Changes in the epidemiology of acute mastoiditis according to the implementation of pneumococcal vaccination in a Spanish population.

INTRODUCTION

Our aim was to describe the epidemiology of acute mastoiditis (AM) in a pediatric population according to the implementation of the pneumococcal conjugate vaccines (PCV).

METHODS

Retrospective, observational study including children diagnosed with AM between January 2000 and December 2019 at a tertiary hospital in Madrid (Spain). The study was grouped into four 5-year periods (2000-2004, 2005-2009, 2010-2014, 2015-2019). The percentage change in the incidence rate was estimated to characterize trends.

RESULTS

Two hundred nineteen episodes from 209 patients were included. The incidence rate of AM remained stable during the study period, with an average of 2.2 cases/10,000 emergency department visits/year. There was a significant decrease in the prevalence of Streptococcus pneumoniae. Streptococcus pyogenes was the main microorganism isolated in the last study period.

CONCLUSIONS

The incidence of AM remained stable, although the prevalence of S. pneumoniae decreased in the post-PCV era, being S. pyogenes the main microorganism isolated after the implementation of PCV13.