million people, with 28 000 deaths per annum.…”

The unsolved problem of otitis media in indigenous populations: A systematic review of upper respiratory and middle ear microbiota in indigenous children

“…Commensurate with this result, culture-based literature from non-indigenous children with CSOM often report P. aeruginosa and S. aureus in MED [60–65]. 16S rRNA gene sequencing of MED from children and adults with CSOM in New Zealand further detected Alloiococcus and Streptococcus [66]. In the CSOM studies included in this review, Alloiococcus would not have been detected, if present, as the specialist culture conditions or PCR required to detect this species were not used.…”