Kajol Shah

Introduction: Acute Otitis Media (AOM) is a middle ear infection that leads to over 5 million pediatric cases and 30 million healthcare visits annually in the US.¹ Pediatric populations are more likely to get infections because of eustachian tube anatomy, exposure to pathogens in the environment, and genetic differences in immune system activation.^1,2 Over 10 million yearly antibiotic prescriptions are given to pediatric patients in the US to treat AOM and the growing use of antibiotic treatment has subsequently increased bacterial resistance to antibiotics.¹ Antibiotics used to treat AOM disturb microbial flora and increase risk of colonization with resistant bacteria (particularly Streptococcus pneumoniae and Staphylococcus aureus).³ Therefore, an understanding of microbiota shifts in AOM could pave the way for potential non-antibiotic strategies to diagnose, prevent, and treat AOM. In this regard, we conducted a systematic review of the literature. Methods: Comparisons of nasopharyngeal microbiome were evaluated in healthy children and those that had recurring cases of AOM between 0-6 years of age.^4,5 Furthermore, factors such as duration of breastfeeding, antibiotic usage during pregnancy, and the effect of antibiotics on microbiota were evaluated.⁶ Results: Children with recurring cases on AOM were more likely to have infections between 6-12 months of age.⁴ Bacterial richness and beta dispersion increases with age whereas bacterial evenness decreases with age.⁵ There was a correlation between the length of time children were breastfed to the development of AOM where AOM-prone patients were breastfed for a shorter time.⁵ Additionally, when antibiotics were taken during the third trimester of pregnancy, children were more likely to develop AOM in the first 3 years of life and to need ventilation tubes for recurrent AOM treatment.⁶ Comparison of phylogeny of salivary bacterial communities showed that two distinct microbiota clusters formed between samples before Amoxicillin treatment and after.^7,8 Conclusion: There are certain factors such as age, environment, antibiotic treatment, and AOM onset that can cause changes to the NP and ME microbiome. These microbiota variations between healthy and at-risk AOM patients can potentially be used as a diagnostic tool and as a non-antibiotic therapeutic strategy to combat AOM. Potential therapies could include developing probiotics that mirror the microbiota of older children or replicating the microbiome of AOM-resistance children. By testing these treatment options, an optimal probiotic could be developed to reduce AOM infections and the need for antibiotics.

1. Kaur, , Morris, M., & Pichichero, M. E. (2017). Epidemiology of acute otitis media in the postpneumococcal conjugate vaccine era. Pediatrics, 140(3). https://doi.org/10.1542/peds.2017-0181
2. Atkinson, , Wallis, S., & Coatesworth, A. P. (2015). Acute otitis media. Postgraduate Medicine, 127(4), 386–390. https://doi.org/10.1080/00325481.2015.1028872
3. Schilder, G., Chonmaitree, T., Cripps, A. W., Rosenfeld, R. M., Casselbrant, M. L., Haggard, M. P., & Venekamp, R. P. (2016). Otitis media. Nature Reviews Disease Primers, 2(1). https://doi.org/10.1038/nrdp.2016.63
4. Xu, L., Earl, J., Bajorski, , Gonzalez, E., & Pichichero, M. E. (2021). Nasopharyngeal microbiome analyses in otitis-prone and otitis-free children. International Journal of Pediatric Otorhinolaryngology, 143, 110629. https://doi.org/10.1016/j.ijporl.2021.110629
5. Lappan, R., Imbrogno, K., Sikazwe, C., Anderson, D., Mok, D., Coates, H., Vijayasekaran, , Bumbak, P., Blyth, C. C., Jamieson, S. E., & Peacock, C. S. (2018). A microbiome case-control study of recurrent acute otitis media identified potentially protective bacterial genera. BMC Microbiology, 18(1). https://doi.org/10.1186/s12866-018-1154-3
6. Pedersen, M., Stokholm, J., Thorsen, J., Mora-Jensen, A.-R. C., & Bisgaard, H. (2017). Antibiotics in pregnancy increase children’s risk of otitis media and ventilation tubes. The Journal of Pediatrics, 183. https://doi.org/10.1016/j.jpeds.2016.12.046
7. Lazarevic, , Manzano, S., Gaïa, N., Girard, M., Whiteson, K., Hibbs, J., François, P., Gervaix, A., & Schrenzel, J. (2013). Effects of amoxicillin treatment on the salivary microbiota in children with acute otitis media. Clinical Microbiology and Infection, 19(8). https://doi.org/10.1111/1469-0691.12213
8. Brugger, D., Kraemer, J. G., Qi, W., Bomar, L., Oppliger, A., & Hilty, M. (2019). Age-dependent dissimilarity of the nasopharyngeal and middle ear microbiota in children with acute otitis media. Frontiers in Genetics, 10. https://doi.org/10.3389/fgene.2019.00555