# Acute mastoiditis caused by Klebsiella pneumoniae carbapenemase (KPC) producing bacteria – an atypical cause

## TL;DR

This paper reports a rare case of acute mastoiditis caused by KPC-producing bacteria in an immunosuppressed adult.

## Contribution

The case highlights an atypical cause of acute mastoiditis not commonly reported in medical literature.

## Key findings

- Acute mastoiditis caused by KPC-producing bacteria is rare and typically occurs post-surgery or trauma.
- The patient was successfully treated with intravenous colistin based on antibiotic susceptibility testing.
- KPC infections are increasing, especially in immunosuppressed individuals, and carry high mortality and healthcare costs.

## Abstract

The aim of this report is to present a rare case of acute mastoiditis caused by Klebsiella (K.) pneumoniae carbapenemase (KPC) producing bacteria.

The following report describes a 78-year-old immunosuppressed female who was hospitalized due to left-sided acute otitis media complicated by tympanic membrane rupture and acute mastoiditis. Fluid-discharge culture revealed KPC. The patient successfully received four weeks of conservative treatment with intravenous colistin (based on antibiotic susceptibilities).

Acute mastoiditis is a rare complication of acute otitis media, mostly seen in pediatric populations. The most frequent causative agents identified are Gram-positive cocci such as Streptococcus (S.) pyogenes and S. pneumoniae. Acute mastoiditis caused by KPC-producing bacteria has rarely been reported in medical literature, with most such infections observed following neurosurgical surgeries and/or post-trauma.

The incidence of infection by KPC is rising, especially in immunosuppressed patients and those with recent and/or prolonged hospitalizations. There are very few reports in the literature describing acute mastoiditis caused by KPC. Infection with KPC not only has a high 30-day mortality rate (up to 40%) but also poses a significant financial burden on the healthcare system.