Etiological Agents of Infective Meningitis and Encephalitis Among Patients Admitted at Mbagathi County Hospital and Kenyatta National Hospital

Abstract

Background: Meningitis and encephalitis (ME) are associated with significant morbidity and mortality in the Kenyan population. HIV infection, universal roll-out of HAART, introduction of universal vaccination and emergence of zoonoses are believed to have changed the local CNS pathogen landscape. There are inadequate local data on the etiology of infective ME. This study sought to describe the etiological agents and clinical characteristics of infective ME, a clearer understanding of which may lead to better patient management and improved outcomes. Objective: To determine the etiology and clinical manifestations of infective meningitis and encephalitis among patients admitted at Mbagathi County Hospital and Kenyatta National Hospital (KNH). Methods: This was a descriptive cross-sectional study carried out between April and September 2023 at the Mbagathi County Hospital and KNH. Consecutive sampling was used to enroll patients aged 13 years and above who presented with signs and symptoms of ME. Cerebrospinal fluid (CSF) was collected. Investigations done included CSF protein and glucose concentrations, cell count, microscopy, culture and sensitivity, Cryptococcal antigen test, M. tuberculosis nucleic acid amplification test and multiplex PCR. Serum Toxoplasma IgG and IgM were carried out when clinically indicated. Statistical analysis was done using SPSS version 23.0. Comparisons of means was tested using Student’s ttest while medians were compared between groups using Mann Whitney U test. Associations involving categorical variables were tested using Chi square test and Fisher’s exact test. Statistical significance was interpreted at 5% level. Results: 100 participants were recruited. 55% were male and 59% were enrolled at KNH. Median age was 35.5 (15-94) years. 56% of patients were HIV positive. 73% of patients had altered mental status. Other signs and symptoms included headache (65%), neck stiffness (56%), seizures (34%), photophobia (22%) and fever (18%). C. neoformans, viral infections, acute bacterial infections, M. tuberculosis and T. gondii accounted for 40%, 21%, 19%, 14% and 5% of pathogens detected. The commonest cause of acute bacterial meningitis was E. faecalis (38%). N. meningitides, S. pneumoniae, H. influenza, CoNS and S. viridans each accounted for 13%. Viruses detected included HSV1, HSV2, VZV, HHV6, HHV7 and CMV. HHV7 and HHV6 were the commonest occurring (36% and 21% respectively). HIV associated infections included C. neoformans, T. gondii, S. pneumoniae, N. meningitidis, VZV, HSV1 and HSV2. Overall mortality was 34%. Of the 36 patients who had a positive

microbiological diagnosis, mortality was 36% and moderate to severe disability at discharge was 22%. Conclusion: Meningitis and encephalitis are serious conditions affecting mainly young persons, and HIV infection is a significant risk factor. Further studies to demonstrate the role of viral pathogens, Enterococcus sp, S. viridans gp and CoNS are recommended