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PubMed1997

Vesicoureteral reflux diagnosed in adulthood. Incidence of urinary tract infections, hypertension, proteinuria, back pain and renal calculi.

STUDY PURPOSE: To determine the incidence of urinary tract infections, hypertension, back pain, and renal calculi in adult patients with vesicoureteral reflux and reflux nephropathy. METHODS: A group of 115 patients (16-60 years of age, median 28 years) with vesicoureteral reflux, combined with reflux nephropathy in 101 patients, first detected between 1967 and 1984, was studied retrospectively. The group comprised 99 women and 16 men. RESULTS: Symptoms and findings associated with the urinary tract preceded the diagnosis of vesicoureteral reflux by median 14 years (1-60 years). Intravenous pyelography preceded investigation with micturating cystography in 99 patients. Fifteen patients had no urinary tract infections, 17 patients had only lower urinary tract infections, and 83 patients had upper with or without lower urinary tract infections. Females had 12 times more lower and seven times more upper urinary tract infections than males, whereas males had impairment of renal function and proteinuria more often than females. Hypertension was present in 39 patients (34%) and five times more frequent in patients with bilateral than in those with unilateral reflux nephropathy. The median age at the first recording of hypertension was 33 years (16-60 years). Malignant hypertension was uncommon and occurred in two patients. An older group (> 45 years of age at presentation) of 19 patients showed a 90% incidence of hypertension compared with 23% in 96 patients in the younger group (< or = 45 years of age at presentation). Back pain of varying type and severity was present in 48 patients (42%). A total of 38 renal calculi was found in 21 (18%) patients, of whom 14 were completely asymptomatic. CONCLUSIONS: The natural history of vesicoureteral reflux first detected in adulthood has shown a strikingly high incidence of urinary tract infections, arterial hypertension, back pain, and renal calculi.

Adolescent↗
PubMed1995

Indwelling ureteral stents as definitive therapy for distal ureteral calculi.

Distal ureteral calculi are a common urological problem often requiring surgical and anesthetic intervention. In a health care system with limited resources this intervention can lead to the expenditure of significant monies. Ureteral stents are often used to stabilize symptomatic patients preoperatively. Since stent placement causes passive ureteral dilation, we hypothesized that temporary placement of a ureteral catheter would facilitate spontaneous calculus passage. We prospectively studied 27 patients who presented with distal ureteral calculi less than 10 mm. large and met criteria established for surgical intervention. Self-retaining Double-J stents were placed in 10 male and 7 female patients, and left for 2 weeks using only topical anesthesia during the procedures. In the majority of the patients (83%) the calculi passed spontaneously after stent removal, obviating surgical or anesthetic intervention.

Female↗
PubMed1997

The role of percutaneous nephrolithotomy in the management of pediatric renal calculi.

PURPOSE: Minimally invasive techniques for the treatment of urinary calculi in children are recommended due to an increased probability of recurrence. Percutaneous nephrolithotomy is well established in adults but to our knowledge this procedure has not been reported previously in a large series of children. We review our experience with percutaneous nephrolithotomy in children. MATERIALS AND METHODS: From 1987 to 1995 percutaneous nephrolithotomy was performed in 25 children 3 to 16 years old (median age 8). Indications for percutaneous nephrolithotomy were an obstructed kidney in 10 cases, large stone size or staghorn calculus in 8, failed extracorporeal shock wave lithotripsy in 4 and residual stones after open surgery in 3. There were 15 solitary renal, 4 staghorn and 2 upper ureteral stones, and 5 children had multiple renal calculi. RESULTS: Percutaneous nephrolithotomy was performed once in 22 patients, and 2, 3 or 5 times in the remainder. Of the 25 patients 17 (68%) were stone-free at hospital discharge or shortly thereafter following a single session of percutaneous nephrolithotomy. Retained calculi after a single percutaneous nephrolithotomy treatment were much more common with staghorn stones (2 of 4 cases or 50%) and multiple stones (3 of 5 or 60%) compared to solitary renal stones (2 of 15 or 13.3%). With subsequent extracorporeal shock wave lithotripsy or repeat percutaneous nephrolithotomy the stone clearance rate was as high as 92%. At a 2 to 66-month followup (average 23) no late complications were noted. Radioisotope scans available in 10 cases before and after percutaneous nephrolithotomy revealed unchanged differential function and evidence of significant renal scars in only 1. CONCLUSIONS: Percutaneous nephrolithotomy is a suitable and safe procedure for treating renal stones in children.

