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PubMed1995

Washington University experience with extracorporeal shock-wave lithotripsy of pancreatic duct calculi.

OBJECTIVES: To ascertain the effectiveness and safety of extracorporeal shock-wave lithotripsy (ESWL) for pancreatic calculi. METHODS: Fourteen ESWL treatments were performed in 12 patients with chronic pancreatitis. RESULTS: Fragmentation was perceptible after 13 of 14 treatments. Subsequent endoscopic manipulation resulted in complete extraction, partial extraction, and failed extraction of the fragments after 7, 4, and 2 of the ESWL treatments, respectively. No complications occurred and no patient had pancreatitis following ESWL. At a median follow-up of 19 to 22 months, 4 patients have had complete relief of symptoms, 4 have had a decrease in both severity and frequency of pain, and 4 have had no improvement. CONCLUSIONS: ESWL is a safe and useful noninvasive adjunct in the treatment of patients with pancreatic duct calculi.

Adult↗
PubMed2005

[Porphyrins in renal calculi (review)].

We performed a review of the porphyrines content in a type of black, charcoal-like, renal calculi exhibiting infrared spectra (IRS) similar to those characteristic of "organic material" which has not yet been fully elucidate. Several other types of renal calculi, mainly those of small size, spontaneous passage renal stone, may also have diffuse or isolated dark charcoal components showing "organic material" IRS. After observing that haemoglobin has an "organic material" IRS, we studied, by a sensitive thin layer chromatography method, the presence of porphyrines in several types of dark or charcoal renal stones, since porphyrines are the physiological precursors of haemo group biosynthesis. We found two types of porphyrine content: coproporphyrin, in patients suffering from hepatopathy, and uroporphyrin and heptacarboxil-porphyrin in patients with some types of porphyria or with chronic renal failure.

Humans↗
PubMed2002

Urinary tract calculi and thresholds in carcinogenesis.

Numerous chemicals administered to rodents at relatively high doses produce urinary tract calculi, resulting in erosions or ulcerations of the urothelium, consequent regenerative hyperplasia, and ultimately tumors. This is a high-dose (threshold) phenomenon, which appears to occur more readily in rodents than in primates, including humans. Several anatomic and urinary physiologic differences between rodents and humans affect the quantitative extrapolation from results in rodent bioassays to human risk assessment. For most chemicals producing tumors by this mode of action, human exposures are significantly lower than would be expected to be required for production of calculi, and therefore pose no carcinogenic hazard to humans.

Animals↗
PubMed2001

Correction of helical CT attenuation values with wide beam collimation: in vitro test with urinary calculi.

RATIONALE AND OBJECTIVES: Urinary calculi are now commonly detected with helical computed tomography (CT), and it has been proposed that stone composition can be determined from CT attenuation values. However, typical scans are made with a beam collimation of 5 mm or more, resulting in volume averaging and reduction in accuracy of attenuation measurement. The authors tested a model for correction of errors in attenuation values, even at section widths larger than the width of the object. MATERIALS AND METHODS: Human urinary stones were scanned with helical CT at different beam collimation widths. A computer model was used to predict the effect of beam width and stone size on accuracy of measured attenuation. RESULTS: At 3-mm collimation, the model corrected the attenuation readings with an underestimation of 12% +/- 1 (compared with values at 1-mm collimation; 127 stones; diameters of 1.7-11.3 mm). With attenuation measured at 10-mm collimation, the model underestimated the true value by 34% +/- 3 (103 stones), with a significant negative correlation with stone diameter on magnitude of error (diameters of 3.0-11.3 mm). Correlation of data from patient scans with subsequent in vitro scanning of the same stones confirmed the validity of the model, but corrected in vivo scans consistently yielded lower values for the stones than in vitro. CONCLUSION: Volume averaging effects on attenuation in helical CT are predictable in vitro for urinary calculi--and presumably for other roughly spherical structures--as long as section width does not excessively exceed the diameter of the structure.

Computer Simulation↗
PubMed2001

Effect of radiographic contrast material exposure on spiral CT attenuation of renal calculi.

