The effect of citrate replacement in hypocitraturic cases on the results of SWL: a preliminary prospective randomized study

To evaluate the possible effects of citrate replacement on the efficacy of shockwave lithotripsy (SWL) in the management of kidney stones in cases with hypocitraturia.

Forty hypocitraturic cases with renal pelvic stones were randomized into two groups; while citrate replacement has been done before and at the time of SWL in Study Group I (n: 20), SWL was performed without any additional specific management for hypocitraturia in Study Group II (n: 20). Twenty normocitraturic cases were also chosen as the control group (Group III). Data of the patients were evaluated comparatively.

Patient, stone, and urinary pH characteristics of the groups were similar. Pre-SWL urinary citrate levels were 0.71 (0.1–1.3), 0.86 (0.1–1.4), and 3.12 (1.8–4.4) mmol/24 h in Group I, II, and III, respectively. Urinary citrate value increased from 0.71 (0.1–1.3) to 1.96 (1.6–4.1) mmol/24 h following replacement therapy (before and at the time of SWL) in Group I. Mean number of SW (p = 0.461), rate of stone-street formation (p = 0.146), and Double-J placement (p = 0.291) were similar in Group I and Group II. While the mean number of SWL sessions (2.27 ± 0.71 in Group I vs. 2.94 ± 0.59 in Group II; p = 0.027), and time to stone-free status [29.1 (16–47) days in Group I vs. 38.4(21–63) days in Group II; p = 0.043], was significantly different between study groups, these parameters were found similar between Group I and Group III.

In our study, the patients with hypocitraturia, who did receive replacement therapy, tended to require lower number of SWL sessions and became stone free in a shorter period than the others who underwent SWL without any specific management of hypocitraturia.