摘 要 克雷伯氏肺炎桿菌是一革蘭氏陰性具厚莢膜的腸內菌，可以引起肺炎、腦膜炎等疾病，此菌也是院內感染的重要致病菌之一。克雷伯氏肺炎桿菌的質體上常攜帶有超廣效性乙內醯胺酶的抗藥基因，因而具有抵抗第三代頭芽孢素如cefotaxime、ceftazidime和monobactam類如aztreonam等抗生素的能力。本實驗於1999年4月到8月之間共收集108株克雷伯氏肺炎桿菌。先以cefotaxime紙錠作為超廣效性乙內醯胺酶菌株的初步篩選，再用E-test和Double-disc test作確認，結果共有25株 (23.1﹪) 克雷伯氏肺炎桿菌帶有超廣效性乙內醯胺酶。經由PCR和等焦電泳的結果，發現25株菌中有22株帶TEM型的超廣效性乙內醯胺酶，有23株帶SHV型的超廣效性乙內醯胺酶，另外還有一株是非TEM和非SHV型的超廣效性乙內醯胺酶，這些菌株同時帶有多種不同pI值的乙內醯胺酶，pI值的範圍分布於5.4到8.4之間。利用RAPD和質體分型可得知25株帶有超廣效性乙內醯胺酶菌株間同源性並不高，無群突發之虞。DNA 定序的結果和PCR分型以及pI值有一定的相關性。綜合以上結果，我們認為本次台灣中部收集的克雷伯氏肺炎桿菌對超廣效性乙內醯胺酶有高的表現率，且抗藥性也不容忽視，值得進一步觀察克雷伯氏肺炎桿菌和其他菌株對超廣效性乙內醯胺酶的攜帶情形。; Abstract Klebsiella pneumoniae, a gram-negative enterobacterium, is one of the pathogens causing nosocomial infections. This organism can produce capsule and most of them show high resistance to antibiotics because of their harboring multiple drug-resistant plasmid. Detection of Klebsiella pneumoniae strains with extended-spectrum b-lactamases (ESBL)-related resistance phenotype and genotype is becoming important. A total of 108 preserved isolates of Klebsiella pneumoniae collected from April and August 1999 were found to be resistant to at least one of the third-generation cephalosporins using the routine disk diffusion method. Among these isolates, 25 (23.1﹪) isolates were classified as having an ESBL phenotype using the Double-disc test and E-test. The isolates each produced several b-lactamases with pI values ranging from 5.4-8.4. Plasmid and random amplified polymorphic DNA (RAPD) analysis revealed that all isolates harboring ESBLs were genetically unrelated. Clusters of isolates with the same PCR type were observed 22 isolates producing TEM-related type, 23 isolates producing SHV-related type, and one isolate producing non-SHV non-TEM ESBLs. The ESBL types determined by DNA sequencing were correlated with the results of PCR and isoelectric focusing (IEF). Our data show the prevalence and types of ESBLs and indicate that SHV and TEM β-lactamases were presence in the middle Taiwan area.
