Candida tropicalis Brain Abscess Diagnosed by Metagenomic Next-generation Sequencing.

We report the case of a 59-year-old HIV-negative male diagnosed with a brain abscess following vasculitis-associated stroke. The causative pathogen remains unidentified using conventional methods including culture and rapid multiplex PCR. Craniotomy and biopsy were performed to establish a definitive diagnosis, and metagenomic next-generation sequencing (mNGS) of the abscess tissue identified Candida tropicalis as the causative pathogen. This case highlights the utility of mNGS in identifying pathogens in culture-negative CNS infections, even when conventional methods fail to detect the causative agent, particularly when evaluating abscess pus.