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PubMed1990

The effect of extracorporeal shock wave lithotripsy on the microbiological flora of urinary calculi.

To determine whether extracorporeal shock wave lithotripsy can sterilize infection stones and, thus, decrease the recurrence rate we investigated its impact on the microbiological flora of staghorn calculi. Fragments from 17 staghorn calculi retrieved percutaneously were divided into paired sets. One set was fractured by extracorporeal shock wave lithotripsy at 18 kv. and with increasing numbers of shock waves up to 1,000. One set was fractured mechanically with a surgical clamp. Bacterial cultures were then compared between the 2 groups. Of the 17 staghorn calculi 10 showed significant bacterial growth (59%). The number of colony-forming units was not significantly different between stones fragmented by lithotripsy and those that were mechanically fractured. Furthermore, exposing fragments to an increasing number of shock waves did not alter the colony count. We conclude that extracorporeal shock wave lithotripsy has no discernible effect on the microbiological flora of infected staghorn calculi.

Colony Count, Microbial↗
PubMed1988

Ureteropyeloscopic removal of ureteral calculi.

Ureteroscopy has been used for the treatment of calculi throughout the ureter. The results of ureteroscopic stone removal were reviewed in 100 patients. Similar results were compared in 30 patients undergoing ureterolithotomy and 32 treated by basket manipulation. Success of ureteroscopic removal was related to the location of the calculus: 50 per cent in the proximal, 80 per cent in the mid and 99 per cent in the distal ureter. Hospital stay, costs and narcotic analgesic use were significantly less for ureteroscopic stone removal than for open surgical lithotomy. The success rate for ureteroscopic removal of distal calculi (99 per cent) was higher than for blind basketing procedures (59 per cent). Ureteroscopy should be considered the technique of choice for the removal of distal ureteral calculi. It is an acceptable alternative for treatment of calculi throughout the urinary tract.

Adult↗
PubMed1986

Crystal-matrix interrelations in brushite and uric acid calculi.

Brushite and uric acid calculi were studied by means of scanning electron microscopy with the partial dissolution method and transmission electron microscopy. Brushite calculi consist of radially oriented columnar crystals which have sheet-like substructure. The organic matrix is identified chiefly at the outside of the crystals but partly included between the substructure. The concentric matrix bands are often dislocated between the neighbouring crystals. Uric acid calculi also consist of radially oriented columnar crystals, and a fine meshwork of the organic matrix is incorporated within the crystals. The concentric matrix layers of different density are angled according to the crystal lattice. These findings indicate that the organic matrix arose from a mucinous surface coat, at least in the radially striated calculi. The crystals continued to grow in this gel-state milieu, either thrusting the matrix aside or incorporating it within the crystals.

Calcium Oxalate↗
PubMed1986

Caliceal calculi.

Primary nonobstructive caliceal calculi were removed by nephrostolithotomy in 51 patients. Among the patients with caliceal stones indications for removal included pain in 36 (71 per cent), associated infection in 11 (21 per cent), progressive stone growth in 2 (4 per cent), hematuria in 1 (2 per cent) and flight status eligibility in 1 (2 per cent). Over-all, 300 patients have undergone percutaneous removal of upper urinary tract calculi, with a 97 per cent success rate. Successful removal was completed percutaneously in 49 patients (96 per cent). One patient remains asymptomatic with retained caliceal fragments and surgical stone removal was required in 1 additional patient. Complications occurred in 4 patients (8 per cent). One patient underwent transcatheter embolization of an intralobar artery to control renal bleeding. Three patients required placement of an internal Double-J ureteral stent to permit resolution of ureteral edema. Following recovery 34 of 36 patients (95 per cent) reported complete resolution of the preoperative pain for which the calculus was removed. Two patients had persistent urinary infection. The remaining patients reported no residual complaints. These observations suggest that pain and discomfort occasionally may be associated with nonobstructive caliceal calculi. Removal of caliceal calculi may permit resolution of associated discomfort in more than 90 per cent of all carefully selected patients.

