Optimising Urinary Pathogen Detection: A Cross-sectional Comparative Study of CLED Agar, HiCrome UTI Agar and MacConkey Agar

Introduction: Urinary Tract Infections (UTIs) are commonly caused by both Gram-negative and Gram-positive bacteria. In clinical microbiology, urine culture plays a crucial role in diagnosis, with traditional media like blood agar and MacConkey agar being widely used. However, Cystine Lactose Electrolyte Deficient (CLED) agar offers a more cost-effective alternative by inhibiting the swarming of Proteus species while supporting a wide range of uropathogens. Chromogenic media, such as HiCrome UTI agar, enable rapid identification but are limited by their high cost. Aim: To compare the diagnostic efficiency of CLED agar, HiCrome UTI agar, and MacConkey agar for the isolation and identification of common urinary tract pathogens. Materials and Methods: This cross-sectional comparative study was conducted in the microbiology department of Shri M.P. Shah Govt. Medical College, Jamnagar, Gujarat, India from October 2019 to December 2020. A total of 400 urine samples from patients with suspected UTIs, collected from both the outpatient and inpatient departments of a tertiary care hospital, were included for bacterial examination. Patients were instructed to collect clean-catch midstream or catheter-catch urine in sterile containers following aseptic protocols. Demographic data such as age, sex, and clinical symptoms were recorded. Statistical analysis was performed using the Chi-square test, with a p-value of <0.05 considered statistically significant. Results: Out of the 400 urine samples processed, 189 (47.3%) showed significant growth, with 158 (83.6%) exhibiting pure bacterial growth and 31 (16.4%) showing mixed bacterial growth. A total of 220 bacterial isolates were identified, predominantly Gram-negative bacilli (85%), with Escherichia coli (44.1%) and Klebsiella spp. (30.5%) being the most common pathogens. Among Gram-positive cocci, Staphylococcus aureus (9.1%) and Enterococcus spp. (5.9%) were prevalent. CLED agar, MacConkey agar, and HiCrome UTI agar all isolated Gramnegative bacteria, but only CLED and HiCrome UTI agar supported the growth of Gram-positive cocci. Mixed bacterial growth was observed in 31 samples, with E. coli and Klebsiella spp. being the most frequent combination. A cost comparison revealed CLED agar as the most economical and effective choice for routine use in resource-limited settings. Conclusion: This study emphasises the need for strategic selection of culture media to enhance the diagnostic efficiency of UTIs, particularly in resource-limited settings. The comparative analysis highlights CLED agar as a cost-effective and reliable option, balancing diagnostic accuracy with affordability. While HiCrome UTI agar offers the advantage of rapid presumptive identification, its higher cost may limit its routine use. The findings provide valuable insights for clinical microbiology laboratories aiming to optimise resource allocation without compromising diagnostic quality