[An adult case of bacterial meningitis caused by penicillin-resistant Streptococcus pneumoniae with gene mutations of penicillin binding proteins].

A 62-year-old Japanese male developed acute bacterial meningitis. Administration of ABPC, CDZM, INH, and RFP was started. The causative bacteria was identified as penicillin-resistant Streptococcus pneumoniae (PRSP) 3 days later. We changed ABPC to PAPM/BP and the bacterial meningitis improved dramatically. Measurement of minimum inhibitory concentration (MIC) of the bacterial strain from CSF and blood showed that it is susceptible to PAPM/BP and RFP. Mechanism of drug resistance is considered to be gene mutations of penicillin binding protein (PBP) that decreases drug affinity to PBP. Recently penicillin resistance of Streptococcus pneumoniae has been found to be associated with mutations of pbp-2b, 1a genes and the cefem resistance of that is with those of pbp-2x, and 1a genes. By PCR (polymerase chain reaction) analysis we identified the mutations of pbp-1a, 2x, and 2b genes of the isolated strain of Streptococcus pneumoniae. We emphasize the importance of detection of pbp gene mutations for the diagnosis of PRSP infections.