What are the two preferred methods of collecting a urine sample for culture?

What are the two preferred methods of collecting a urine sample for culture?

• A. Catheterization and voiding
• B. Expressing the bladder and cystocentesis
• C. Cystocentesis and catheterization
• D. Cystocentesis and voiding

Answer: (C)

When collecting urine for culture, you want a sample that truly represents the bladder contents with minimal contamination from skin, genitalia, or the environment. The two best methods for achieving this are cystocentesis and catheterization. Cystocentesis involves inserting a needle into the bladder under aseptic conditions to withdraw urine directly from the bladder, which makes the sample Very unlikely to be contaminated by urethral or external flora, giving a nearly ideal specimen for culture. Catheterization uses a sterile urinary catheter passed through the urethra into the bladder to collect urine; this method reduces contamination compared with a free catch because the sample is obtained after the urethra has been traversed, though it carries some risk of urethral trauma or introducing infection. In contrast, collecting by voiding or attempting to express the bladder tends to mix urine with periurethral or environmental contaminants, which can compromise culture accuracy.

When collecting urine for culture, you want a sample that truly represents the bladder contents with minimal contamination from skin, genitalia, or the environment. The two best methods for achieving this are cystocentesis and catheterization. Cystocentesis involves inserting a needle into the bladder under aseptic conditions to withdraw urine directly from the bladder, which makes the sample Very unlikely to be contaminated by urethral or external flora, giving a nearly ideal specimen for culture. Catheterization uses a sterile urinary catheter passed through the urethra into the bladder to collect urine; this method reduces contamination compared with a free catch because the sample is obtained after the urethra has been traversed, though it carries some risk of urethral trauma or introducing infection. In contrast, collecting by voiding or attempting to express the bladder tends to mix urine with periurethral or environmental contaminants, which can compromise culture accuracy.