Results of Non-Surgical Treatment of Uric Acid and Cystine Calculi

Abstract

Of 1,650 patients who underwent extracorporeal shock wave lithotripsy (ESWL) treatment for renal calculi at UCLA between March 1985 and October 1987, 48 patients (2.97%) had symptomatic uric acid stones and ten patients (0.61%) suffered from symptoms of cystine calculi. Treatment consisted of ESWL combined with urinary alkalinization. Prior to ESWL, radiolucent stones were focused as filling defects on retrograde pyelography. In some cases additional renal ultrasound was necessary to identify the stone-bearing calices. At the three-month follow-up, 34 of 48 (70.8%) patients treated for uric acid stones were stone free; at six months, 40 of 48 (83.3%) patients. In the cystine group five of ten (50%) were stone free after six months. Thirty-six of 48 uric acid stone patients and all cystine stone patients required auxiliary procedures such as placement of percutaneous nephrostomy tubes or double-J stents. Two of the cystine stone patients underwent secondary percutaneous stone surgery to remove larger residual stones for a final stone-free rate of 87.5%. The guidelines for treatment of uric acid and cystine lithiasis in the upper urinary tract are described.