The Silent Masquerader: Primary Neuroleptospirosis Mimicking Pyogenic Meningitis in a Previously Healthy Young Man

Abstract

Leptospirosis rarely announces itself through the nervous system alone. Most cases are self-limited febrile illnesses, or, at the severe end, Weil's disease with jaundice and renal failure — an isolated CNS presentation is easy to mistake for bacterial meningitis. We describe a 32-year-old previously well man who developed status epilepticus days into a febrile illness following a bath in a village tubewell during the monsoon. His CSF showed neutrophilic pleocytosis with low glucose, indistinguishable from pyogenic meningitis, yet liver and kidney function stayed normal throughout. It was the exposure history, not the CSF report, that prompted leptospiral serology, IgM-positive twice, four weeks apart. MRI showed bilateral frontal FLAIR hyperintensities with an enhancing right ependymal nodule. He responded well to antibiotics, with near-normalisation of CSF by discharge. This case is a reminder that leptospirosis can present as isolated CNS infection, and exposure history can matter more than the CSF numbers themselves.