Dissolution of Residual Microfragments with Citrate Therapy after Extracorporeal Shock Wave Lithotripsy

Abstract

Kesidtial microiragmcnfs after ESWL were studied for their presence and for possibility of dissolution with citrate therapy. Among 123 patients with renal stones who became stone-free following ESWL, a computed toiiiogr.ini (CT) itientifiecl remaining microfragments within the treated kidney in 31.7% of the patients, even though stone fragments were not detectable on ordinary x-ray (KUU). The experiments, in which calcium oxalate stone fragments c-ollected <liter ESWL were incubated in buiter solutions with titrate 0 to 4 nmol/L, showed that citrate dissolved the stone fragments. Using human urine as a solution, the dissolving effect was greater in spot urines after aIk'>li citrate administration than in control urines. Eighteen patients with microfragments underwent a follow-up CT I months later, The rcsults showed that thc microfragments had disappeared in 6 of 11 (53.5%) p-'.itients who had beer1 t,iking .11kaIi citrate, whereas microfragments remained unchariged in all 3 patients wlthout niedication. Our results suggest that citratr therapy would be advisable as d prophylaxis tor stone recurrence especially after ESWL treatniriit. Int J Urol 1996;3(suppl 1 ):S85-S87