Adult↗
PubMed1985

Architecture of calcium oxalate monohydrate urinary calculi.

We have developed a partial dissolution method which enabled us to observe the internal architecture of urinary calculi. Using this method with improved organic matrix fixative, we studied the architecture of small calcium oxalate monohydrate urinary calculi with special attention to crystal-matrix interrelations. Calculi, we have observed, are invariably composed of 3 distinct zones. A core area is composed of randomly aggregated plate-like crystals with tendency of rosette formation. This core area is surrounded by an intermediate layer which shows prominent radial striations. This layer is composed of radially arranged piles of sheet-like crystals which extend beyond many layers of lamination. This layer gradually shifts to a peripheral layer where concentric laminations are prominent and each layer of lamination is composed of minute crystals which have lost radial arrangement. The organic matrix is observed only at the outside of the crystals, and matrix-rich crystal-poor bands separate each layer of concentric lamination. The concentric lamination seems to be a manifestation of the altered density of organic matrix which encrusted on the developing calculi and offered a milieu for crystal growth within.

Calcium Oxalate↗
PubMed1984

Bacteriology of branched renal calculi and accompanying urinary tract infection.

We determined the bacteriology of apparently infected renal calculi and accompanying urinary tract infections, and assessed the potential clinical value of the culture results. Twenty-two branched renal calculi from 16 patients were cultured. Fifteen calculi were infected with 1 or more urease-producing gram-negative enteric bacterium, 2 were infected with a urease-producing bacterium and a nonurease-producing organism, and 5 were sterile. Immersion of infected stones in antimicrobial solutions before culture reduced or eliminated surface bacteria but usually did not eradicate bacteria within the stone. The bacteriology of a stone or stones could be predicted on the basis of available urine culture results in only 2 of the 16 cases. These data suggest that branched renal calculi associated with bacteriuria usually are infected but that documentation of infection and identification of the infecting organism require culture of the stone.

Anti-Bacterial Agents↗
PubMed1983

Xanthine calculi in the Lesch-Nyhan syndrome.

Urinary tract calculi composed primarily of xanthine are rare in adults and children. However, there is risk of xanthine calculi formation in children with hereditary xanthinuria and children on xanthine oxidase inhibitor therapy for hyperuricemia. We describe the clinical presentation and management of 2 children with the Lesch-Nyhan syndrome (a congenital disorder of purine metabolism) and xanthine calculi. Little information has been available to direct the urologic management of such patients. We have based a plan for management upon our clinical experience with these children, as well as upon in vitro dissolution studies of the calculi. We have had some clinical success using an alternating acid/base dissolution therapy developed in the laboratory.

Adolescent↗
PubMed1982

Renal calculi associated with incomplete distal renal tubular acidosis.

We report 5 cases of renal calculi associated with incomplete type I renal tubular acidosis. The patients presented with a history of recurrent calculi and demonstrated bilateral calculi with corticomedullary junction calcification on x-ray. Stone analysis revealed primarily calcium phosphate stones and metabolic studies demonstrated hypercalciuria, mild depression of serum bicarbonate and inability to lower the pH of a fasting morning urine to less than 5.8. The 24-hour urinary citrate excretion was depressed markedly. The diagnosis was confirmed by an ammonium chloride loading test. Treatment consisted of alkalization of the patients, which corrects the hypercalciuria and increases the urinary citrate level and should decrease the tendency to form stones. The diagnosis of incomplete type I renal tubular acidosis should be considered in patients with recurrent renal calculi.

Acidosis, Renal Tubular↗
PubMed1982

Observations on lower urinary tract calculi in children.

