Etiologic spectrum and pattern of antimicrobial drug susceptibility in bacterial meningitis in Sokoto, Nigeria

Etiologic agents of meningitis were prospectively investigated among patients admitted to Usman Danfodio University Teaching Hospital, Sokoto. Of 1097 cerebrospinal fluid (CSF) samples submitted to the microbiology laboratory from various wards of the hospital, 289 (26%) were microscopically, culturally and/or serologically proven to be bacterial meningitis. The etiologic spectrum was as follows: Neisseria meningitidis (61%), Streptococcus pneumoniae (18%), Haemophilus influenzae (10%), Staphylococcus aureus (6%), Coliform bacilli (3%), Escherichia coli (0.7%), Mycobacterium tuberculosis (0.7%), Listeria monocytogenes (0.4%), Flavobacterium meningosepticum (0.4%) and Pseudomonas putrifasciens (0.4%). Bacterial meningitis was most prevalent (195 or 68%) among children aged 1-9 y, while adults and neonates were least affected. Coliform bacilli caused five of right neonatal cases. Males were more frequently affected than females (chi(2) = 12.50; p < 0.05). Culture and microscopy were comparatively less efficient than the search for bacterial antigens, especially in the diagnosis of Haemophilus tis. Antimicrobial susceptibility of N. meningitidis to ampicillin and benzyl penicillin reduced progressively over the years (F = 406.98; p < 0.001). Nineteen (11%) of the isolates (5 Meningococci, 7 Staph. aureus, 1 Haem. influenza and 6 others) showed simultaneous resistance to chloramphenicol, ampicillin and benzyl penicillin.