Catheter Tip or Direct Urine Culture – Choosing the Better Specimen for Biofilm Detection.

Abstract

Objectives: To assess the better specimen for biofilm detection among catheter tip and direct urine culture and to evaluate the effect of age on biofilm forming capacity of organisms isolated. Study Design: Cross Sectional Descriptive study. Setting: Lahore General Hospital and Department of Microbiology, Post Graduate Medical Institute. Period: August 2018 to February 2019. Material & Methods: Convenient sampling technique was used to collect 75 Catheter tips and corresponding Urine samples from catheterized patients. Catheter tips were cultured by Brun-Buisson technique and Quantitative method was used for culture. The isolates were identified using standard operating procedures and the MDR isolates recovered were subjected to Microtiter plate assay to determine their biofilm forming capacity. Results: The mean age of catheterization was calculated to be 55.8 years. Statistically, similar number of isolates were recovered from catheter tip and urine sample. However, significantly lesser number of urine samples were found positive for growth (p<0.05). MTP assay of catheter tip and urine sample revealed maximum isolates exhibit strong biofilm forming capacity (56.1% vs 47.6%) while minimum number of organisms display no biofilm formation (1.8% vs 2.4%). Catheter tips and urine culture both detect biofilm forming capacity of isolates similarly (p> 0.05). Maximum biofilm formation (100%) is seen in extremes of age. Conclusion: Less number of urine samples were found positive for growth compared to catheter tips but there is no significant difference in detecting biofilm by catheter tip and urine sample.