A 34-year-old woman with recurrent urinary tract infections has a plain radiograph showing a large branching calculus filling the left renal pelvis and extending into all the calyces. Urine culture grows Proteus mirabilis. The most appropriate treatment is:

• A Extracorporeal shock wave lithotripsy monotherapy
• B Antibiotic suppression therapy alone with annual radiographs
• C Open nephrolithotomy in all cases
• D Percutaneous nephrolithotomy ✓

Explanation

A staghorn calculus filling the pelvis and calyces is typically composed of struvite, magnesium ammonium phosphate, formed by urease producing organisms such as Proteus. Left untreated it causes progressive renal destruction and sepsis, so active removal is indicated even when asymptomatic. Percutaneous nephrolithotomy is the first line treatment, often combined with adjunctive lithotripsy for residual fragments. Shock wave lithotripsy alone leaves significant fragments, and open surgery is now reserved for selected complex cases.

Reference: Campbell-Walsh Urology, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.