# A tympanitis-related brain abscess caused by Helcococcus kunzii in China: a case report and literature review

## TL;DR

This paper reports the first case of a brain abscess caused by Helcococcus kunzii in China, emphasizing the importance of accurate diagnosis and treatment of such rare infections.

## Contribution

The study presents the first documented case of a brain abscess caused by H. kunzii in China and highlights its clinical significance.

## Key findings

- A 54-year-old patient with tympanitis developed a brain abscess caused by H. kunzii.
- The H. kunzii strain was resistant to erythromycin and clindamycin but successfully treated with ceftriaxone, meropenem, and norvancomycin.
- MALDI-TOF MS and 16S rRNA sequencing confirmed the presence of H. kunzii and two anaerobic bacteria.

## Abstract

Infections attributed to Helcococcus kunzii are rarely documented, especially in relation to brain abscesses. This study aims to report the first documented case of a brain abscess associated with tympanitis caused by H. kunzii in China, alongside a comprehensive review of the existing literature.

We detail the case of a 54-year-old female patient with a history of hypertension, who was diagnosed with tympanitis complicated by a brain abscess. An urgent occipital lobectomy was performed, during which pus was collected for culture analysis. Three distinct colony morphologies were identified through matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) analysis, including H. kunzii and two additional anaerobic bacterial species. Subsequent biochemical assays and 16S rRNA gene sequencing corroborated the presence of H. kunzii. Antimicrobial susceptibility testing revealed that the isolated H. kunzii strain exhibited resistance to erythromycin and clindamycin. The patient was subsequently treated with intravenous antibiotics, specifically ceftriaxone, meropenem, and norvancomycin, resulting in complete recovery.

This case underscores the increasing acknowledgment of H. kunzii as a notable pathogen in invasive intracranial infections. It is imperative for clinicians to consider H. kunzii in the differential diagnosis of patients presenting with intracranial infections, especially those with a history of tympanitis, to ensure prompt and effective management. The utilization of MS and molecular techniques should be prioritized for the accurate identification of these anaerobic bacteria.

The online version contains supplementary material available at 10.1186/s12879-025-10895-6.