Urinary volume, water and recurrences in idiopathic calcium nephrolithiasis: a 5-year randomized prospective study. Unprocessed bran and intermittent thiazide therapy in prevention of recurrent urinary calcium stones. Randomized prospective study of a nonthiazide diuretic, indapamide, in preventing calcium stone recurrences. Randomised trial of cranberry-lingonberry juice and Lactobacillus GG drink for the prevention of urinary tract infections in women. Treatment for extended-mid and distal ureteral stones: SWL or ureteroscopy? Results of a multicenter study. A prospective randomized study comparing shock wave lithotripsy and semirigid ureteroscopy for the management of proximal ureteral calculi. Functional bladder capacity as predictor of response to desmopressin and retention control training in monosymptomatic nocturnal enuresis. Clinical significance of primary vesicoureteral reflux and urinary antibiotic prophylaxis after acute pyelonephritis: a multicenter, randomized, controlled study. Maternal hydration increases amniotic fluid index in women with normal amniotic fluid.
We define the role of urine volume as a stone risk factor in idiopathic calcium stone disease and test the actual preventive effectiveness of a high water intake.
                We studied 101 controls and 199 patients from the first idiopathic calcium stone episode. After a baseline study period the stone formers were divided by randomization into 2 groups (1 and 2) and they were followed prospectively for 5 years. Followup in group 1 only involved a high intake of water without any dietetic change, while followup in group 2 did not involve any treatment. Each year clinical, laboratory and radiological evaluation was obtained to determine urinary stone risk profile (including relative supersaturations of calcium oxalate, brushite and uric acid by Equil 2), recurrence rate and mean time to relapse.
                The original urine volume was lower in male and female stone formers compared to controls (men with calcium oxalate stones 1,057 +/- 238 ml./24 hours versus normal men 1,401 +/- 562 ml./24 hours, p < 0.0001 and women calcium oxalate stones 990 +/- 230 ml./24 hours versus normal women 1,239 +/- 440 ml./24 hours, p < 0.001). During followup recurrences were noted within 5 years in 12 of 99 group 1 patients and in 27 of 100 group 2 patients (p = 0.008). The average interval for recurrences was 38.7 +/- 13.2 months in group 1 and 25.1 +/- 16.4 months in group 2 (p = 0.016). The relative supersaturations for calcium oxalate, brushite and uric acid were much greater in baseline urine of the stone patients in both groups compared to controls. During followup, baseline values decreased sharply only in group 1. Finally the baseline urine in patients with recurrences was characterized by a higher calcium excretion compared to urine of the patients without recurrences in both groups.
                We conclude that urine volume is a real stone risk factor in nephrolithiasis and that a large intake of water is the initial therapy for prevention of stone recurrences. In cases of hypercalciuria it is suitable to prescribe adjuvant specific diets or drug therapy. Both urinary calcium excretion and renal stone episodes are increased during the summer in Finland. Since thiazide and unprocessed bran are known to decrease urinary calcium excretion, we treated 73 patients with recurrent urinary stone formation by giving them unprocessed bran and intermittent thiazide. Of the patients, 32 had absorptive hypercalciuria and 41 had normal urinary calcium values. All patients were on a low-calcium and low-oxalate diet and took 40 g bran daily. Fourteen of the hypercalciuric and 14 of the normocalciuric patients were randomly allocated to use hydrochlorothiazide 50 mg b.i.d. from May to September. Reduction of stone formation was seen in all groups. The combination of thiazide + bran was superior to the bran on its own in inhibition of stone formation. Only 3/11 (27%) stones passed through during the summer in the thiazide + bran group as compared with the 11/17 (65%) in the bran group. We examined the biochemical changes and the efficacy of indapamide in the prevention of calcium stone recurrences. Seventy-five patients with calcium nephrolithiasis and hypercalciuria were randomly assigned to three different therapies: diet and fluid (group A), diet and fluid plus indapamide 2.5 mg/day (group B), and diet and fluid plus indapamide 2.5 mg/day plus allopurinol 300 mg/day (group C). Before treatment and after 6, 12, 24, and 36 months of therapy, we evaluated blood pressure, serum and urine risk parameters (including relative supersaturations of calcium oxalate, calcium phosphate and uric acid), stone rate, and the proportion of calculi-free patients. During the 3 years of treatment, urinary calcium greatly decreased in groups B and C, dropping to 50% of the pretreatment values; urinary oxalate also significantly declined in group B (-24%) and group C (-27%). Relative supersaturations of calcium oxalate and calcium phosphate decreased to the same extent in groups B and C (about one-half of the pretreatment value), and relative supersaturation of uric acid was particularly reduced in group C (-65% of the pretreatment value). The stone rate improved in all three groups (p < 0.005), but using actuarial analysis in the evaluation of calculi-free patients, indapamide, and indapamide plus allopurinol groups were found to have a significantly more favorable effect than diet and fluid treatment (p < 0.02), without any difference between the two drug groups. Because indapamide has fewer side effects than thiazide diuretics, we conclude that indapamide could be an interesting alternative to thiazides in the prevention of calcium stones in hypercalciuric patients. To determine whether recurrences of urinary tract infection can be prevented with cranberry-lingonberry juice or with Lactobacillus GG drink. Design: Open, randomised controlled 12 month follow up trial.