Adolescent↗
PubMed2004

Extracorporeal lithotripsy for salivary calculi: a long-term clinical experience.

OBJECTIVES/HYPOTHESIS: The objective was to assess in a large series of patients with a long-term clinical follow-up the validity of extracorporeal electromagnetic shock wave lithotripsy as a minimally invasive therapy for sialolithiasis. STUDY DESIGN: Consecutive patient series. METHODS: Three hundred twenty-two consecutive symptomatic outpatients with single or multiple calculi in the submandibular (234 patients) or parotid (88 patients) gland underwent a complete extracorporeal electromagnetic shock wave lithotripsy treatment. Treatment results were classified into three groups: successful result with complete ultrasonographic elimination of the stone after lithotripsy, successful result with residual ultrasonographic fragments that were less than 2 mm in diameter, and unsuccessful result with residual ultrasonographic fragments that were greater than 2 mm in diameter. Univariate and multivariate statistical analyses were performed. RESULTS: Complete elimination of the stone was achieved in 45% of patients. On ultrasonography, residual fragments (<2 mm in diameter) were detected in 27.3% of patients, and persisting fragments greater than 2 mm in diameter were assessed in 27.7% of patients. In 3.1% of patients, all with submandibular gland stones, sialoadenectomy was performed. Recurrence of calculi in the treated gland was observed during a median follow-up period of 57 months in four patients with complete ultrasonographic clearance of the stone occurring 10 to 58 months after lithotripsy. Univariate analysis showed that a favorable treatment result was significantly associated with the younger age of the patients (< or = 46 y), parotid and intraductal localization of the stone, diameter of the stone (< or = 7 mm), and number of therapeutic sessions (< or = 6). On multivariate analysis, the age of the patient, parotid site of the stone, stone diameter, number of therapeutic sessions, and number of shock waves were associated with favorable outcome. CONCLUSION: Extracorporeal electromagnetic shock wave lithotripsy is to be considered an efficient, minimally invasive treatment modality for salivary calculi.

Adolescent↗
PubMed2004

The use of shock wave lithotripsy for renal calculi.

PURPOSE OF REVIEW: Shock wave lithotripsy has been considered a mainstay of therapy for renal calculi for the last 20 years. Shock wave lithotripsy is noninvasive and requires the least anesthesia of the treatment modalities for treatment of renal calculi and therein lies its popularity. In the last decade, however, there have been changes in thinking regarding methods of patient selection for shock wave lithotripsy, changes in the technique of the existing shock wave lithotriptors and new technologies designed to increase the efficacy of shock wave lithotriptors. RECENT FINDINGS: New studies have shown that shock wave lithotripsy may be less effective than other modalities for treating lower pole stones. Other existing technologies, such as computerized tomography, are being used to more effectively select patients for shock wave lithotripsy. Ongoing studies are evaluating changing the shock wave rate to increase stone fragmentation. In addition, efforts are being made to improve lithotripsy by designing more effective lithotriptors. SUMMARY: Shock wave lithotripsy has become a widely used modality for treating renal calculi due to its noninvasive nature and ease of application. Although success rates are reasonable, there is room for improvement. With appropriate patient selection, significant improvements in stone-free rates may be achieved. It is anticipated that, with further research, improvements in lithotriptor design will result in higher treatment success rates with reduced renal trauma and improved patient comfort.

Equipment Design↗
PubMed2003

Extracorporeal shock wave lithotripsy for distal ureteral calculi: what a powerful machine can achieve.

