Carriage of ESBL- and AmpC-positive Enterobacteriaceae in the gastrointestinal tract of community subjects and hospitalized patients in the Czech Republic

Aim. The study aimed at analyzing ESBL- and AmpC-positive Enterobacteriaceae in the gastrointestinal tracts of university hospital inpatients and persons from the Olomouc Region community, and comparing the results with data from 2007. Methods. Bacteria were isolated from rectal swabs inoculated onto the ChromID (TM) ESBL selective medium (bioMerieux). Production of ESBL-type beta-lactamases was confirmed by the modified double-disk synergy test and AmpC enzyme production was detected by the AmpC disk test. ESBL-and AmpC-positive isolates were subjected to basic genetic analysis aimed at detecting the bla(TEM), bla(SHV), bla(CTX-M) and bla(AmpC) genes. Results. Over the study period (1 March 2010-1 May 2010), a total of 1,279 rectal swabs (70.4% of community subjects) were analyzed on the above medium. The prevalence rates of ESBL-positive Enterobacteriaceae were 8.2% in hospitalized patients and 3.2% in community subjects. Production of the AmpC enzyme was detected in 1.1% of bacterial isolates from the community and in one (0.3%) hospital isolate. Among ESBL, the most frequent genes encoding enzymes were from the CTX-M-1-like genes. Detected AmpC beta-lactamases belonged to the CIT, DHA and EBC groups. Conclusion. When compared with the year 2007, the rates of carriers of ESBL-positive bacteria increased in both hospitalized patients (from 3% to 8%) and community subjects (from 1% to 3%) in 2010. Given the fact that production of extended-spectrum beta-lactamases is clinically significant, knowing the epidemiological situation is very important for selecting adequate antibiotic therapy.