Malin Ising - Institutionen för kliniska vetenskaper, Lund

Title: Uncomplicated and complicated acute otitis media – bacteriology, risk factors and hearing impairment.

Main supervisor: Marie Gisselson-Solén

Reviewers: Fredrik Resman, Per-Olof Eriksson

Abstract

Background

Acute otitis media (AOM) is the most common bacterial infection in children. It is less common in adults, but when it does occur, the infection is more severe. Most cases resolve spontaneously, however, some episodes lead to life-threatening complications. It is still unclear why some patients develop complications and whether there are risk factors that should call for more active treatment.

AOM develops when colonizing bacteria in the nasopharynx go from being apathogenic to becoming pathogenic when the host encounters a respiratory viral infection. During the COVID-19 pandemic, restrictions were introduced to limit the spread of the Sars-CoV-2 virus, but also led to a reduction in other types of viral infections. These restrictions gave us a unique possibility to study the interactions between viral and bacterial infections, and the effects of preventive measures on the spread of infectious diseases.

Research questions

1. To study the clinical importance and bacteriology of nasopharyngeal cultures performed in children with AOM
2. To map the incidence of AOM and its associated complications before, during and after the COVID-19- pandemic
3. To identify risk factors for developing complications to AOM

Preliminary results

The most common reason for a nasopharyngeal culture in children with AOM was recurrent AOM (40%). The most commonly identified pathogens were M. catarrhalis (53%) and

H. influenzae (30%).

The incidence of AOM is highest in children < 2 years. Mastoiditis is the most common complication. The incidence of AOM and associated complications were almost halved during the COVID-19 pandemic. After the pandemic, the incidence of AOM has almost reached pre-pandemic levels, whereas complications have increased two-fold in the most affected age groups.

A prospective case-control study on complications to AOM is ongoing, and, at present, just over 200 of the expected 300 cases have been included.

Significance

Due to its high prevalence, the treatment of AOM has a great impact, not only on individual patients, but also on antibiotic pressure. Improved knowledge about risk factors for complications can help us tailor treatment better in the future.

Published studies

Jinhage M, Hermansson A, Gisselsson-Solén M. Nasopharyngeal cultures in children with AOM - A retrospective study on bacteriological findings and impact on management. Int J Pediatr Otorhinolaryngol. 2021 Oct;149:110848. doi: 10.1016/j.ijporl.2021.110848. Epub 2021 Jul 19. PMID:

34304116.

Manuscripts

Ising M, Li H, Santosa A, Nyberg F, Gisselsson-Solén M. The incidence of AOM and its associated complications before, during and after the COVID-19-pandemic.