Prevalence of β-lactamase-negative ampicillin-resistant haemophilus influenzae isolated from patients of a teaching hospital in Thailand.

The aim of this study was to investigate the prevalence of β-lactamase-negative ampicillin-resistant (BLNAR) Haemophilus influenzae isolated from patients of a teaching hospital in Thailand. Eighty-eight isolates of H. influenzae were collected between September 2005 and March 2008.

CMY-2, CMY-8b, and DHA-1 plasmid-mediated AmpC β-lactamases among clinical isolates of Escherichia coli and Klebsiella pneumoniae from a university hospital, Thailand.

Between February 2005 and January 2006 in Srinagarind Hospital, Thailand, 44 from 1730 isolates (2.5%) of Escherichia coli and 8 from 982 isolates (0.8%) of Klebsiella pneumoniae were found to produce plasmid-mediated AmpC β-lactamases (pAmpCs) as detected by a cefoxitin-Hodge test followed by a multiplex polymerase chain reaction (PCR) technique.