Lower urinary tract calculi are rare in American children. In 20 years 26 children with bladder or urethral stones have been treated. Boys outnumbered girls by 3 to 1. All patients had urinary tract infection. Most patients harbored phosphatic calculi and had urinary tract anomalies or neurogenic dysfunction. Calculi were managed surgically in 25 children. Only 2 children suffered from recurrent vesical calculi.

Child↗
PubMed1981

Intraoperative roentgenography in the surgical removal of renal calculi.

Complete surgical removal of staghorn or multiple renal calculi is extremely difficult. Intraoperative roentgenography has been used to decrease the incidence of residual calculi. We herein assess the effectiveness of intraoperative roentgenography and emphasize important operative technical aspects. Between 1973 and 1979, 42 patients underwent 50 operations for the removal of staghorn or multiple renal calculi. Intraoperative roentgenography was used in 47 operations and omitted in 3. Of the 47 operations done with intraoperative roentgenography 31 units were free of stones and 12 had small retained fragments known intraoperatively with verification by postoperative tomography or plain abdominal film. In 1 case of calculus recognized intraoperatively passed during the postoperative period and tomograms demonstrated no residual calculi. Only 3 patients had residual stones postoperatively with negative intraoperative films. The 3 patients who did not have intraoperative roentgenography all had residual fragments. All 3 kidneys were thought to be free of residual stones as determined by visual inspection and nephroscopy. With the aid of intraoperative roentgenography the incidence of residual stones was 23 per cent. Followup for up to 6 years in 45 renal units showed 73 per cent to be free of stones. When properly used intraoperative roentgenography is highly accurate. Films should be obtained before any stones are removed and care should be taken to x-ray the entire kidney even if 2 films are required. Final films should be obtained after all fragments are removed.

Humans↗
PubMed2000

Bladder calculi in augmentation cystoplasty in children.

OBJECTIVES: To determine the best preventive strategies for bladder calculi in children with an augmented bladder, the risk factors and prevention strategies for urolithiasis were evaluated. METHODS: The records of 89 patients following augmentation cystoplasty were reviewed to assess the results of augmentation cystoplasties and in particular the formation and prevention of calculi. RESULTS: The median follow-up was 4.9 years after augmentation. Most patients (71) had an ileocystoplasty. Bladder calculi occurred in 14 of the 89 patients (16%) and recurred in 4 patients. Girls had a higher incidence of urolithiasis. Other risk factors were cloacal malformations, vaginal reconstructions, anal atresia, clean intermittent catheterization problems and retention, bladder neck surgery, and symptomatic urinary tract infections. CONCLUSIONS: Subgroups with cloacal malformations, vaginal reconstructions, ureter reimplantation, and bladder neck surgery were identified that have an increased risk for stone formation and therefore warrant special care in the follow-up after augmentation. This care should include clear emphasis on the role of treating symptomatic urinary tract infections, especially in patients with cloacal malformations and vaginal reconstructions. Girls have a higher incidence of bladder calculi than boys.

Adolescent↗
PubMed1996

Urethroscopy in small neonates with posterior urethral valves and ureteroscopy in children with ureteral calculi.