RATIONALE AND OBJECTIVES: The authors performed this study to determine whether exposure of renal calculi to radiographic contrast material has an effect on the attenuation values at computed tomography (CT) performed with varying collimation widths. MATERIALS AND METHODS: Renal calculi (23 stones of various composition) were scanned with 1-, 3-, and 10-mm collimation. Stones were then exposed to a solution of radiographic contrast material for 5 minutes, washed with water, and rescanned 36 hours later. The reproducibility of the CT attenuation measurements on different days was evaluated by obtaining measurements in a subset of 16 renal stones on 4 different days. RESULTS: There was no statistically significant change in attenuation after contrast material exposure at narrow collimation. At wider collimation, statistically significant increases were noted in both attenuation and standard deviation. A small amount of variability between readings was noted on different days, with a minimal increase in attenuation each day. Correlation between readings remained very high. CONCLUSION: Exposure of stones to a radiographic contrast material had a statistically significant effect on CT attenuation values only at wide collimation. This may be related to technical factors including volume averaging. Absence of an effect at narrow collimation suggests that the attenuation values of renal stones do not significantly change after exposure to contrast material.

Contrast Media↗
PubMed2004

An audit of 2273 ureteroscopies--a focus on intra-operative complications to justify proactive management of ureteric calculi.

BACKGROUND: At the national Stone Centre we have adopted a proactive management approach involving early ureteroscopy for ureteric calculi. As the efficacy of ureteroscopy is known this study focuses on the low intra-operative complication rate as justification for a proactive management protocol. PATIENTS AND METHODS: A retrospective study (1987-1997) identified 1936 patients undergoing 2273 ureteroscopies. A database was created from inpatient hospital records. The male to female ratio was 3 to 1, age range was 25 to 84 years. RESULTS: Twenty-three patients (1%) had an intra-operative complication during ureteroscopy. Immediate ureteric JJ stenting was performed in 16 cases with ureteric injury. Two cases underwent percutaneous drainage and delayed antegrade ureteric stenting, ureteroscopy was terminated because of poor visibility. Five patients (0.22%) underwent open surgery for: ureteric perforation (n = 2); Dormia basket ureteric avulsion (n = 1); impacted Dormia basket and stone (n = 1); and impacted balloon dilator and stone (n = l). Ureteroscopic complications were not related to the level of ureteric calculus. CONCLUSION: A protocol of proactive management of ureteric calculi facilitates rapid turnover of large patient numbers. This approach is supported by the low intra-operative complication rate, most of which can be managed by further endoscopic procedures. In the event of corrective open surgery a favourable outcome has resulted.

Adult↗
PubMed2006

Hair as the nidus for bladder calculi formation complicating suprapubic cystostomy catheterization: a case report.

Neurogenic bladder is a familiar sequel to spinal cord injury, and bladder calculi is a common complication of neurogenic bladder. We report a case of a 25-year-old man with spinal cord injury resulting in neurogenic bladder. Permanent cystostomy was performed, and, for 4 years, the patient received periodic replacement of a cystostomy catheter. Bladder calculi were found on follow-up radiography. Cystoscopic lithotripsy was done, and it was noted that a hair was the nidus of a calculus. The hair could have been introduced into the bladder accidentally during the cystostomy catheter replacement. We suggest routine pubic hair care, even shaving, for patients suffering from neurogenic bladder with cystostomy. In addition, patients and caregivers should take care not to introduce pubic hair into the bladder while changing cystostomy catheters.

Adult↗
PubMed2001

Acute renal failure due to bilateral matrix renal calculi--a diagnostic dilemma.

We report an unusual case of acute renal failure caused by bilateral matrix calculi. The difficulties in diagnosing the cause of renal failure and the management of the case are discussed. Matrix calculi are rare causes of acute renal failure. Being radiolucent they can be elusive and systematic investigation and a diligent search are required for correct diagnosis and appropriate treatment.

Acute Kidney Injury↗
PubMed1983

Infrared spectrometry and Raman microprobe in the analysis of urinary calculi.