PURPOSE: We assessed the efficacy of extracorporeal shock wave lithotripsy (ESWL, Dornier Medical Systems, Inc., Marietta, Georgia) for distal ureteral calculi with the HM3 (Dornier Medical Systems, Inc.) lithotriptor. MATERIALS AND METHODS: A total of 585 consecutive patients with distal ureteral calculi were treated with ESWL using an unmodified HM3 lithotriptor. Of these patients 67 referred for treatment only for whom no followup was available were excluded from further analysis. The remaining 518 cases were followed until they were radiologically documented to be stone-free or considered treatment failures. Before ESWL additional procedures were performed in 144 patients, including stone push back, ureteral catheter or Double-J (Medical Engineering Corp., New York, New York) stent placement, percutaneous nephrostomy, ureteral endoscopic maneuvers or stone basket manipulation. A total of 374 patients needed no preliminary treatment before ESWL. RESULTS: Of the 518 patients 469 (91%) were successfully treated with 1 ESWL session, while 49 (9%) needed 2 or 3. Manipulation after ESWL was performed in 22 cases, including stent placement, percutaneous nephrostomy, ureteral endoscopic stone removal and a stone basket procedure. On day 1 after ESWL 327 patients (63%) were stone-free, 158 (30%) had less than 5 mm. fragments and 33 (7%) had more than 5 mm. fragments. At 3 months the stone-free rate increased to 97%. CONCLUSIONS: These data show that ESWL for distal ureteral calculi with the powerful unmodified HM3 lithotriptor has a high success rate with a low rate of minimally traumatic manipulations before and after intervention. Results in terms of the re-treatment and stone-free rates are superior to those of any other second or third generation lithotriptor and comparable to the results of the best ureteroscopic series.

Adolescent↗
PubMed2004

Ex vivo ureteroscopic treatment of calculi in donor kidneys at renal transplantation.

PURPOSE: We evaluated the safety and efficacy of ex vivo ureteroscopy (ExURS) as a means of rendering the donated kidney stone-free at live donor renal transplantation. MATERIALS AND METHODS: A total of 10 suitable kidney donors with small, unilateral nonobstructive calculi underwent live donor nephrectomy (8 open flank, 2 hand assisted transperitoneal). Immediately after cold perfusion, ExURS was performed in an iced saline solution. Access to the collecting system was via the ureteral stump. Calculi were either removed with endoscopic baskets and/or completely fragmented with Holmium laser lithotripsy. RESULTS: Access to the renal collecting system was technically successful in all cases. A total of 10 stones, ranging in largest diameter from 1 to 8 mm (average 5.2) were visualized. Of the kidneys 6 had solitary stones, 2 had 2 stones and 1 had no stone. Of 10 stones 9 were successfully removed and/or fragmented with an average procedure time of 6.5 minutes (range 3 to 28). Indwelling ureteral stents were placed at transplantation in 5 of 10 kidneys. There were no intra-operative or postoperative ureteral complications. At 1 month after transplant serum creatinine ranged from 0.9 to 2.7 mg/dl (average 1.5). At a mean followup of 33.2 months new stones have not formed in any recipients and at mean 36.4-month followup no new calculi have formed in the remaining kidney of any donors. CONCLUSIONS: ExURS is a technically feasible means of rendering a stone bearing kidney stone-free without compromising ureteral integrity or renal allograft function.

Adolescent↗
PubMed2004

Bladder calculi after augmentation cystoplasty: risk factors and prevention strategies.

PURPOSE: Lower urinary tract reconstruction is an essential tool in the management of severely dysfunctional bladders in children. The incidence of calculi in augmented bladders has been reported in up to 50% of cases. We analyzed our experience with stone formation in this population to assess risk factors and outcomes. MATERIAL AND METHODS: We performed a retrospective cohort study of all patients who underwent bladder augmentation from 1988 to 2002 at our institution. Patient demographics, risk factors and management were abstracted from the medical record. RESULTS: A total of 105 patients (58 males and 47 females) were identified. Ileum, colon and stomach were used in 37, 18 and 50 patients, respectively. Median age was 8.0 years. Median followup was 8.4 years. A total of 12 patients (11%) were found to have bladder calculi. Ten patients with ileum (27%), 1 with colon (6%) and 1 with stomach (2%) formed stones. All patients had recurrent urinary tract infections. Nine patients were successfully treated with an endoscopic procedure. Four patients (33%) formed recurrent stones despite saline bladder irrigations. One patient had multiple recurrences but is now stone-free on a daily regimen of 20% urea instillation. CONCLUSIONS: Augmentation cystoplasty carries an overall low risk of bladder calculi. Gastrocystoplasty had a significantly lower rate of stone formation than augmentation with ileum and colon. Urinary tract infection is an independent risk factor for stone formation. Endoscopic management is safe and effective in the majority of patients and it may be facilitated by a percutaneous access. Recurrent stones form in some patients despite aggressive medical management.

Child↗
PubMed1991

Piezoelectric effect in renal calculi.

The piezoelectric effect is investigated for the first time in renal calculi in vitro. The kidney stones are shaped from solid samples as well as from stones crushed into powder and pressed into tablets. Presence of alpha quartz in the renal calculi is investigated by an X-ray technique and the presence of this constituent also helps to explain the piezoelectric effect in the renal calculi. The dielectric and piezoelectric parameters are studied in detail.