OBJECTIVES: To describe our recent experience using a 6.9F cytoscope in the fulguration of posterior urethral valves (PUVs) in premature neonates and distal ureteroscopy with stone extraction in children. METHODS: Fulguration of PUVs was performed in 3 premature neonates born at 34 to 36 weeks' gestation with weights of 2480 to 2900 g. The PUVs were fulgurated during a single endoscopic procedure using a 6.9F cystoscope and a 3F bugbie electrode. In addition, 11 children (8 girls, 3 boys; mean age, 11.1 years; range 5 to 16) with symptomatic calculi underwent 15 distal ureteroscopic procedures using the 6.9F cystoscope. RESULTS: In the neonates with fulguration of PUVs, vesicostomy, the only reasonable alternative, was avoided, and each infant now voids with an excellent stream 3 to 16 months later, without evidence of stricture or residual valves. In the children with distal ureteroscopy, the ureteral calculi were retrieved using a 3F four-wire stone basket. With one exception, distal ureteroscopy was performed without dilation of the ureteral orifice. Extracorporeal shock-wave lithotripsy (ESWL) was not recommended because of stone position and difficult radiographic visualization. Nine children were rendered stone free with one procedure. Two procedures were required in 1 child and three in another. In both cases, ureteral edema was present, and the stone was embedded in the ureteral wall. One child underwent separate procedures for bilateral calculi. In all cases general anesthesia was used, with a mean duration of 63 minutes (range 28 to 96). Temporary ureteral stenting was performed in 10 (93%) patients, and 9 (81%) were discharged home on the same day or the next morning. A mean follow-up period of 8.5 months (range, 0.5 to 22) has failed to show any problems related to ureteral stricture or injury. CONCLUSIONS: Endoscopic fulguration of PUVs is now possible in small neonates and is minimally invasive compared with vesicostomy. Distal ureteroscopy with stone retrieval should be considered in children, especially those with calculi that are not suitable for ESWL.

Adolescent↗
PubMed1997

Spiral computed tomography for staghorn calculi.

OBJECTIVES: To assess the utility of spiral computed tomography (CT) with three-dimensional reconstruction for preoperative planning of percutaneous nephrostolithotomy in patients with complex branched calculi (full staghorns). METHODS: Patients with complex branched stones were imaged with spiral CT with three-dimensional reconstruction. These images were compared with standard imaging modalities, including excretory urography and plain radiographs, for planning percutaneous access for nephrostolithotomy. The utility of the scan was evaluated. RESULTS: Ten patients with branched calculi were studied. Anatomic abnormalities were present in 5 patients. Excellent three-dimensional images were obtained in all patients without any complications related to the study. In 1 patient with multiple calculi in a horseshoe kidney, the three-dimensional image indicated a branched stone. The spiral CT scan was not helpful in directing percutaneous access in any patient. In a single patient, residual fragments noted during nephrostolithotomy were located by reference to the spiral CT scan. CONCLUSIONS: Spiral CT scans with three-dimensional reconstruction provide three-dimensional imaging of branched renal calculi. This modality provides minimal additional information over that obtained from standard radiographic studies for guiding nephrostolithotomy and cannot be recommended as a routine preoperative study. It was helpful in 1 patient to locate a residual fragment.

Adult↗
PubMed1999

Nonsurgical management of infection-related renal calculi.

Struvite calculi can be a debilitating affliction for which the cure is mainly surgical. If left untreated, infection-related calculi can cause failure to thrive, anemia, chronic renal insufficiency, renal failure and death. There has been much research aimed at non-surgical intervention and prevention of these calculi especially in this "non-invasive" era. The historic and current non-surgical treatment modalities of struvite calculi are discussed.

Humans↗
PubMed1985

Usefulness of abdominal flat plate radiographs in patients with suspected ureteral calculi.

A total of 120 plain abdominal radiographs (PARs) from intravenous pyelograms (IVPs) were presented without patient history in a random manner to a staff radiologist and staff emergency physician (EP). Scout films were used as the PAR to minimize calculus movement. Each reader examined each film for the presence of ureteral calculi. The readers localized all calculi and rated the likelihood of their presence. Fifty-one PARs from IVPs demonstrated ureteral calculus disease; 40 of these films demonstrated 41 radiopaque calculi, while 11 films demonstrated obstruction without radiopaque calculi. These readings were then matched to the known IVP results. Together the readers were correct on 50% of the predictions (radiologist, 51%; EP, 48%). The EP and the radiologist had similarly correct percentages on PARs from positive IVPs (33% and 36%, respectively) and on PARs from negative IVPs (60% and 64%). True-positive (33% and 25%), true-negative (76% and 71%), false-positive (27% and 35%), and false-negative (36% and 55%) rates were constructed for the radiologist and EP, respectively. Our study demonstrates that PARs are unreliable and do not appear to add useful information in the evaluation of suspected ureteral colic.