Infrared spectrophotometry and Raman spectroscopy, thanks to the laser molecular microsond (MOLE), are two analytical techniques particularly well suited to a precise analysis of the composition and structure of urinary calculi. They both showed noteworthy efficiency in their ability to recognize the various crystalline or amorphous mineral and organic species. The MOLE permits analysis of crystals 1 mu in size, demonstrating its usefulness in the study of calculi nuclei as well as in the study of urinary crystals. These analyses are a very important source of information about conditions of crystalline nucleation and growth as well as about ions and molecules which can take place in the formation and the evolution of the diverse crystalline phases. On the clinical level, these data can contribute to a better comprehension of the formation of every stone.

Apatites↗
PubMed1995

The management of upper urinary tract calculi by piezoelectric extracorporeal shock wave lithotripsy in spinal cord injury patients.

From May 1988 to September 1994, 15 spinal cord injury patients were treated by piezoelectric extracorporeal shock wave lithotripsy. Aged from 23 to 71 years (mean = 39), they presented with a total of 23 stones, of which 18 were located in the calyces, three in the renal pelvis and two in the proximal ureter. The maximum dimensions of calculi varied from 5 to 35 mm (mean = 11). Patients were placed in a dorsal decubitus position during the sessions, three being sedated with diazepam, while the other 12 remained unsedated. All were treated routinely with systemic antibiotics. Auxiliary procedures consisted of two pyelocalyceal flushings, three double J ureteral stenting and three ureteroscopies with fragment removal with a Dormia basket. No episode of autonomic dysreflexia was observed. Short term side effects were limited to a few cases of gross haematuria which regressed spontaneously. Overall, eight successes (53%), and seven failures (47%), were registered. Of the failures, one was the result of a partial fragmentation, while six were related to intrarenal retention of residual fragments resulting in four cases in rapid recurrences. Extracorporeal shock wave lithotripsy can be easily applied to spinal cord injury patients. Its usefulness and limitations need to be well understood and a global consideration must be applied to the prevention and early detection of the upper urinary calculi in this exposed population of patients.

Adult↗
PubMed1999

Spontaneous expulsion of large vesicle calculi in a woman with paraparesis.

INTRODUCTION: Urolithiasis is a common but preventable complication of Spinal Cord Disorders (SCD). CASE REPORT: We report a 25-year-old woman with paraparesis who spontaneously passed two large calculi perurethra without pain and developed urethral scarring. Detrusor hyperreflexia, absence of sensations and lack of sphincter tone could have contributed to painless expulsion of the large calculi in this patient. CONCLUSION: Dysuria, a prominent symptom of urolithiasis may not be present in subjects with SCD. Awareness about urolithiasis among health professionals involved in the care of SCD patients is necessary for prevention and early intervention.

Adult↗
PubMed2004

Calculus anuria in a spina bifida patient, who had solitary functioning kidney and recurrent renal calculi.

STUDY DESIGN: Clinical case report with comments by colleagues from Austria, Belgium, Germany, Japan, and Poland. OBJECTIVES: To discuss challenges in the management of spinal bifida patients, who have marked kyphoscoliosis and no vascular access. SETTING: Regional Spinal Injuries Centre, Southport, UK. METHODS: A female patient, who was born with spina bifida, paraplegia and solitary right kidney, had undergone ileal loop urinary diversion. Renal calculi were noted in 1986. Percutaneous nephrostolithotomy was performed in 1989 and there was no residual stone fragment. However, she developed recurrence of calculi in the lower pole of the right kidney in 1991. Intravenous urography, performed in 1995, revealed right staghorn calculus and hydronephrosis. Chest X-ray showed markedly restricted lung volume due to severe kyphoscoliosis. In 2000, she was declared unsuitable for anaesthesia due to a lack of venous access and a high likelihood of difficulty in weaning off the ventilator in the postoperative period. In June 2002, she developed anuria (urine output=18 ml/24 h) due to ball-valve-type obstruction by a renal stone at the ureteropelvic junction. Urea: 14.4 mmol/l; creatinine: 236 microl/l. Ultrasound showed right hydronephrosis. Percutaneous nephrostomy was performed. RESULTS: Following relief of urinary tract obstruction, there was postobstructive diuresis (3765 ml/24 h). However, the patient expired 19 days later due to progressive respiratory failure. CONCLUSION: In this spina bifida patient, who had reached the age of 35 years, severe kyphoscoliosis and lack of vascular access presented insurmountable challenges to implement the desired surgical procedure for removal of stones from a solitary kidney.

