NEW YORK (Reuters Health) – If asymptomatic lower pole renal calculi require intervention, percutaneous nephrolithotomy will provide a higher stone-free rate than shock wave lithotripsy, and with less scarring, Turkish researchers report.
According to their article in the April Journal of Urology, more than half of patients with asymptomatic caliceal stones will require intervention within five years. To compare treatments and expectant management, Dr. Ahmet Tefekli from Haseki Teaching and Research Hospital in Istanbul and colleagues randomized 94 patients to nephrolithotomy, lithotripsy, or observation groups.
They evaluated patients’ stone status with non-contrast abdominal computed tomography, and they monitored for renal scarring with dimercapto-succinic acid scintigraphy.
All 31 subjects in the nephrolithotomy group were stone free at 12 months. One patient (3.2%) had scarring at 3 months.
With lithotripsy, however, only 19 of 31 patients (61.3%) were stone free at 12 months, and five patients (16.1%) had renal scarring.
Over an average of 20 months, 7 (18.7%) of 32 patients in the observation group required intervention, and one (3.1%) spontaneously passed the stone. No patient in the observation group had renal scarring.
“Patients with asymptomatic lower caliceal stones must be informed in detail about all management options, especially focusing on percutaneous nephrolithotomy with its outstanding outcome,” the authors conclude.
They add that these results “must be further evaluated by comparison with new digital flexible ureterorenoscopy devices.”
J Urol 2010;183:1424-1428.