Ampicillin and co-trimoxazole susceptibility of Shigella isolated in 1978-80

Shigella $1978{\sim}80$년 분리주의 Ampicillin 및 Co-trimoxazole 감수성

  • Chong, Yun-Sop (Departments of Clinical Pathology, Yonsei University College of Medicine) ;
  • Lee, Sam-Uel Y. (Departments of Clinical Pathology, Yonsei University College of Medicine) ;
  • Ryu, Young-Hat (Korea Health Development Institute)
  • 정윤섭 (연세대학교 의과대학 임상병리과) ;
  • 이삼열 (연세대학교 의과대학 임상병리과) ;
  • 유영해 (한국보건개발연구원)
  • Published : 1980.12.31

Abstract

Shigella remains to be an important enteric pathogen in this country for the moment. Moreover, since 1978, most of the isolates have become resistant to ampicillin and co-trimoxazole, which used to be the drugs of choice for shigellosis. Since a disc diffusion technique alone has been used in our routine susceptibility test, the minimum inhibitory concentrations(MIC) of both ampicillin and co-trimoxazole to Shigella have never been known. In order to determine these, 195 isolates were tested by an agar dilution method, all of which were isolated at Yonsei Medical Center during the period of June 1978 to July 1980. The following results were obtained. 1. Sixty cultures(29.7%) were susceptible to ampicillin, being the MIC of 8 ${\mu}g/ml$ or less and 53(27.2%) were susceptible to co-trimoxazole, being the MIC of TMP/SMZ 4/76 ${\mu}g/ml$ or less. S. flexneri type 2 was often resistant to both antimicrobic agents. 2. An increasing rate of resistant isolates was noted, particularly in the year of 1979. 3. Many isolates were resistant to both agents. Somewhat more cultures. were ampicillin susceptible and co-trimoxazole resistant than the other way around. It seems that the determination of species or even serotypes might be of help sometimes to select proper antimicrobic agent to control the infection. A routine antimicrobic susceptibility test of Shigella to both ampicillin and co-trimoxazole would be advisable for a better selection of chemotherapeutic agent.

Keywords