Adult↗
PubMed1999

Extracorporeal shock wave lithotripsy for lower pole calculi: our experience.

INTRODUCTION: This study was performed in order to evaluate the immediate and long-term outcome of patients undergoing extracorporeal shock wave lithotripsy (ESWL) for isolated lower pole calculi. METHODS: Three hundred and seventy renal units of 350 patients (240 men and 110 women; mean age 55 years) with isolated lower pole renal stones of smaller than 2 cm2 were studied. Follow up ranged from 1 to 52 months (mean, 15 months) to time of censorship, significant period of secondary urologic evaluation. RESULTS: Out of 370 renal units in 350 patients, 212 (57, 29%) were stone-free 1 month after ESWL and 21 (5.67%) spontaneously became stone-free within another 1-52 months (mean, 15 months). Intervention was required after 1-52 months (mean, 17.5 months) and accomplished by ESWL alone (30/350 patients 8.57%) or combined with retrograde endoscopy (10/350 patients 2.85%) while retrograde manipulation was necessary in two of the 350 patients (0.57%). CONCLUSION: Extracorporeal shock wave lithotripsy is the initial treatment of choice in patients with lower pole stones < 2 cm2, because the overall stone-free rate is acceptable and because even in the residual calculi, the risk of suffering symptomatic episodes requiring secondary intervention is low.

Female↗
PubMed1996

Indapamide (Natrilix): the agent of choice in the treatment of recurrent renal calculi associated with idiopathic hypercalciuria.

OBJECTIVE: To compare the hypocalciuric and potential side-effects of hydrochlorothiazide (HCT) to indapamide (IND; a thiazide-like drug) in patients with idiopathic hypercalciuria. PATIENTS, SUBJECTS AND METHODS: Twelve patients with recurrent renal calculi and renal hypercalciuria were studied using a randomized double-blind cross-over protocol. In addition, because the side-effects of HCT are attenuated using small doses, the hypocalciuric effect of 12.5, 25 and 50 mg daily was assessed in six normal subjects. RESULTS: There was a significant reduction in urinary calcium excretion using both agents, with a mean (SD) of 6.06 (2.68) and 3.37 (2.00) mmol/24 h using IND, and 5.58 (1.98) and 3.93 (2.35) mmol/24 h using HCT, before and after treatment (P < 0.05). The treatment was not sufficiently prolonged to assess adequately all the side-effects of either agent but both produced a similar decrease in serum potassium, whilst HCT significantly increased the mean (SD) serum urate levels, from 0.34 (0.09) to 0.43 (0.08) mmol/L (P < 0.01). There was also a significant decrease in mean (SD) urinary citrate excretion in those receiving HCT, from 1.41 (1.05) to 1.00 (0.71) mmol/24 h (P < 0.001), but not in those receiving IND, from 1.19 (0.71) to 1.18 (0.79) mmol/24 h. Although there was a hypocalciuric effect with doses of 12.5 and 25 mg HCT, it was sub-therapeutic when compared with the dose of 50 mg. CONCLUSION: At a daily dose of 2.5 mg, IND is at least as effective as 50 mg HCT in controlling hypercalciuria. Because of its safety profile and lack of effects on urinary citrate excretion, this agent should be the preferred therapy for patients with idiopathic hypercalciuria and recurrent renal calculi.

Calcium↗
PubMed1998

Long-term results of intrarenal surgery for branched calculi: is such surgery still valid?

