[Chromogenic medium for detection of enterobacteria producing beta-lactamases in North-Eastern Romania].
We evaluated the performances and analyzed practicability of an ESBL-detecting chromogenic agar medium (chromID ESBL, bioMerieux) for the screening of ESBL production.


METHODS
We have tested 112 enterobacteria strains, isolated in 2009 year, in North Eastern region of Romania. Each bacterial strain was cultured on a prepared plate chromogenic medium and the results were recorded after incubation at 37 degrees C for 18 to 24 h or, if necessary, for 48 h. We calculated the sensitivities, specificities, and positive and negative predictive values for this medium, using as gold standard ceftzidime or cefotaxime and clavulanate combination disks on Iso-Sensitest agar. K. pneumoniae ATCC 700603 and E. coli ATCC 25922 were used as the positive and negative control for ESBL production, respectively.


RESULTS
For all tested strains, the chromID ESBL agar showed a high sensitivity (97%), but a low specificity (66%). The positive and negative predictive values were 98% and 57%, respectively. The chromID ESBL had false-positive results for 2 confirmed ESBL-positive strains.


CONCLUSIONS
The very good sensitivity of the chromID ESBL agar ESBL detection represent a convenient method for the recovery and identification of ESBL-producing enterobacteria.
Tuchiluş
Cristina
C
Universitatea de Medicină şi Farmacie Gr.T. Popa Iaşi, Facultatea de Medicină, Disciplina de Microbiologie.
Poiată
Antonia
A
Buiuc
D
D
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001431:Bacteriological Techniques; D002439:Cefotaxime / Q000494:pharmacology; D002863:Chromogenic Compounds / Q000378:metabolism*; D019818:Clavulanic Acid / Q000494:pharmacology; D003470:Culture Media; D004755:Enterobacteriaceae / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D004756:Enterobacteriaceae Infections / Q000382:microbiology*; D004926:Escherichia coli / Q000201:enzymology; D007711:Klebsiella pneumoniae / Q000201:enzymology; D011237:Predictive Value of Tests; D012383:Romania; D013997:Time Factors; D018440:beta-Lactam Resistance / Q000235:genetics; D001618:beta-Lactamases / Q000096:biosynthesis* / Q000235:genetics
D000900:Anti-Bacterial Agents; D002863:Chromogenic Compounds; D003470:Culture Media; D019818:Clavulanic Acid; D001618:beta-Lactamases; D002439:Cefotaxime