Huovinen S, Huovinen P, Torniainen K, Jacoby G A
Department of Medical Microbiology, University of Turku, Finland.
Eur J Clin Microbiol Infect Dis. 1988 Oct;7(5):651-5. doi: 10.1007/BF01964244.
The frequency of beta-lactam resistance was determined among 313 strains of Escherichia coli, 119 of Enterobacter/Klebsiella/Proteus spp., and 48 of Pseudomonas spp. isolated from blood cultures (at Turku University Central Hospital and Turku City Hospital) in 1983-1987. During this period the MIC50 of ampicillin for Escherichia coli increased from 8 to 32 micrograms/ml, the MIC90 of piperacillin from 16 to greater than 32 micrograms/ml and the MIC90 of cefuroxime from 4-8 to 16 micrograms/ml. Among 172 ampicillin-resistant isolates beta-lactamase-mediated resistance was characterized by DNA hybridization with TEM-1, SHV-1, OXA-1, OXA-2, PSE-1, PSE-2 and PSE-4 beta-lactamase probes and by isoelectric focusing. Beta-lactamase types found were TEM-1, TEM-2, SHV-1 and OXA-1. Isoelectric focusing did not show any other plasmid-mediated beta-lactamase varieties. Piperacillin-resistant strains showed mostly TEM-1 activity, but also produced OXA-1 and chromosomal beta-lactamase. Interestingly, a decrease in cefuroxime susceptibility in Escherichia coli occurred in a few OXA-1 producing strains as well as in strains that produced only chromosomal beta-lactamase. Two Escherichia coli strains that overproduced chromosomal beta-lactamase had increased ceftazidime MIC values (8-16 micrograms/ml).
1983年至1987年期间，在（于图尔库大学中心医院和图尔库市医院）从血培养物中分离出的313株大肠杆菌、119株肠杆菌/克雷伯菌/变形杆菌属细菌以及48株假单胞菌属细菌中，测定了β-内酰胺耐药性的频率。在此期间，大肠杆菌对氨苄西林的MIC50从8微克/毫升增至32微克/毫升，哌拉西林的MIC90从16微克/毫升增至大于32微克/毫升，头孢呋辛的MIC90从4 - 8微克/毫升增至16微克/毫升。在172株耐氨苄西林菌株中，通过与TEM-1、SHV-1、OXA-1、OXA-2、PSE-1、PSE-2和PSE-4β-内酰胺酶探针进行DNA杂交以及等电聚焦，对β-内酰胺酶介导的耐药性进行了表征。发现的β-内酰胺酶类型为TEM-1、TEM-2、SHV-1和OXA-1。等电聚焦未显示任何其他质粒介导的β-内酰胺酶变体。耐哌拉西林菌株大多表现出TEM-1活性，但也产生OXA-1和染色体β-内酰胺酶。有趣的是，在少数产生OXA-1的菌株以及仅产生染色体β-内酰胺酶的菌株中，大肠杆菌对头孢呋辛的敏感性有所下降。两株过度产生染色体β-内酰胺酶的大肠杆菌菌株的头孢他啶MIC值升高（8 - 16微克/毫升）。
