Extended-spectrum β-lactamases in North America, 1987–2006

• Published in: Clinical microbiology and infection Vol. 14; pp. 134 - 143
• Main Author: Bush, K.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Elsevier Ltd 01.01.2008; Blackwell Publishing Ltd
• Subjects: Amino Acid Substitution; beta-Lactamases - biosynthesis; beta-Lactamases - classification; beta-Lactamases - genetics; Canada - epidemiology; Drug Resistance, Multiple, Bacterial - genetics; Enterobacteriaceae - classification; Enterobacteriaceae - drug effects; Enterobacteriaceae - enzymology; Enterobacteriaceae - genetics; Enterobacteriaceae Infections - epidemiology; Enterobacteriaceae Infections - microbiology; ESBL; Humans; North America - epidemiology; Population Surveillance - methods; review; United States - epidemiology; β-Lactamase; Canada; United States; North America; ESBL; review; β-Lactamase
• ISSN: 1198-743X; 1469-0691
• DOI: 10.1111/j.1469-0691.2007.01848.x

Extended-spectrum β-lactamases (ESBLs) derived from the TEM-1 β-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 β-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.