Nosocomial urinary tract infections caused by extended-spectrum beta-lactamases producing Enterobacteriaceae in Latvia

Abstract number: p678

Paberza  R., Chumak  T., Zilevica  A., Selderina  S., Luzbinska  L., Storozenko  J., Rozentale  B.


To discover tests for screening and confirmation of extended-spectrum b-lactamases (ESBLs) production in different genera of the family Enterobacteriaceae. To evaluate ESBL producing strains isolated from hospital patients with urinary tract infections (UTI) in Latvia.


316 non-duplicate Enterobacteriaceae strains collected from urine UTI patients from Infectology Center of Latvia and children hospital "Gailezers" during January 2004 to October 2005 and two quality control strains were tested. Identification was performed in mini API system, for susceptibility testing – disk diffusion, E-test and ATB mini API were used. Screening of ESBL positive strains was obtained in mini API ATB Expert system. ESBL production was confirmed by disk diffusion (NCCLS, 2002) and E-test ESBL: both cefotaxime/cefotaxime + clavulanic acid and ceftazidime/ceftazidime + clavulanic acid (AB Biodisk, 2000).


The screening of ESBL producing strains revealed 12.0% positive Enterobacteriaceae (38 of 316): among isolated Klebsiella spp. 27.5% (11 from 40 strains), Escherichia coli 6.9% (15 of 218), Enterobacter spp. 31.5% (5 of 16), Proteus spp. 37.5% (6 of 16), Morganella morganii 11.1% (1 of 9). There were not ESBL producing strains in two Serratia spp. and five Citrobacter spp. strains in screening. The confirmatory tests occurred to be positive in all E. coli and Klebsiella strains, identified as resistant phenotype ESBL, five of six Proteus mirabilis strains, marked as resistant phenotype ESBL. In Enterobacter species only two of five, marked in screening as ESBL possible by Expert, were ESBL positive by confirmatory tests. As concerns one M. morganii ESBL suspicious strain was not confirmed.


Mini API ATB Expert system should bee recommended: as screening for ESBL production in Enterobacteriaceae strains, especially Klebsiella species, E. coli and P. mirabilis. ESBL screening marked as ESBL possible must be confirmed with confirmatory tests by discs and E-test ESBL.

Session Details

Date: 01/08/2007
Time: 00:00-00:00
Session name: XXIst ISTH Congress
Location: Oxford, UK
Presentation type:
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