Urethral stricture following endoscopic prostate surgery: a systematic review and meta-analysis of prospective, randomized trials.

INTRODUCTION AND OBJECTIVES: This systematic review aims to evaluate the incidence and influencing factors of urethral stricture (US) in relation to different BPH endoscopic techniques. MATERIALS AND METHODS: We performed a systematic literature review using MEDLINE, EMBASE, and Cochrane Central Controlled Register of Trials. The incidence of US was estimated through comparative studies between different endoscopic techniques. Patients were assigned into groups according to the type of surgery (enucleation, ablation and resection group). Incidences of US were pooled using the Cochran-Mantel-Haenszel Method with the random effect model and reported as Risk Ratio (RR), 95% Confidence Intervals (CI), and p-values. RESULTS: A total of 80 studies were included for meta-analysis. The pooled incidence of US was 1.7% after enucleation, 2.1% after ablation, 3.8% after monopolar (M)-TURP and 2.1% after bipolar (B)-TURP. The incidence of US was significantly lower after Enucleation than after TURP (RR 0.58 95% CI 0.39-0.84, p = 0.004). US incidence was lower for Ablation procedures than TURP, but the difference did not reach significance (RR 0.79 95% CI 0.61-1.3, p = 0.08). However, this was significant in the subgroup of M-TURP studies (RR 0.67, 95% CI, 0.49-0.91, p = 0.01). Sub-analysis showed that the risk of US was significantly lower after Enucleation than after TURP within 12 months after surgery (RR 0.51 95% CI 0.33-0.81, p = 0.004). CONCLUSION: The study shows an increased incidence of US after TURP compared to enucleation and ablation procedures. The main factors related to increased US incidence are the use of monopolar energy, instrument caliber and duration of postoperative catheterization.

Tea and coffee consumption and the risk of urinary stones-a systematic review of the epidemiological data.

OBJECTIVE: To explore the relationship between the consumption of coffee and tea with urolithiasis. We evaluated large epidemiological and small clinical studies to draw conclusions regarding their lithogenic risk. METHODS: A systematic review was performed using the Medline and Scopus databases, in concordance with the PRISMA statement. English, French, and Spanish language studies regarding the consumption of caffeinated and decaffeinated coffee and tea, and the relationship to urinary stone disease were reviewed. Case reports and letters, unpublished studies, posters, and comments were excluded. RESULTS: As per the inclusion criteria, 13 studies were included in the final review. Most studies, including four large prospective studies and one meta-analysis, reported a reduced risk of stone formation for coffee and tea. Caffeine has a diuretic effect and increases the urinary excretion of calcium, but if these losses are compensated for, moderate caffeine intakes may have little or no deleterious effects. Green and Herbal teas infused for short time had low oxalate content compared to black tea. CONCLUSION: There is no evidence that moderate consumption of coffee raises the risk for stone formation in healthy individuals, provided the recommended daily fluid intake is maintained. The currently available literature supports in general a protective role for tea against the stone formation, mainly for green tea. However, heterogeneity of published data and lack of standardization needs to be addressed before final and clear conclusions can be given to patients and to the public in general.

Tea and coffee consumption and pathophysiology related to kidney stone formation: a systematic review.

OBJECTIVE: To explore the mechanisms behind the potential protective effect of coffee and tea consumption, regarding urinary stone formation, previously demonstrated in large epidemiological studies. METHODS: A systematic review was performed using the Medline, Cochrane library (CENTRAL) and Scopus databases, in concordance with the PRISMA statement. English, French and Spanish language studies, regarding the consumption of caffeinated and decaffeinated coffee and tea, and the relationship to urinary stone formation were reviewed. Meta-analyses, systematic reviews, case reports and letters, unpublished studies, posters and comments abstracts were excluded. RESULTS: As per the inclusion criteria, 13 studies were included in the final review. The major findings show that caffeine increases urinary excretion of calcium, sodium and magnesium, in addition to a diuretic action with consumption > 300-360 mg (approximately four cups of coffee). Together with other components of coffee, this beverage might have potential protective effects against the formation of urinary stones. Tea exerts many protective effects against stone formation, through the accompanying water intake, the action of caffeine and the effects of components with antioxidant properties. CONCLUSION: Caffeine has a hypercalciuric effect, balanced partially by a diuretic effect which appears after consumption of large quantities of caffeine. The current available literature supports in general, a potentially protective role for tea against stone formation, mainly for green tea. Additional standardization in this field of research, through specification of tea and coffee types studied, and their respective compositions, is needed for further clarification of the relation between coffee, tea and urinary stones.