Urologic Procedures and Diagnostic Testing
This domain tests whether you understand what each test measures, its limitations, and the nursing responsibilities before and after urologic procedures.
Urine testing
- Dipstick leukocyte esterase and nitrite is a screen only; microscopy and culture confirm.
- The classic significant colony count is 10^5 CFU/mL, but symptomatic cystitis can be diagnosed at lower counts; mixed flora usually means contamination.
- Cytology is surveillance for high-grade urothelial carcinoma, not a screening test, and a negative result does not exclude low-grade tumors.
- Stone evaluation includes a 24-hour urine panel plus serum calcium, parathyroid hormone, and uric acid.
Serum and tumor markers
PSA is affected by ejaculation, cycling, digital rectal exam, prostatitis, and BPH; a rise is repeated before biopsy. Testicular germ cell markers (AFP, hCG, LDH) are drawn before orchiectomy. Creatinine and eGFR precede contrast and nephrotoxic drugs.
Imaging
CT urography is best for stones and upper tract lesions but carries radiation burden; low-dose CT KUB targets stones; renal ultrasound evaluates hydronephrosis without radiation and is preferred in pregnancy; MAG3 assesses obstruction and function; DMSA assesses scarring; cystography and retrograde urethrography evaluate reflux, leak, and stricture.
Procedures and the nursing role
Cystoscopy (lidocaine jelly; expect dysuria and minor hematuria), TURBT, ureteroscopy, shockwave lithotripsy, and transrectal prostate biopsy (enema, antibiotic prophylaxis, anticoagulation plan). Urodynamics requires holding anticholinergics per order and obtaining uroflow before catheterization.
Worked example
A 65-year-old on warfarin is scheduled for transrectal prostate biopsy. Reasoning: bleeding risk is the dominant issue, so an INR and a cardiology-directed hold or bridge are required, along with antibiotic prophylaxis and the prescribed enema. Afterward, gross hematuria and hematospermia are expected for days to weeks, but fever, inability to void, or worsening pain are not and require urgent contact.
Traps that cost marks
- Calling urine cytology a screening test.
- Repeating a PSA within days of ejaculation or a rectal exam.
- Treating expected post-biopsy hematuria as a complication while ignoring fever.
- Omitting pregnancy screening before abdominal CT.