Causes of Pediatric Meningitis in Botswana: Results From a 16-Year National Meningitis Audit.

BACKGROUND: Central nervous system infections are an important cause of childhood morbidity and mortality in high HIV-prevalence settings of Africa. We evaluated the epidemiology of pediatric meningitis in Botswana during the rollout of antiretroviral therapy, pneumococcal conjugate vaccine and Haemophilus influenzae type B (HiB) vaccine. METHODS: We performed a cross-sectional study of children (<15 years old) evaluated for meningitis by cerebrospinal fluid (CSF) examination from 2000 to 2015, with complete national records for 2013-2014. Clinical and laboratory characteristics of microbiologically confirmed and culture-negative meningitis were described and incidence of Streptococcus pneumoniae, H. influenzae and cryptococcal meningitis was estimated for 2013-2014. RESULTS: A total of 6796 unique cases were identified. Median age was 1 year [interquartile range 0-3]; 10.4% (435/4186) of children with available HIV-related records were known HIV-infected. Overall, 30.4% (2067/6796) had abnormal CSF findings (positive microbiologic testing or CSF pleocytosis). Ten percent (651/6796) had a confirmed microbiologic diagnosis; including 26.9% (175/651) Cryptococcus, 18.9% (123/651) S. pneumoniae, 20.3% (132/651) H. influenzae and 1.1% (7/651) Mycobacterium tuberculosis. During 2013-2014, national cryptococcal meningitis incidence was 1.3 cases per 100,000 person-years (95% confidence interval, 0.8-2.1) and pneumococcal meningitis incidence 0.7 per 100,000 person-years (95% confidence interval, 0.3-1.3), with no HiB meningitis diagnosed. CONCLUSIONS: Following HiB vaccination, a marked decline in microbiologically confirmed cases of H. influenzae meningitis occurred. Cryptococcal meningitis remains the most common confirmed etiology, demonstrating gaps in prevention-of-mother-to-child transmission and early HIV diagnosis. The high proportion of abnormal CSF samples with no microbiologic diagnosis highlights limitation in available diagnostics.

Epidemiology of adult meningitis during antiretroviral therapy scale-up in southern Africa: Results from the Botswana national meningitis survey.

OBJECTIVES: Data on meningitis epidemiology in high HIV-prevalence African settings following antiretroviral therapy scale-up are lacking. We described epidemiology of adult meningitis in Botswana over a 16-year period. METHODS: Laboratory records for adults undergoing lumbar puncture (LP) 2000-2015 were collected, with complete national data 2013-2014. Cerebrospinal fluid (CSF) findings and linked HIV-data were described, and national incidence figures estimated for 2013-2014. Temporal trends in meningitis were evaluated. RESULTS: Of 21,560 adults evaluated, 41% (8759/21,560) had abnormal CSF findings with positive microbiological testing and/or pleocytosis; 43% (3755/8759) of these had no confirmed microbiological diagnosis. Of the 5004 microbiologically-confirmed meningitis cases, 89% (4432/5004) were cryptococcal (CM) and 8% (382/5004) pneumococcal (PM). Seventy-three percent (9525/13,033) of individuals undergoing LP with identifiers for HIV registry linkage had documented HIV-infection. Incidence of LP for meningitis evaluation in Botswana 2013-2014 was 142.6/100,000 person-years (95%CI:138.3-147.1); incidence of CM was 25.0/100,000 (95%CI:23.2-26.9), and incidence of PM was 2.7/100,000 (95%CI:2.4-3.1). In contrast to previously reported declines in CM incidence with ART roll-out, no significant temporal decline in pneumococcal or culture-negative meningitis was observed. CONCLUSIONS: CM remained the predominant identified aetiology of meningitis despite ART scale-up. A high proportion of cases had abnormal CSF with negative microbiological evaluation.