Urological Research最新文献

The incidence of calcium oxalate (CaOx) urolithiasis in dogs has increased steadily over the last two decades. A potential mechanism to minimize CaOx urolithiasis is to reduce enteric absorption of dietary oxalate by oxalate-metabolizing enteric bacteria. Enteric colonization of Oxalobacter formigenes, an anaerobe which exclusively relies on oxalate metabolism for energy, is correlated with absence of hyperoxaluria or CaOx urolithiasis or both in humans and laboratory animals. We thus hypothesized that decreased enteric colonization of O. formigenes is a risk factor for CaOx urolithiasis in dogs. Fecal samples from dogs with CaOx uroliths, clinically healthy, age-, breed- and gender-matched dogs, and healthy non-stone forming breed dogs were screened for the presence of O. formigenes by quantitative PCR to detect the oxalyl CoA decarboxylase (oxc) gene, and by oxalate degrading biochemical activity in fecal cultures. Prevalence of O. formigenes in dogs with CaOx uroliths was 25%, compared to 50% in clinically healthy, age-, breed- and gender-matched dogs, and 75% in healthy non-stone forming breeds. The presence of oxc genes of O. formigenes was significantly higher in healthy non-stone forming breed dogs than in the dogs with CaOx stones. Further, dogs with calcium oxalate stones and the stone-forming breed-matched controls showed comparable levels of biochemical oxalate degrading activity. We conclude that the absence of enteric colonization of O. formigenes is a risk factor for CaOx urolithiasis.

Kidney stones represent a common condition characterized by significant morbidity and economic costs. The epidemiology of kidney stones is not completely understood and may vary substantially based on geographic, socioeconomic and clinical factors; the present study aims at defining the prevalence and diagnostic patterns of kidney stones in a cohort representative of the general population in Florence, Italy. A sample of 1,543 adult subjects, all Caucasians, was randomly selected from a population of over 25,000 subjects followed by 22 general practitioners (GPs). Subjects were administered a questionnaire requesting the patient's age and sex, any history of kidney stones and/or colics and the prescription of kidney ultrasound (US) examination. GPs data-bases were also interrogated. Crude and adjusted prevalence proportions and ratios (PRs) with corresponding 95% confidence intervals (CIs) were computed. Furthermore, the association between the practice pattern of each physician with respect to US prescription and the prevalence of kidney stones was investigated. The overall prevalence of kidney stones was 7.5% (95% confidence interval 6.2, 8.9%), increasing with age until 55-60 years and then decreasing. About 50% reported recurrent disease. There were no significant differences in prevalence among males and females. GPs who tended to prescribe more US examinations were more likely to have more patients with kidney stones (adjusted PR 1.80, 95% CI 1.11, 2.94; p = 0.020). The present study confirms both the high prevalence and the regional variability of kidney stones. Practice patterns may be involved in such variability.

The present review summarizes the most important considerations and steps for an optimal result of extracorporeal shockwave lithotripsy. The relationship between shockwave path, geometry and anatomical conditions is of utmost importance. Selection of appropriate treatment variables in terms of shockwave number, power and frequency, is an important prerequisite for proper disintegration and prevention of complications. Several supportive measures such as inversion therapy, citrate therapy, high diuresis, α-receptor antagonists, chemolysis and recurrence preventive measures are important parts of the management of this group of patients in order to avoid problems with residual fragments and new stone formation. Proper understanding of these factors as well as of the physics of shockwaves is necessary for a successful application of this non-invasive technology treatment concept.

The aim of this study is to evaluate the efficacy of alfuzosin with methylprednisolone on expulsion and pain control of lower ureteral stones <10 mm in size. Between June 2005 and June 2007, 113 patients with lower ureteral stones <10 mm in size were enrolled in the study. The patients were divided into a control group (group I) and medical expulsive therapy group (group II). Group I (n = 66) received oral analgesics daily and group II (n = 47) received the same analgesics along with 10 mg alfuzosin and 8 mg methylprednisolone for 4 weeks orally once a day. The treatment was continued until stone expulsion or to a maximum of 4 weeks. All patients were allowed 25 mg pethidine hydrochloride intramuscular injections if needed for suboptimal pain control. The average stone size was 6.15 mm in group I and 5.42 mm in group II. Of the 113 patients, 80 became stone free (70.7%). Group II had significantly higher stone free rates (82.9 vs. 62.1%, p = 0.014), fewer expulsion times (mean 4.4 vs. 7.3 days, p = 0.001), and mean number of intramuscular analgesic injections (0.8 vs. 2.1) compared to group I. Alfuzosin with methylprednisolone treatment seems safe and effective for lower ureteral stones <10 mm in size as demonstrated by the increased stone free rate, earlier expulsion, and reduced additional analgesic therapy.

