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

BACKGROUND: 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. CASE PRESENTATION: 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. CONCLUSIONS: 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.