Urologic Evaluation and Diagnostic Imaging
What this domain tests
This domain tests whether you can build a urologic diagnosis from history, examination, urinalysis, laboratory tests, imaging, endoscopy, and urodynamics, and choose the least invasive test that changes management.
Core rules and concepts
- Urinalysis dipstick leukocyte esterase and nitrite are screening tests; microscopy confirms pyuria and hematuria. Sterile pyuria suggests tuberculosis, stones, interstitial cystitis, or recently treated infection.
- Visible hematuria requires cystoscopy and upper-tract imaging. CT urography is preferred in adults at risk for urothelial cancer; ultrasound is an alternative in pregnancy or contrast allergy.
- PSA is organ-specific, not cancer-specific. DRE, prostate volume, age, and risk calculators improve interpretation. PSA can rise with benign prostatic enlargement, prostatitis, catheterization, and ejaculation.
- Urodynamics: filling cystometry assesses compliance, detrusor overactivity, and sensation; pressure-flow study separates detrusor underactivity from outlet obstruction. Order it when the result will change care.
- Endoscopy: flexible cystoscopy suits surveillance and biopsy; rigid instruments allow resection. Record lesion size, location, multiplicity, and completeness.
Worked example
A 64-year-old smoker has painless gross hematuria. Reasoning: smoking and age place him at high risk for urothelial carcinoma. Order CT urography and cystoscopy; urine cytology is adjunctive, not exclusionary. Do not stop at a normal ultrasound or treat as urinary tract infection without follow-up.
Traps
Do not call microscopic hematuria benign without risk assessment. Do not order urodynamics for uncomplicated stress incontinence before conservative therapy. Do not use urine cytology to rule out cancer, because sensitivity is low for low-grade tumors.