Comparison of CHROMagar Orientation Medium with Traditional Methods in Urinary Tract Infection Cultures.

BACKGROUND

Urinary tract infections (UTIs) are the most common infections in adults, and urine culture is the parameter that uses the most time and cost in microbiology laboratories. For this reason, the selection of fast and cost-effective methods in the evaluation of urine samples is one of the priority issues of microbiology laboratories. The aim of this study was to investigate the compatibility and cost-effectiveness of routinely used Blood Agar (BA), Eosin Methylene Blue (EMB) medium, and CHROMagar Orientation Medium (CO Medium) in the identification of microorganisms in urine samples.

METHODS

Consecutive urine samples (n: 700) sent to our laboratory were simultaneously inoculated onto BA/EMB media and CO medium. Urine samples were evaluated after 18 - 24 hours of incubation at 37℃ and the compatibility of the two methods was compared. The use of 104 Gram stains, 198 biochemical tests, and 9 identification kits was required with BA/EMB agar.

RESULTS

When 104 colonies with single growth were evaluated, presumptive identification with CO medium was found to be 100% compatible with the VITEK 2 system. The most isolated 62 Escherichia coli (E. coli) colonies gave dark pink-red color and were found to be fully compatible with the VITEK 2 system. Compatibility of BA and EMB medium evaluations with VITEK 2 system; E. coli (n: 62), KES group (n: 26), Pseudomonas spp. (n: 6) and Proteus spp. For (n: 2), it was determined as 69.3%, 57.69%, 100%, and 100%, respectively. According to the results of our study, when BA/EMB and CO Medium methods were compared, 182 Euro (€) savings were achieved in 700 urine cultures with CO Medium. It was estimated that the amount of savings could be 15,600 € per year.

CONCLUSIONS

CHROMagar Orientation Medium method can be used routinely with its advantages such as being cost-effective, reducing the workload, and not requiring additional operations. CHROMagar Orientation Medium can also be considered as an easily accessible method and opportunity that does not require infrastructure and trained personnel, especially for laboratories with low test capacity and having problems with the supply of com-mercial kits and automated systems.