                Health centres for university students and staff of university hospital.
                150 women with urinary tract infection caused by Escherichia coli randomly allocated into three groups. Interventions: 50 ml of cranberry-lingonberry juice concentrate daily for six months or 100 ml of lactobacillus drink five days a week for one year, or no intervention. Main outcome measure: First recurrence of symptomatic urinary tract infection, defined as bacterial growth >/=10(5 )colony forming units/ml in a clean voided midstream urine specimen.
                The cumulative rate of first recurrence of urinary tract infection during the 12 month follow up differed significantly between the groups (P=0.048). At six months, eight (16%) women in the cranberry group, 19 (39%) in the lactobacillus group, and 18 (36%) in the control group had had at least one recurrence. This is a 20% reduction in absolute risk in the cranberry group compared with the control group (95% confidence interval 3% to 36%, P=0.023, number needed to treat=5, 95% confidence interval 3 to 34).
                Regular drinking of cranberry juice but not lactobacillus seems to reduce the recurrence of urinary tract infection. In a randomized study, we analyzed the treatment results of ureterorenoscopy (URS) and shockwave lithotripsy (SWL) for extended-mid and distal ureteral stones. We investigated also, for reasons of cost effectiveness, the factors influencing the outcome, the complications, and the need for auxiliary procedures.
                In three regional hospitals, we selected 156 patients with extended-mid and distal ureteral stones. After randomization, 87 were treated with URS, and 69 with SWL. The treatment results were studied in relation to complications, the need for auxiliary procedures and stone factors, urinary tract infection (UTI), dilatation, and kidney function.
                After retreatment of 45% of the patients, the stone-free rate after 12 weeks in the SWL group was 51%. After a retreatment rate of 9% of the patients in the URS group, the stone-free rate was 91%. Including the number of auxiliary procedures, we calculated the Efficiency Quotient (EQ) as 0.50 for SWL and 0.38 for URS. After correction and redefinition of auxiliary procedures, the EQ was 0.66. The mean treatment time for SWL was 52 minutes and for URS 39 minutes. General anesthesia was more frequently needed in URS patients. Complications occurred more often in the URS group (22 v 3 and 24 v 13, respectively). These were mostly mild, and all could be treated with a double-J stent, antibiotics, or analgetics. A lower stone-free rate was achieved in patients with larger (> or =11 mm) stones (75% v 85% for smaller stones in the URS group and 17% v 73% in the SWL group. In the URS group, the stone-free rate of patients with extended-mid ureteral stones was lower than that of patients with distal ureteral stones. Calculating the costs for URS and SWL appeared impossible because of the differences in available equipment.
                The stone-free rate after URS is much higher than after SWL, and the EQ in our series was strongly dependent on definitions. The decision about how to treat a patient with an extended-mid or distal ureteral stone therefore should not be made primarily on the basis of cost effectiveness but rather on the basis of the availability of proper equipment, the experience of the urologist, and the preference of the patient. To conduct a prospective randomized study comparing both techniques for the management of solitary radio-opaque upper ureteral stones < 2 cm in diameter. The ideal treatment for upper ureteral stones > 1 cm size remains to be determined with shock wave lithotripsy (SWL) and ureteroscopy (URS) being acceptable options.
                A total of 200 patients were included in the study. They were randomized into 2 equal groups. Group A underwent in situ SWL as a primary therapy. Group B underwent URS, using semirigid URS with intracorporeal lithotripsy. Efficiency quotient (EQ), cost analysis, and predictors of failure were estimated for both techniques.
                For stones of size > or = 1 cm, the initial stone-free rate for URS and SWL was 88% and 60%, respectively. The estimated EQ was 0.79 and 0.43 for both techniques respectively. For stones < 1 cm, the initial stone-free rate for URS and SWL was 100% and 80%, respectively. The estimated EQ was 0.88 and 0.70 for both techniques, respectively. The mean cumulative costs were significantly more in SWL group (P <.05). Predictors of URS failure included; male gender, failure to pass guidewire beyond the stone, and extravasation. Predictors of SWL failure included large stone size > 1 cm, calcium oxalate monohydrate stone, and higher degrees of hydronephrosis.
