Drug Resistance and Distribution of R Plasmids in Escherichia coli Isolated in Pediatric Patients.

Chang, I S; Yoon, Y S; Kim, K B; Lee, H C

Original Article

Journal of the Korean Pediatric Society 1979;22(9):755-764.
Published online September 15, 1979.

Drug Resistance and Distribution of R Plasmids in Escherichia coli Isolated in Pediatric Patients.

I S Chang¹, Y S Yoon¹, K B Kim¹, H C Lee²

¹Dept. of Pediatrics, Kwang-Ju Christian Hospital, Korea.
²Dept. of Microbiology, Chonnam University Medical School, Korea.

新生兒 및 小兒科患者에서 分離한 大腸菌의 藥劑耐性 및 R因子

張仁淑^¹^, 尹英秀^¹^, 金基福^¹^, 李炫哲^²

^¹光州基督病院小兒科
^²全南醫大細菌學敎室

Abstract

One hundred seventy strains of E.coli were isolated from meconium and stool samples of newborn infants delivered in KCH, pediatric inpatients, and outpatients during 1978. Strain resistance to antimicrobial agents, and distribution of R Plasmids among them were tested. No. coliform bacterium was detected in meconium samples within 6 hours of birth, but after 20 hours all meconium samples contained E.coli. Of 170 strains isolated, 104(61.4%) were resistant to one or more of the drugs tested, and 88.5% of these resistant strains were resistant to multiple drugs. Strains resistant to four or more drugs were significantly more prevalent in isolates from older inpatients than in those from newborn infants, and outpatients. Resistance was found most frequently to tetracyclin (TC:57.6%), follwed by streptomycin (SM:52.9%), doxycycline(DC:46.5%), chloramphenicol(CM:42.9%), ampicillin(AP:37.1%), Kanamycin(KM:27.1%), gentamicin(GM:19.4%), and nalidixic acid(NA:2.4%). The prevalence of resistant strains was significantly higher in the group of inpatients than in the groups of newborn infants and outpatients. Of these 104 resistant strains, 51 strains(49.0%) carried R Plasmids that were transferable by the usual mixed cultivation. The transfer frequency of AP and KM resistance was much higher than that of CM, TC and SM resistance. The greater the multiplicity of resistance, the greater was the likelihood that part or all of the resistance markers would be transferred. Of 15 different kinds of R Plasmids such as (AP)r, (TC)r, (CM)r, (KM)r, (SM)r, (AP,CM)r, (AP,KM)r, (AP,TC)r, (AP,TC,CM)r, (AP,CM,KM)r, (AP,CM,SM,TC)r, (AP,CM,SM,KM)r, and (AP,CM,SM,KM,TC)r , the most frequent pattern was (AP)r.