Electric Conductivity↗
PubMed1991

Comparative study of the role of endo-urological manipulation in the treatment of ureteric calculi using extracorporeal shock wave lithotripsy.

The results of treatment of 115 patients with upper and mid-ureteric calculi, using endo-urological manipulation and extracorporeal shock wave lithotripsy were reviewed. The number of shocks administered, the kilovoltage used, the radiation exposure time and the degree of fragmentation achieved were evaluated. Complications occurring in the course of this treatment were also reviewed. A significantly lower number of impulses was required for fragmentation to be apparent at 24 h post-treatment, when the ureteric calculus was able to be manipulated back into the renal pelvis. However, at 6 weeks post-extracorporeal shock wave lithotripsy (ESWL) satisfactory fragmentation was apparent in approximately equal percentages of patients who had undergone successful and unsuccessful manipulation. In addition, a significantly greater mean radiation exposure was used in the treatment of mid-ureteric calculi that could not be successfully manipulated and required treatment in situ within the ureter. These results suggest that treatment of a ureteric calculus in situ within the ureter provides a satisfactory method of fragmentation, although fragmentation takes longer to become apparent than when treatment is undertaken upon a calculus within the renal pelvis. The greater radiation exposure for patients in whom ureteric calculi were treated in in situ within the ureter may reflect the operators' attempts to visualize a change in configuration of the calculus similar to that seen when treatment is given to a stone that has been successfully manipulated. However, since the absence of fragmentation at 24 h post-surgery does not indicate a failed treatment in this group, prolonged screening of the calculus with fluoroscopy may be unnecessary. The complication rate of this method of treatment was low.

Adult↗
PubMed1992

Extracorporeal shock-wave lithotripsy for distal ureteric calculi.

The results of 67 consecutive patients referred to the New South Wales Lithotripter Centre with distal ureteric calculi were evaluated. All these patients were treated on the Dornier HM3 Lithotripter. Distal ureteric calculi were classified as those at, or distal to, the proximal margin of the sacro-iliac joint. Eleven patients with stones overlying the sacro-iliac joint were treated in the prone position, while 56 patients with stones distal to the sacro-iliac joint, were treated in the saddle (astride) position. Of the 64 patients in whom follow-up was available, 44 (69%) were rendered totally stone free by extracorporeal shock-wave lithotripsy (ESWL). Lithotripsy has proved an effective treatment for distal ureteric calculi and has rendered 69% of patients stone free with minimal morbidity. Stones overlying the sacro-iliac joint can be successfully treated in the prone position.

Adult↗
PubMed1982

Urinary calculi in children. A 5 to 15-year follow-up with particular reference to recurrent and residual stones.

Between 1965 and 1974 188 children were operated on for urinary calculi; 150 cases of non-metabolic stones have been followed up for 5 to 15 years to assess the results of surgery and to evaluate recurrent and residual calculi. Of 132 cases completely cleared of stones at initial surgery 11 had a recurrence; 8 of the recurrences developed amongst 33 patients who remained persistently infected post-operatively. Reoperation was necessary in 8 cases to stop renal deterioration. Amongst 18 patients with residual calculi only 7 required reoperation; small residual fragments were effectively controlled with long-term antibiotic therapy and close supervision.

Child↗
PubMed1988

Analysis of magnesium and trace elements in urinary calculi by atomic absorption spectrophotometry.

Magnesium and trace element determinations in 29 urinary tract calculi were carried out using an atomic absorption spectrophotometric method. Of the calculi examined, 9 were pure calcium oxalate, 5 were mixed calcium oxalate/uric acid, 5 were mixed calcium oxalate/phosphate, 5 were magnesium ammonium phosphate and 5 were pure cystine. The measurement of magnesium and trace element levels has been considered useful in the elucidation of the mechanism of stone formation and the evaluation of factors leading to pathological consequences. In this study, the Mg, Zn, Cu, Fe, Cd and Pb content in all of the samples was determined and an attempt was made to compare the levels of these elements in calculi with the levels in normal hair.

Humans↗
PubMed1990

Staghorn calculi of the kidney: classification and therapy.

