[Changes over 10 years of ampicillin-resistant Haemophilus influenzae isolated from children].
We examined the frequency of ampicillin (ABPC) resistance of 3784 strains of Haemophilus influenzae isolated from the infants aged from 1 month after birth to 12 years who had been treated in the Pediatric Department of our hospital for 9 years and 6 months from July 1999 to December 2008. We determined the drug susceptibility by Etest, and judged the resistance by the standard of Clinical and Laboratory Standard Institute. The rate of strains of MIC of less than 2 microg/ml to ABPC was 87.1% in 1999, but the ratio was decreasing year after year significantly up to 28.7% in 2008 (p < 0.001). beta-lactamase negative ABPC resistant (BLNAR) strains whose MIC to ABPC was more than 4 microg/ml was 2.9% in 1999, but increased significantly to 43.3% in 2008 (p < 0.001). MIC90 was 2 microg/ml in 1999, but increased to 16 microg/ml in 2008.
Department of Pediatrics, Asahikawa Kosei Hospital.
Hiroshi
H
Sakata
D000667:Ampicillin / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D004305:Dose-Response Relationship, Drug; D024881:Drug Resistance, Bacterial; D006193:Haemophilus influenzae / Q000187:drug effects* / Q000302:isolation & purification*; D006748:Hospital Departments / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007564:Japan; D008826:Microbial Sensitivity Tests; D010372:Pediatrics; D013997:Time Factors
D000900:Anti-Bacterial Agents; D000667:Ampicillin