                URS with intracorporeal lithotripsy is an acceptable treatment modality for all proximal ureteral calculi, particularly stones > 1 cm. SWL should remain the first-line therapy for proximal ureteral calculi < or = 1 cm because of the less invasive nature and lower anesthesia (i.v. sedation). To evaluate the efficacy of intranasal desmopressin (DDAVP) and retention control training (RCT) for monosymptomatic nocturnal enuresis in childhood and to assess the predictive value of daytime functional bladder capacity for both methods.
                A total of 114 children with monosymptomatic nocturnal enuresis, of whom 99 (86.8%) wetted the bed every night, were treated with 1 of the 2 methods: intranasal DDAVP in 54 and RCT in 60 subjects.
                Twenty-one of 54 patients (38.9%) and 14 of 60 patients (23.3%) in the DDAVP group and the RCT group, respectively, achieved strong improvement (p = 0.061). Forty-five of 54 (90.0%) in the DDAVP and 35 of 60 (58.3%) in the RCT group had a more than 50% decrease in wet nights (p = 0.004). In the DDAVP group, the functional bladder capacities at baseline in responders and nonresponders were 82+/-22% and 56+/-20% of the predicted bladder capacity for their age (p<0.001). In the RCT group, responders and nonresponders did not differ in functional bladder capacity at baseline.
                DDAVP treatment is more effective than RCT in decreasing the number of wet nights in childhood nocturnal enuresis, but not so effective in children with a low functional bladder capacity. Daytime functional bladder capacity is a valuable predictor of response to DDAVP, but not so to RCT. To evaluate the role of primary vesicoureteral reflux (VUR) in increasing the frequency and severity of urinary tract infections (UTIs) and renal parenchymal damage among patients with acute pyelonephritis and to determine whether urinary antibiotic prophylaxis reduces the frequency and/or severity of UTIs and/or prevents renal parenchymal damage among patients with mild/moderate VUR.
                Patients 3 months to 18 years of age with acute pyelonephritis, with or without VUR, were assigned randomly to receive urinary antibiotic prophylaxis or not. Patients were monitored every 3 months for 1 year. Dimercaptosuccinic acid renal scans were repeated at 6 months or if there was a recurrence of febrile UTI. Urinalysis and urine culture were performed at each clinic visit. Renal ultrasound scans and voiding cystourethrograms were repeated at the end of 1 year of follow-up monitoring.
                Of the 236 patients enrolled in the study, 218 completed the 1-year follow-up monitoring. Groups were similar with respect to age, gender, and reflux grade distribution for those with VUR. No statistically significant differences were found among the groups with respect to rate of recurrent UTI, type of recurrence, rate of subsequent pyelonephritis, and development of renal parenchymal scars.
                After 1 year of follow-up monitoring, mild/moderate VUR does not increase the incidence of UTI, pyelonephritis, or renal scarring after acute pyelonephritis. Moreover, a role for urinary antibiotic prophylaxis in preventing the recurrence of infection and the development of renal scars is not supported by this study. To test the hypothesis that maternal oral hydration would increase the amniotic fluid (AF) index in pregnancies with normal AF.
                Forty women with a normal AF index (7.0-24.0 cm) were randomized to either the control or hydration group. Women in the hydration group drank 2 L of water and returned for the post-treatment AF index in 4-6 hours, whereas women in the control group drank only 100 mL of water during the same time period. The investigator performing the AF index was blinded to the subject's group. The pre- and post-treatment AF indexes and maternal urine specific gravities were compared between the groups.
                The mean AF index in the hydration group increased significantly by 3.0 +/- 2.4 cm (P < or = .0001) whereas it declined significantly by 1.5 +/- 2.7 cm in the control group (P < or = .02). The maternal urine specific gravities also changed significantly in the expected direction, with those in the hydration group decreasing and those in the control group increasing (P < or = .0001). There was a regression coefficient of -0.6 (P < or = .0001) between the change in urine specific gravity and the change in AF index. The mean time between the pre- and post-treatment AF indexes was not different between the groups.
                Maternal oral hydration increased the AF index by approximately 16%, whereas fluid restriction decreased the AF index by 8% in women with normal AF. These findings support previous data that maternal hydration increased the AF index by 31% in women with decreased AF and suggest that maternal fluid volume or osmolality may have a role in maintaining the AF volume.
The evidence from only one study indicates that increased water intake reduces the risk of recurrence of urinary stones and prolongs the average interval for recurrences. However further research is required. Due to the lack of appropriate RCTs, no conclusions can be drawn on increased water intake for the primary and secondary prevention of urinary stones.