Background: Flavobacterium lindanitolerans, a Gram-negative rod first isolated from soil samples in 2008, is an extremely rare human pathogen, with only a few reports of infection in humans. Here, we present the second case of meningitis caused by this species.

Case Report: A 65-year-old male presented to the Emergency Room with a sudden onset of headache and posterior nasopharyngeal discharge. Computed tomography (CT) scan revealed a fistula in the anterior cranial fossa, resulting in pneumocephalus. The patient subsequently developed a fever and signs of meningism. A lumbar puncture was performed, and the cerebrospinal fluid (CSF) analysis demonstrated an increased leukocyte count, elevated protein levels, and the presence of Gram-negative rods. Bacterial meningitis was diagnosed, and the patient was started on empiric antibiotic therapy. Bacterial colonies were sent to a national reference laboratory for automated identification, which confirmed the species as Flavobacterium lindanitolerans.

Conclusions: This is only the fourth reported case of F. lindanitolerans identified in human samples since its discovery. Our patient fully recovered after surgical correction of the anterior fossa fistula, which was considered as a possible route of bacterial entry, and a 14-day course of treatment with ceftriaxone. This case highlights the role of F. lindanitolerans as a potential infectious agent.