A 45-year-old woman with recurrent urinary tract infection is found on plain X-ray to have a large branched calculus occupying the renal pelvis and all the calyces of the right kidney. Urine culture grows a urease-producing organism. What is the preferred treatment?

• A Percutaneous nephrolithotomy ✓
• B Extracorporeal shock wave lithotripsy alone
• C Open pyelolithotomy
• D Medical dissolution therapy with potassium citrate

Explanation

B branched calculus filling the pelvis and calyces is a staghorn calculus, usually composed of struvite (magnesium ammonium phosphate) secondary to urease-producing organisms such as Proteus. Untreated, it leads to chronic infection and progressive renal destruction. Percutaneous nephrolithotomy is the mainstay of treatment, often combined with ESWL as sandwich therapy for residual fragments, and gives the best stone-free rates for complete staghorn stones. ESWL monotherapy leaves significant fragments, and medical dissolution is ineffective for struvite.

Reference: Smith and Tanagho's General Urology, 19th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.