Majzoub A et al, 2016: Effect of urine pH on the effectiveness of shock wave lithotripsy: A pilot study.
Majzoub A, Al-Ani A, Gul T, Kamkoum H, Al-Jalham K.
Department of Urology, Hamad Medical Corporation, Doha, Qatar.
AIM: Shock wave lithotripsy (SWL) is a well-established modality in the treatment of urolithiasis. Studying the effect of urine pH on SWL success is appealing as pH can be manipulated before SWL to insure a better outcome.
MATERIALS AND METHODS: This is a prospective study performed at a tertiary medical center. Patients presenting to the SWL unit with a single renal stone <2 cm in size were included in this study. In addition to standard laboratory and radiologic investigations, urine pH measurement was performed on all patients before their procedure. The number of sessions performed, and the stone-free rate (SFR) were assessed. Patients were divided into two groups according to stone clearance. Group 1 was stone-free, whereas Group 2 had residual stones after three sessions of SWL. Data was also classified according to different pH ranges. Influential factors were compared among the study groups and pH ranges.
RESULTS: A total of 175 patients were included in this study. The SFR was 54.3%. The mean number of sessions performed was 2.2 ± 0.8. Group 1 included 95 patients, whereas Group 2 had eighty patients. Among all studied factors, stone size (P = 0.03) and skin to stone distance (P = 0.04) significantly affected SFR with SWL. Urine pH was not found to have a statistically significant influence on SWL outcome (P = 0.51).
CONCLUSION: Urine pH was not found in this study population to influence the effectiveness of SWL. Further experimental studies are required to help investigate this notion.
Urol Ann. 2016 Jul-Sep;8(3):286-90. doi: 10.4103/0974-7796.184899. FREE ARTICLE
It is well known that the urinary pH varies during 24 hrs from around 5-6,5 in night-time and morning to 7-8 during the day-time. The mean pH values of 5,6 or 5,8 in the two groups probably only reflect the fact that the treatments were done in the morning hours. I would not spend more time on in vivo studies and I do not think that the pH within the physiological range will have an influence on stone disintegration.