Prevalence of aminoglycoside modifying enzyme and 16S ribosomal RNA methylase genes among aminoglycoside-resistant Escherichia coli isolates

Aminoglycoside resistance determinants among 188 aminoglycoside-resistant blood culture Escherichia coli isolates from a tertiary hospital in Hong Kong, from 2004 to 2010 were investigated. Overall, 91% had aac(3)-II, 12.2% had aac(6′)-Ib/Ib-cr, and 5.4% had the methylase genes (rmtB, armA). Aminoglycoside-resistant isolates with aac(′)-Ib/Ib-cr, rmtB, and armA often had coresistance to multiple other antibiotics.