Diagnostic Errors↗
PubMed2006

[Unusual elements in renal calculi].

A group of 54 renal calculi were spontaneously passed renal stone after a nephritic colic. Two groups of calculi were found: papillary and non-papillary calculi. All calculi were analyzed by infrared spectroscopy and electronic microscopy scan (EMS) and EDAX. When the stones were analyzed with EDAX, elements such as C, N, O, Na, S, Mg, Al, Si, Cl, K, Ca, Mn, Fe, Ni, Zn were detected. The possible origin of these elements is discussed in this work.

Humans↗
PubMed2003

Utility of the lithoclast in the treatment of upper, middle and lower ureteric calculi.

OBJECTIVE: The aim of this study was to evaluate the utility and efficacy of lithoclast in the treatment of upper, middle and lower ureteric calculi. PATIENTS AND METHODS: Over a period of 6 1/2 years, we have treated 529 ureteric stones which failed to pass spontaneously within a 2-week period. Patients were evaluated for number, site, size and laterality of stones. Patients with ureteroscopy failure were excluded from the study. Once the stone(s) was (were) localised with the ureteroscope, it (they) was (were) treated with the Swiss lithoclast. RESULTS: Complete fragmentation was achieved in 99% of cases with lower, 97% with mid and 71% with upper ureteric calculi, respectively. The lithotripsy time was only 8.6 minutes for stones < or =1 cm and 14.8 minutes for stones ranging from 1.1 to 2.0 cm. Completely fragmented stones cleared spontaneously within two weeks in 98% of cases and all patients were free of calculi one month after the procedure. Retreatment with the lithoclast was required in six patients for large residual fragments. The mean hospital stay was 1.2 days. Complications were encountered in 6.8% of cases and were managed conservatively. CONCLUSIONS: Pneumatic lithotripsy is an excellent form of treatment for lower and mid-ureteric calculi. It is a very reliable, highly effective, rapid and safe procedure.

Adolescent↗
PubMed1998

Treatment of mid- and lower ureteric calculi: extracorporeal shock-wave lithotripsy vs laser ureteroscopy. A comparison of costs, morbidity and effectiveness.

OBJECTIVES: To determine the efficacy and costs of extracorporeal shock-wave lithotripsy (ESWL) compared with ureteroscopy (URS) in the treatment of mid- and lower ureteric calculi. PATIENTS AND METHODS: The records of patients treated primarily by ESWL and URS were analysed retrospectively. Treatment with ESWL included 63 patients (42 men and 21 women, mean age 52 years, range 23-78, 19 mid- and 44 lower ureteric calculi). All patients received 4000 shock waves at a mean energy setting of 18.1 kV. URS was used in 105 patients, with a 7.2 F miniscope or the 7.1 F flexible scope. Stones were fragmented with a pulsed-dye laser lithotripter at 504 nm and a power of up to 130 mJ (mean 53 mJ) using a 200 or 320 microns fibre. All ureteroscopies were performed with the patient under general (n = 17) or spinal (n = 87) anaesthesia in a mean treatment duration of 34 min. Stones were located in the mid-ureter in 24 patients and in the lower ureter in 80. The outcome was assessed by stone-free rates, re-treatment rates, time to become stone-free, complication and costs. RESULTS: ESWL for mid- and lower ureteric calculi resulted in a success rate of 90% and 81%, respectively, compared with 96% and 99% for URS. However, patients treated with URS were stone-free within 2 days, whereas patients in the ESWL group required up to 4 months. The best results for ESWL were achieved with stones of < 50 mm2. The costs of URS were higher than those for ESWL. CONCLUSIONS: ESWL provides a noninvasive, simple and safe option for the management of mid- and lower ureteric calculi, provided that the stones are < 50 mm2; larger stones are best treated by URS.

Adolescent↗