Coinfection meningitis caused by Lysinibacillus sphaericus and Brevundimonas diminuta in a pediatric patient with cerebral atrophy: a case report.

BACKGROUND

Intracranial infections caused by rare environmental pathogens pose diagnostic and therapeutic challenges. This report presents the first documented case of meningitis caused by coinfection with Lysinibacillus sphaericus and Brevundimonas diminuta.

CASE PRESENTATION: A 10-year-old Han Chinese, nonverbal male with cerebral atrophy developed fever and vomiting following Ommaya pump implantation. Cerebrospinal fluid (CSF) culture and preliminary matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) suggested coinfection with L. sphaericus and B. diminuta, which was subsequently confirmed by 16S rRNA gene sequencing. Initial vancomycin monotherapy failed, but treatment was successfully switched to intravenous meropenem combined with intrathecal gentamicin via the Ommaya pump.

CONCLUSIONS

This case highlights that even immunocompetent hosts with indwelling neurological devices are susceptible to opportunistic infections by environmental pathogens. Molecular diagnostic techniques are crucial for confirming rare pathogens, and intrathecal administration can serve as a vital adjunctive strategy when systemic therapy is ineffective.