DOI: http://dx.doi.org/10.18203/2320-6012.ijrms20173584

Comparative evaluation of different culture media for the isolation and identification of common urinary pathogens

Aarti Chaturvedi, Ritu Garg, Varsha A. Singh

Abstract


Background: Urinary tracts infections (UTIs) are one of the most common infections encountered in hospital as well as community settings. There is continuous increase in incidence of this infection leading to more consumption of antimicrobial drugs. Urine cultures occupy most of the workload of routine microbiology laboratories in developing country like India. Accurate and rapid identification of pathogens is the primary responsibility of a clinical microbiology laboratory.

Methods: Mid-stream urine and catheterized samples were collected. Cultures were plated on blood agar, MacConkey agar and cysteine lactose electrolyte deficient media and incubated overnight at 35°C-37°C in ambient air. Colonies on the MacConkey agar, CLED agar and blood agar were also identified. The final identification of the isolates was done using standard identification protocol.  Antimicrobial susceptibility was performed by Kirby- Bauer disc diffusion test according to the CLSI guidelines.

Results: Out of 500 urine samples processed, 211 samples showed significant growth, 24 samples showed polymicrobial growth and 265 samples were reported sterile.  Out of these 211, 199 showed pure growth and 12 showed mixed growths. Out of 199 pure growths, 126 were gram negative bacilli, 56 were gram positive cocci and 17 were yeast. All the gram-negative bacilli grown on all the media but most of the gram-positive cocci and yeast were unable to grow on Mac-Conkey agar and blood agar but grew successfully on CLED agar.

Conclusions: So, in resource constrain laboratories, CLED agar can be used as media of choice for isolation of common uropathogens because it is user friendly, cost effective and decreases work load of the laboratories.


Keywords


CLED agar, Urine samples, Urinary tract infections

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References


Mohan B, Gupta P, Appannanavar SB, Singh G, Taneja N. Evaluation of new chromogenic media for identification of uropathogens from complicated urinary tract infections in a tertiary healthcare setting. Int J Med Microbiol. 2015;33(1):183-4.

Jain S, Sharma M, Kumar M, Shree N, Sharma Y. Prevalence of uropathogens in urinary tract infection and their antimicrobial resistance pattern in a North Delhi hospital, India: A nine-years study. 2014;6(1):545-52.

Akmal Hasan SK, Naveen Kumar T, Radha Kishan N, Neetha K. Laboratory diagnosis of urinary tract infections using diagnostics tests in adult patients. Int J Res Med Sci. 2014;2(2):415-21.

Fung JC, Lucia B, Clark E, Berman M, Goldstein J, D'Amato RF. Primary culture media for routine urine processing. J Clin Microbiol. 1982;16:632-6.

Wong WT, Lee KH. A trial of cysteine-lactose-electrolyte deficient medium for Urinary bacteriology. The bulletin of the Hong Kong Medical Association. 1970;22:89-91.

Qaiser S, Zeeshan M, Jabeen K, Ahsan T, Zafar A. Comparison of chromogenic urinary tract infection medium with cysteine lactose electrolyte deficient media in a resource limited setting. J Pak Med Assoc. 2011;61(7):632-5.

Collee JG, Miles RS, Watt B. Tests for the identification of bacteria. In: Collee JG, Fraser AG, Marmion BP, Simmons A, eds. Mackie and MacCartney practical medical microbiology, 14th ed. Edinburgh: Churchill Livingstone; 1996:151-79.

Ananthanarayan R, Jayaram Paniker CK. Urinary tract infections. In: Kapil A, eds. Text Book of Microbiology. 9th ed. Hyderabad, India: University Press; 2013:671.

Sastry AS, Bhat SK. Clinical microbiology (infective syndrome). In: Essentials of Medical Microbiology. 1st ed. JAYPEE Publications. 2016:585-588.

CLSI. Performance standards for antimicrobial susceptibility testing; 24th Informational Supplement. CLSI Document M100-S24, Wayne PA: Clinical and Laboratory Standards Institute; 2014. Available at http://www.gxccl.com/download/upload/CLSIM100-S24%E8%8B%B1%E6%96%87%E7%89%88.pdf.

Manjusree BS, Sasikumari O, Bai JTR. A study on evaluation of different culture media for the isolation of routine urinary pathogens. Int J Curr Microbiol App Sci. 2017;6(2):195-201.

Sharmin, S, Alamgir F, Begum F, Jaigirdar Q. Use of chromogenic agar media for identification of uropathogen. Bangladesh J Med Microbiol. 2010;4:18-23.

Singh VP, Mehta A. Bacteriological profile of urinary tract infections at a tertiary care hospital in Western Uttar Pradesh, India. Int J Res Med Sci. 2017;5(5):2126-9.

Gupta V, Yadav A, Joshi RM. Antibiotic resistance pattern in uropathogens. Ind J Med Microbiol. 2002;20(2):96-8.

Ciragil P, Gul M, Aral M, Ekerbicer H. Evaluation of a new chromogenic medium for isolation and identify cation of common urinary tract pathogens. Eur J Clin Microbiol Infect Dis. 2006;25:108-11.