Comparative analysis of different loop types for urine culture collection: Implications for quantitative bacterial growth and culture results

We hypothesized that the loop material and size could affect the results of the culture when compared to the calibrated pipette. A total of 484 urine samples were included in the study, and each sample was plated by using different loop types and the calibrated pipette. The bacterial counts per milliliter were calculated and compared, with a focus on the important cutoff values of 103 and 104 CFU/ml for further identification. When considering the 103 CFU/ml as cutoff value, 1 mu l and 10 mu l plastic loops gave the highest sensitivity (86.8 %), whereas the 10 mu l metal loop had the lowest sensitivity (64.2 %). For the 104 CFU/ml cutoff value, 1 mu l plastic loop inoculation demonstrated the highest sensitivity (75.9 %), while the 10 mu l metal loop provided the lowest sensitivity (26.5 %). These results suggest that the single use plastic loops are functional, sensitive, useful especially for critical sample.