Childhood bacterial meningitis beyond the neonatal period in southern Nigeria: changes in organisms/antibiotic susceptibility.

Of 253 culture proven cases of bacterial meningitis in infants aged over a month and children up to one year old in Benin City, Nigeria, from 1985-1990, 49.8% were due to N. meningitidis, 21.4% S. pneumoniae, 15.4% H. influenzae and 13.4% other organisms, including S. aureus and enterobacteriaceae. Compared to the period 1974-1984 in Southern Nigeria, N. meningitidis has replaced S. pneumoniae as the commonest organism. N. meningitidis was relatively infrequent below two years of age while H. influenzae was rare after five years. Approximately half of isolates of S. aureus and enterobacteriaceae were in infants aged six months or less. The proportions of sensitive strains of three common organisms to three commonly used drugs were chloramphenicol (95.3%) > ampicillin (83.9%) > penicillin (67.6%). Resistance to penicillin has increased while simultaneous resistance to ampicillin and chloramphenicol has emerged as a new problem among the three common bacteria. It is concluded that although the combination of ampicillin and chloramphenicol is still reasonable for initial "blind" therapy of meningitis, the emergence of multiple drug resistance suggests the need for consideration of a revision of current practice. The third generation cephalosporins are suggested as a suitable alternative.