An 80-year-old man with benign prostatic hyperplasia passes no urine for 14 hours and has suprapubic discomfort. Creatinine has risen from 1.1 to 3.0 mg/dL over 2 days. Which investigation should be performed first?

• A Contrast-enhanced CT urogram
• B Cystoscopy under anaesthesia
• C Radionuclide renogram with DTPA
• D Bedside ultrasonography of the kidneys and bladder ✓

Explanation

Complete anuria in an older man almost always means obstruction, either at the bladder outlet or bilaterally at the ureters, and postrenal AKI is fully reversible if relieved early. Ultrasonography is the first-line study: it demonstrates a distended bladder, bilateral hydronephrosis, and can be done immediately at the bedside without contrast or radiation. CT urogram adds detail but costs time and iodinated contrast in a patient with rising creatinine. Renography assesses differential function later, and cystoscopy is therapeutic, not diagnostic first step. Bladder catheterisation follows sonography.

Reference: Bailey and Love's Short Practice of Surgery, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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