Patient collaboration in external shock wave lithotripsy (ESWL) is critical for its correct application, making proper analgesic selection indispensable. The aim of this study was to evaluate the efficacy of combined application of EMLA and intravenous (i.v.) pethidine compared with pethidine plus placebo cream in patients undergoing ESWL for ureteral and/or renal lithiasis. Prospective, controlled, randomized, double-blind study was conducted in patients receiving ESWL for renal and/or ureterolithiasis. The patients were randomly assigned to receive i.v. pethidine plus either EMLA cream (group A) or placebo hydrating cream (group B). Evaluated were type, location, and size of lithiasis, patient's sex, age, body mass index, comorbidity, Visual Analogue Scale (VAS) score of pain, and degree of lithiasis fragmentation. EMLA cream provided significantly better pain relief and lithiasis fragmentation and more completed ESWL treatment. Topical application of EMLA cream combined with i.v. pethidine improved VAS scores and lithiasis fragmentation and decreased the rate of withdrawal from ESWL procedure versus i.v. pethidine plus placebo therapy.

The aim of the study was to evaluate the impact of age on the efficacy of extracorporeal shock wave lithotripsy (SWL), in a comparative study based on the principles of matched-pair analysis. Over a period of 4 years, 2,311 patients were treated with SWL in a tertiary referral center. Patient and stone data were recorded in a prospective electronic database. Among these patients, 115 (4.97%) were older than 70 years of age and fulfilled the criteria for inclusion in the study (Group A). For the purposes of the comparative analysis, Group A patients were matched for gender and stone parameters (side, location of stone, and diameter ±2 mm) with a control group of patients under the age of 70 (Group B). Following matching, the patients' electronic medical records were reviewed, to identify SWL success rates at 3 months and McNemar's test was used to compare the efficacy of SWL between the two groups. Matching was possible in all cases. The results indicate that there were no statistically significant differences in the mean number of SWL sessions or in the mean number of impulses per session between the two groups. The overall stone clearance rate achieved by SWL alone was 71.3% for Group A and 73.9% for group B. Discordant pairs were found in 37 cases (in 17 pairs only patients in Group A became stone-free, while in 20 pairs only patients in Group B became stone-free). By using McNemar's test, the difference in stone clearance rates between the two groups was not found to be statistically significant (p = 0.742). A total of 22 patients (19.1%) in Group A and 17 patients (14.7%) in Group B underwent an adjuvant procedure to achieve stone clearance. McNemar's test also revealed the absence of any statistically significant difference in SWL success rates between older and younger patients in the subgroups of patients presenting with either ureteric or renal stones (p = 0.727 and p = 0.571, respectively). In conclusion, SWL is still considered one of the first-line tools for geriatric patients suffering from urolithiasis, as increased age alone does not seem to adversely affect the efficacy of SWL.

Almost all kidney stones are CT positive. Before a CT scan can be done a CT planning image (CTI) is generated in order to select the exact scanning area. The CTI looks approximately like a normal kidney-ureter-bladder abdominal radiography (KUB) but with reduced quality. It has been used as a guide, assuming that if the kidney stone could be seen on the CTI the kidney stone also would be visible on a conventional plain KUB (radiopaque). From the perspective of diagnosis and treatment as well as follow-up it is of importance to know whether a kidney stone is radiopaque or not. The aim of this study was to evaluate whether the CTI actually can predict radiopacity. CT scans and corresponding KUB's were analysed in 76 consecutive kidney stone patients. The CT scan and the KUB were performed on the same day. All patients were examined with the same CT scanner (64 slice GE light speed VCT). Three radiologists evaluated the images in plenum. The following was recorded regarding the kidney stones: X-ray positive (radiopaque on KUB), CTI positive (radiopaque on CTI), location (a kidney, b upper two-thirds of ureter and c lower one-thirds of ureter including the bladder), size and Hounsfield units (HU). We also measured the patient's 'anterior-posterior depth' (APD) at the kidney stone level in axial plane, and whether the stone was homogeneous/inhomogeneous. 54 of the 76 patients (71%) had radiopaque stones on KUB. 43 (57%) of these also could be seen on the CTI, resulting in a positive predicting value (PPV) of 100% and a negative predictive value (NPV) of 67%. In the 54 KUB positive kidney stones the mean kidney stone diameter was 7 mm (2-30 mm), mean HU's 1,007 (294-1,782 HU), location: a:32, b:9 and c:13 patients. APD was mean 23.6 cm (13-39 cm). In the KUB positive and CTI negative kidney stones (11 patients) mean kidney stone diameter was 4 mm (2-9 mm), mean HU's 742 (294-1,253 HU), location: a:32, b:9 and c:13 patients. APD in this group was mean 26.1 cm (13-37 cm). If the kidney stone can be seen on the CTI it is also visible on a plain KUB (PPV 100%). The CTI do, however, underestimate the radiopacity of a stone on a plain KUB (NPV 67%). Kidney stone HU > 742, stone location in the kidney and proximal ureter and APD < 26 cm independently predict agreement between CTI and KUB with regard to radiopacity.