Following the introduction of new techniques, the reclassification of staghorn calculi is indicated in order to establish the most suitable form of treatment. Of 269 patients with staghorn calculi treated over a 3-year period, 56% underwent extracorporeal shockwave lithotripsy (ESWL) monotherapy; 16% required open surgery and the remaining 28% underwent percutaneous nephrolithotripsy (PCNL) with ultrasound in association with ESWL. The latter group has been reviewed, taking into account invasiveness, results, complications and cost effectiveness. A combination of PCNL and ESWL was beneficial in patients in whom percutaneous access through a single tract removed more than 70% of the stone. As a result of these findings, the authors propose a revised classification of staghorn calculi.

Adolescent↗
PubMed1994

Laparoscopic ureterolithotomy: the results of an initial series, and an evaluation of its role in the management of ureteric calculi.

OBJECTIVE: To evaluate the place of laparoscopic ureterolithotomy in the management of ureteric calculi for which extracorporeal shockwave lithotripsy (ESWL) and endourological techniques are unsuitable. PATIENTS AND METHODS: Laparoscopic ureterolithotomy was attempted in nine patients (eight men, one woman) with an age range of 26-81 years (mean 55.5) who had large, long standing and impacted calculi in the upper and mid ureter. The stone size ranged from 5 to 28 mm (mean 13.2) and stone duration ranged from one to 24 months (mean 8.2). The transperitoneal route was used in six patients and the extraperitoneal route in three but was converted to a transperitoneal approach in two. RESULTS: The stone was successfully removed in all nine patients. The operative time ranged from 80 to 260 minutes (mean 158). No intra-operative complication was encountered and no patient required a blood transfusion. Post-operative complications included urinary leak and fever. The post-operative stay ranged from 2 to 13 days (mean 5.2). CONCLUSIONS: Laparoscopic ureterolithotomy has definite advantages over open ureterolithotomy. Furthermore, the more difficult a stone is for treatment by ESWL and endourological techniques, the more suitable it is for laparoscopic removal. For large, hard, long-standing and impacted ureteric calculi, one laparoscopic ureterolithotomy as initial therapy may be preferable to multiple endourological and ESWL procedures.

Adult↗
PubMed2004

Urodynamic findings before and after noninvasive management of bladder calculi.

OBJECTIVES: To determine the most frequent urodynamic observations associated with bladder calculi, and to assess whether the presence of calculi alters these observations. PATIENTS AND METHODS: Fifty patients with bladder stones were included in a prospective study in which two urodynamic tests were used, one at inclusion and another once the patient was stone- free after treatment by noninvasive methods (mainly extracorporeal shockwave lithotripsy). RESULTS: The results from the urodynamic evaluation with the stone in the bladder were: bladder outlet obstruction in 51%, detrusor overactivity in 68%, detrusor under-activity in 10%, and a normal study in 18%. There were no significant differences between the urodynamic study before or after treatment in maximum flow rate and postvoid residual volume, detrusor overactivity and detrusor pressure at maximum flow. CONCLUSIONS: Conversely to what has been accepted for years, bladder calculi are not always associated with bladder outlet obstruction and the urodynamic results are not influenced by the presence of bladder stones during the urodynamic testing.

Aged↗
PubMed2002

The modulus of toughness of urinary calculi.

To improve the efficacy of extracorporeal shock wave lithotripsy (ESWL) treatment, it is desirable to identify the physical properties of urinary calculi could offer direct correlation with their fragilities during ESWL and thus could be used to guide treatment procedures for more effective stone fragmentation. Thirty stone specimens removed surgically were compressed by an axial testing system to measure the compressive strength and trace the stress-strain curve. Image analysis software SigmaScan (Jandel Co.) was used to calculate the area under the stress-strain curve, the modulus of toughness, for each stone. The values of compressive strength measured were similar to those reported by other researchers. The modulus of toughness of urinary calculi correlates with clinical representation of the stone fragility during ESWL. The modulus of toughness could be an index to evaluate the physical property of urinary calculi that could be used to guide treatment procedures for more effective stone fragmentation.

Compressive Strength↗
PubMed1967

Siliceous urinary calculi in calves: prevention by addition of sodium chloride to the diet.

Urinary calculi were found in all but one of 14 calves given a ration associated with the formation of siliceous calculi. No calculi were found in a similar group of 14 calves given the same ration with sodium chloride added (4 percent). It is suggested that sodium chloride prevented calculus formation by in creasing water intake and urine volume, with a consequent reduction in the con-centration of silicic acid in the urine

Animals↗