Isolation and drug resistance of pathogenic bacteria from Gunma prefecture in 1994 Gunma Study Group on Information about Identified Pathogenic Microbes

• Published in: Japanese Journal of Chemotherapy Vol. 44; no. 8; pp. 626 - 632
• Main Authors: Iyobe, Sizuko, Okubo, Toyoji, Yomoda, Sachie, Kobayashi, Isao, Tsunoda, Mitsuko, Furukawa, Michiyo, Takahashi, Ayako
• Format: Journal Article
• Language: Japanese
• Published: Japanese Society of Chemotherapy 25.08.1996
• ISSN: 1340-7007; 1884-5886
• DOI: 10.11250/chemotherapy1995.44.626

On a survey of 1, 794 bacterial isolates from nine hospitals in Gnnma prefecture in the school year of 1994, we determined the frequency of isolation species and their sensitivity 14 chemotherapeutic agents, especially forcussing on methicillin-resistant Staphylococcus aureus (MRSA) and penicillin-resistant Streptococcus pneumoniae strains. The results were compared with the data obtained during the past five years. 1.The bacterial species isolated at high frequencies were S. aureus (22.3%), Pseudomonas aeruginosa (11.8%), coagulase-negative Staphylococci (CNS)(8.4%), Escherichia coli (6.4%), Haemophilus influenzae (5.4%), and Enterococcus faecalis (5.4%), in order of the isolation frequency. The frequency of isolation of H. influenzae from outpatients and of S. aureus from inpatients was increased by 3% and 5%, respectively, when compared with those in 1993, but no annual changes was observed in other species. 2.Of S. aureus, more than 75% of the MRSA strains were resistant to multiple agents such as penicillins, cephems, aminoglycosides, macrolides, tetracyclines, and new-quinolones, while less than 15% of the methicillin-sensitive S. aureus strains were resistant to these multiple agents except penicillins and none of them were resistant to vancomycin. 3.MRSA strains were isolated at high frequency from special internal medicine wards in larger hospitals with a large number of beds. 4.For S. pneumoniae, the breaking point dividing the sensitive and resistant strains was clearly determined at 6.25μg/ml for cefaclor but was not obvious for benzylpenicillin, ampicillin (ABPC) and piperacillin (PIPC). Penicillin-resistant S. pneumoniae strains were identified by using one-concentration disks for the strains with inhibition zones with diameters less than 30mm, 32 mm, and 29 mm, respectively against benzylpenicillin, ABPC, and PIPC.