耳漏と鼻汁から検出されたインフルエンザ菌および肺炎球菌の薬剤耐性の変化

抄録

The recent increase in resistance to the major antibiotics has required us to reevaluate antibiotictherapy in ear and nasal infections, which are caused mainly by Haemophilus influenzae, Streptococcuspneumoniae and Moraxella catarrharis. The MICs of antibiotics against the first two bacteriawere determined at the time of treatment of ear and nasal infection in 1991, 1996 and 1999and the findings were compared. The MIC, which is a measure of in vitro susceptibility, is theconcentration that inhibits 90% of a collection of isolates. Between 10-15% of H. influenzae areampicillin-resistant. In1996,β-lactamase-negative ampicillin resistant H.influenzae(BLNAR)wasisolated from nasal discharge and increased almost to the same level as BLNAR. In 2000, BLNARaccounts for more than 20% of H. influen,zae. We consider that CTRX given by intravenous administrationand CDTR by oral administration are effective against 80% of H. influenzae based ontheir MICs. Against S. pneumoniae, the rates of PSSP, PISP and PRSP efficacy in 1991 were 75.6%,22.2% and 2.2%, respectively. In 1996, these values were 55.6%, 38.8% and 5.6%. In 1999, theywere 24.2% and 56.4% and 19.4%, respectively. In 1996, PAPM/BP was effective against 100% ofS. pneumonide at the MIC dosage of 0,06μg/ml, whereas in 1999, it was effective against 87% ofthe strains. Seventy-five percent of children from whom infection-resistant S. pneumoniae wereisolated had been administered several antibiotics prior to treatment in our hospital. We considerthat the sensitivity will decrease further in the future, thereby making treatment of the infectiontherapy more difficult.