Surveillance of pneumococcal meningitis among children in Sindh, southern Pakistan.

BACKGROUND: Information about the burden of invasive pneumococcal disease among children in Pakistan is limited. METHODS: Surveillance of bacterial meningitis among children aged <5 years was set up at 18 hospitals in southern Pakistan that fulfilled the following criteria: (1) >30 pediatric admissions weekly, (2) skilled personnel to perform lumbar punctures, and (3) close proximity to an Aga Khan University Hospital laboratory collection point. RESULTS: A total of 2690 children were admitted to the hospital with suspected acute bacterial meningitis, and 2646 (98%) underwent lumbar puncture. Of the 2646 cerebrospinal fluid specimens obtained, 412 (16%) were purulent, and pathogens were detected by culture or latex agglutination testing in 83 (20.1%) of the purulent specimens. Of the 83 isolates detected, 48 (57.8%) were Haemophilus influenzae type b, 32 (38.5%) were Streptococcus pneumoniae, and 3 (3.6%) were Neisseria meningiditis. Overall, 81% of the pathogens detected were from children aged <1 year. More than 50% of families reported definite prior antimicrobial use. The minimum detected incidence rates of purulent meningitis in Hyderabad were 112 cases per 100,000 children aged <1 year and 45.3 cases per 100,000 children aged <5 years. After adjustment for limitations in access to care and the low sensitivity of cerebrospinal fluid culture, the adjusted incidence rates of pneumococcal meningitis were 81 cases per 100,000 children aged <1 year (95% confidence interval, 26.2-190.5 cases per 100,000) and 20 cases per 100,000 children aged <5 years (95% confidence interval, 7.3-43.7 cases per 100,000). Of the 32 children with pneumococcal meningitis, 8 (25%) died during hospitalization. CONCLUSIONS: Our surveillance system detected a substantial burden of purulent meningitis among infants and children in southern Pakistan. H. influenzae type b and S. pneumoniae accounted for >90% of detected pathogens. The use of vaccines against these 2 pathogens could prevent a substantial portion of disease and deaths in Pakistan.

Enhanced diagnosis of pneumococcal meningitis with use of the Binax NOW immunochromatographic test of Streptococcus pneumoniae antigen: a multisite study.

BACKGROUND: Accurate etiological diagnosis of meningitis in developing countries is needed, to improve clinical care and to optimize disease-prevention strategies. Cerebrospinal fluid (CSF) culture and latex agglutination testing are currently the standard diagnostic methods but lack sensitivity. METHODS: We prospectively assessed the utility of an immunochromatographic test (ICT) of pneumococcal antigen (NOW Streptococcus pneumoniae Antigen Test; Binax), compared with culture, in 5 countries that are conducting bacterial meningitis surveillance in Africa and Asia. Most CSF samples were collected from patients aged 1-59 months. RESULTS: A total of 1173 CSF samples from suspected meningitis cases were included. The ICT results were positive for 68 (99%) of the 69 culture-confirmed pneumococcal meningitis cases and negative for 124 (99%) of 125 culture-confirmed bacterial meningitis cases caused by other pathogens. By use of culture and latex agglutination testing alone, pneumococci were detected in samples from 7.4% of patients in Asia and 15.6% in Africa. The ICT increased pneumococcal detection, resulting in similar identification rates across sites, ranging from 16.2% in Nigeria to 20% in Bangladesh. ICT detection in specimens from culture-negative cases varied according to region (8.5% in Africa vs. 18.8% in Asia; P< .001), prior antibiotic use (24.2% with prior antibiotic use vs. 12.2% without; P< .001), and WBC count (9.0% for WBC count of 10-99 cells/mL, 22.1% for 100-999 cells/mL, and 25.4% for >or=1000 cells/mL; P< .001 by test for trend). CONCLUSIONS: The ICT provided substantial benefit over the latex agglutination test and culture at Asian sites but not at African sites. With the addition of the ICT, the proportion of meningitis cases attributable to pneumococci was determined to be similar in Asia and Africa. These results suggest that previous studies have underestimated the proportion of pediatric bacterial meningitis cases caused by pneumococci.