Extended-spectrum beta-lactamases in North America, 1987-2006.
Extended-spectrum beta-lactamases (ESBLs) derived from the TEM-1 beta-lactamase were first identified in the USA in outbreak strains of Klebsiella pneumoniae in the middle to late 1980s, together with the SHV-5 ESBL. The TEM-10, TEM-12 and TEM-26 enzymes have remained in US hospitals, but have been joined by other ESBLs that are variants of the SHV-1 broad-spectrum beta-lactamase. In the most recent surveys from hospitals in the eastern part of the USA, the most prominent ESBLs have been the SHV-7 and SHV-12 enzymes. In Canada, a wider variety of ESBLs has been identified, with multiple members of the TEM, SHV and CTX-M classes being represented in surveillance isolates. SHV-type and CTX-M ESBLs have appeared in many Canadian isolates, with an outbreak of CTX-M-14-related enzymes from Calgary, but limited TEM-derived ESBLs. Surprisingly, few CTX-M ESBLs have yet been reported in the USA, in contrast to the rest of the world, where the CTX-M enzymes have become a predominant ESBL family.
D019943:Amino Acid Substitution; D002170:Canada / Q000453:epidemiology; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D004755:Enterobacteriaceae / Q000145:classification / Q000187:drug effects* / Q000201:enzymology* / Q000235:genetics; D004756:Enterobacteriaceae Infections / Q000453:epidemiology* / Q000382:microbiology; D006801:Humans; D009656:North America / Q000453:epidemiology; D011159:Population Surveillance / Q000379:methods; D014481:United States / Q000453:epidemiology; D001618:beta-Lactamases / Q000096:biosynthesis* / Q000145:classification / Q000235:genetics
D001618:beta-Lactamases