From the Guidelines
To obtain a urine culture specimen from a Foley catheter, it is recommended to collect the sample after changing the catheter and allowing for urine accumulation while plugging the catheter, using aseptic technique to minimize contamination. This approach is supported by the most recent guideline from 2021, which emphasizes the importance of obtaining the urine culture specimen after changing the catheter and allowing for urine accumulation 1. The steps to collect the specimen include:
- Gathering supplies such as alcohol swabs, a sterile syringe, a sterile specimen container, and clean gloves
- Clamping the catheter tubing below the sampling port for 15-30 minutes to allow fresh urine to accumulate
- Cleaning the sampling port thoroughly with an alcohol swab and allowing it to dry completely
- Inserting the sterile needle or needleless syringe into the sampling port at a 90-degree angle and withdrawing 5-10 mL of urine
- Transferring the urine to the sterile specimen container without contaminating the inside of the container or lid
- Labeling the specimen with patient information, date, time, and noting that it was collected from a Foley catheter
- Transporting the specimen to the laboratory within 30 minutes or refrigerating it if there will be a delay, as recommended by the Infectious Diseases Society of America 1. It is essential to use aseptic technique throughout this process to prevent introducing new bacteria into the catheter system or contaminating the specimen.
From the Research
Obtaining a Urine Culture Specimen from a Foley Catheter
To obtain a urine culture specimen from a Foley catheter, it is essential to follow a standardized technique to minimize contamination and ensure accurate results.
- The study 2 compared the results of urine cultures from male nursing home patients wearing external catheters, collected by a simple standardized technique, with culture results from the same patients obtained by sterile in-and-out catheterization.
- The culture results were the same in 22 (85%) of the matched specimens, and specimens collected by the standardized technique were 100% sensitive and 94% specific in detecting significant growth of pathogenic organisms.
Methods for Obtaining Urine Culture Specimens
There are different methods for obtaining urine culture specimens, including:
- Using a sterile in-and-out catheterization technique 2
- Collecting a midstream urine specimen 3
- Using an antibiotic hydrogel coated Foley catheter to prevent urinary tract infection 4
Importance of Accurate Urine Culture Specimens
Accurate urine culture specimens are crucial for diagnosing and treating urinary tract infections (UTIs) and for preventing catheter-associated UTIs (CAUTIs) 5, 6.
- The study 6 found that positive results of catheter urine cultures frequently lead to unnecessary antimicrobial prescribing, which can contribute to the development of antibiotic-resistant bacteria.
- The study 5 highlighted the importance of considering the polymicrobial nature of CAUTIs when diagnosing and treating these infections.