Evaluation of CPS ID2 medium for detection of urinary tract bacterial isolates in specimens from a rehabilitation center

Abstract

CPS ID2 medium (bioMérieux) enables the presumptive identification of Escherichia coli and enterococci as well as the detection of indologenous or nonindologenous Proteeae and bacteria belonging to the Klebsiella, Enterobacter, and Serratia group with a specificity ranging from 98 to 100%. When the cultures were polymicrobial, the sensitivity varied from 70 to 97%, and the sensitivity varied from 97 to 100% when they were monomicrobial.

Evaluation of BBL CHROMagar orientation medium for detection and presumptive identification of urinary tract pathogens

“…The present investigation shows that the quantitative recovery of bacterial growth on the two chromogenic media corresponded well to that in previous studies (18,19,(21)(22)(23)27). The total number of organisms recovered was higher on both chromogenic media than on blood agar and MacConkey agar without crystal violet ( Table 2).…”

“…The production of ␤-glucuronidase, which is used to identify E. coli on CPS ID2 medium, has been evaluated in many studies (5-8, 10, 11, 13-16) and about 95 to 98% of E. coli isolates are reported to produce this enzyme (18,19,22,23,27), while we found that only 91.3% of the E. coli isolates were positive. BBL CHROMagar Orientation medium, which contains a chromogenic substrate for the detection of an enzyme of lactose metabolism, stained all but one (99.6%) of the E. coli strains in the expected color.…”

“…Media with chromogens, on which the colonies rather than the surrounding medium is stained, easily allow for the detection of the target organisms even in mixed cultures and at low colony counts (17). However, most of the studies performed with these media did not investigate the recovery of rarer organisms (15,(18)(19)(20)(21)(22)(23).…”

“…The use of chromogenic medium formulations offers a time-saving method for the reliable detection, enumeration, and presumptive identification of urinary tract pathogens. One of the greatest advantages of these media is the easy recognition of mixed cultures.For several years chromogenic media that allow for the direct identification of the most frequently isolated bacterial and fungal species, such as CPS ID2, SMID agar, and Albicans ID (BioMérieux), Rambach agar (CHROMagar), and BBL CHROMagar Candida (Becton Dickinson), have been available for use with either urine samples or stool specimens or for the identification of yeasts (1,2,9,12,19,22,(24)(25)(26).Since the diagnosis of urinary tract infections contributes significantly to the daily workload in a microbiology laboratory, any innovation that tends to reduce the workload is always welcome when a high-quality standard is still maintained.Our objectives were to evaluate the accuracy of BBL CHROMagar Orientation medium and CPS ID2 agar compared to those of conventional media (Columbia agar with 5% sheep blood and MacConkey agar without crystal violet) for the detection and enumeration of the organisms commonly involved in urinary tract infections and to compare the ability of both chromogenic media to correctly identify the more frequently occurring organisms or organism groups with only a minimum of confirmatory tests.Apart from specimens with clinically significant organism counts (Ն10 5 CFU/ml), we included specimens with Ͻ10 5 CFU/ml in order to evaluate the sensitivity of the media.…”

“…For several years chromogenic media that allow for the direct identification of the most frequently isolated bacterial and fungal species, such as CPS ID2, SMID agar, and Albicans ID (BioMérieux), Rambach agar (CHROMagar), and BBL CHROMagar Candida (Becton Dickinson), have been available for use with either urine samples or stool specimens or for the identification of yeasts (1,2,9,12,19,22,(24)(25)(26).…”