Trends in Clinico-radiological and Laboratory Characteristics of All-Cause Meningoencephalitis in Western Rajasthan.

Background and objectives: Meningoencephalitis encompasses the coexistence of meningitis and encephalitis in different proportions. This study aimed to delineate the clinical profile, laboratory parameters, radiological features, and outcome predictors of patients with meningoencephalitis.

Methods: This prospective, observational, and descriptive study was conducted from July 2021 to March 2023. Patients satisfying the case definition of "meningitis" and "encephalitis" were enrolled. Mortality and morbidity (by modified Rankin Score [mRS]) were noted at discharge and at 1 and 3 months post-discharge.

Results: Of 102 patients recruited, among infectious meningoencephalitis cases, 28 (27.5%) were viral, 11 (10.8%) were pyogenic, 32 (31.4%) were tubercular, four (3.9%) each were rickettsial, atypical bacterial, and fungal, and three (2.9%) were parasitic. Among noninfectious etiologies, 12 (11.8%) were antineuronal antibody mediated, three (2.9%) had systemic inflammatory etiology, and one (1%) had carcinomatous meningitis. Cerebrospinal fluid (CSF) analysis showed the highest protein content (336.82 ± 251.26 mg/dL) and cell count (476.73 ± 999.16/mm3) in pyogenic followed by tubercular (200.29 ± 174.28/mm3) meningoencephalitis. CSF glucose was lowest in tubercular group (38.30 ± 20.29 mg/dL). Imaging showed leptomeningeal enhancement predominantly in tubercular group (89.7%) and limbic involvement in viral etiology (38.5%). Overall mortality was highest in fungal and rickettsial groups (three out of four patients died at 1 month in each group). Pyogenic, atypical bacterial, and systemic inflammatory meningoencephalitis had maximum temporal improvement in mRS at 1 month, while tubercular, viral, and antineuronal antibody-mediated meningoencephalitis had decrease of at least 1 mRS at 3 months. Fever, altered sensorium, speech disturbances, neck stiffness, albumin, total leukocyte count, erythrocyte sedimentation rate, C-reactive protein, kidney and liver function tests showed significant association with mortality.

Conclusions: Tubercular, followed by viral meningoencephalitis, was the most common cause in our center in western India. Pyogenic, atypical bacterial, and systemic inflammatory groups had the best recovery at discharge, while fungal and rickettsial meningoencephalitis groups had worst mRS at 3 months.