OBJECTIVE: To evaluate whether intrarenal surgery for branched calculi remains valid in the light of current new techniques, e.g. percutaneous nephrolithotomy and extracorporeal shockwave lithotripsy. PATIENTS AND METHODS: Between January 1978 and October 1984, 44 patients (24 male and 20 female, mean age 42.5 years, range 14-66) underwent complex surgery for large stones, requiring opening of the renal pelvis and a transparenchymal approach to the calices; 47 renal units were operated in 49 procedures. The evaluation before surgery included creatinine and blood nitrogen levels, blood pressure measurement, urine culture, abdominal plain X-ray (44 patients), intravenous urography (42) and isotopic renography with renal scintigraphy (five). Renal lithiasis was categorized and all patients underwent extended pyelolithotomy with a transparenchymal approach, achieved by partial nephrectomy (six patients), radial paravascular nephrotomy (10), posterior lower nephrolithotomy (29), resection of the posterior segment (two), and posterior segmentotomy and reconstruction (2); 16 operations were performed under ischaemia. In October 1996, the patients were clinically evaluated by serum creatinine levels (42), urine cultures (42), abdominal plain X-ray (42), IVU (34), isotopic renography (eight), renal ultrasonography (eight) and blood pressure measurement (44). The mean follow-up was 14.8 years. RESULTS: The major postoperative complications were; residual stones (six patients), fistula with ureteric stenosis (one, with a permanent nephrostomy), toxic temporary hepatic failure (one), femoral arterial embolism (one, resolved using a Fogarty catheter) and recurrent large stones (two, operated 1 and 5 years later). From 1984 to 1996, 19 patients had recurrent stones and two underwent dialysis. In October 1996, the renal function of 47 renal units was stable or normal in 36 (77%), reduced in seven (15%) and lost in four (8%); 24 patients were hypertensive (12 preoperatively), nine have urinary tract infection, three are positive for hepatitis B or C virus, and lithiasis has recurred in 15 renal units. CONCLUSIONS: Intrarenal surgery, conducted using modern anatomical guidelines, was an effective treatment for renal branched stones. The long-term results are satisfactory after appropriate correction of the urinary tract, with the consequent prevention of stasis and chronic infection. The definitive comparison between surgical and combined endoscopic/extracorporeal methods will only become clear when there is a comparable follow-up. Currently, surgery remains preferable in patients with giant calculi, a small pelvis and prevalent calyceal development.

Adolescent↗
PubMed1999

Extracorporeal shock wave lithotripsy of renal calculi during early pregnancy.

OBJECTIVE: To evaluate the safety of renal stone treatment by extracorporeal shock wave lithotripsy (ESWL) during pregnancy. PATIENTS AND METHODS: Data from 824 women of reproductive age who were treated by ESWL were analysed and the patients surveyed using a questionnaire about pregnancies, to which 636 (76%) responded. Of these patients, six had inadvertently undergone ESWL for renal stones during the first month of pregnancy. The stones were detected and located during ESWL using ultrasonography. RESULTS: The six patients gave birth to six children who had no detectable malformations or chromosomal anomalies. CONCLUSION: Although these results suggest that there were no adverse effects of ESWL during early pregnancy, a larger series should be assessed to confirm the safety and long-term effects of ultrasound-guided ESWL in the treatment of renal calculi during pregnancy. We do not advocate lithotripsy as a treatment for renal calculi in pregnancy, but inadvertent lithotripsy in a pregnant woman is not a cause for concern.

Adult↗
PubMed1999

Primary in situ extracorporeal shock wave lithotripsy in the management of ureteric calculi: results with a third-generation lithotripter.

OBJECTIVE: To review the results of primary in situ extracorporeal shock wave lithotripsy (ESWL) for the treatment of ureteric stones using a third-generation lithotripter, the Dornier MFL 5000 (Dornier Medizentechnic, Germany). PATIENTS AND METHODS: The study comprised a retrospective review of treatment outcome in 180 patients with 196 stones who were treated with primary in situ ESWL, assessing the success of this approach and establishing reasons for failure. RESULTS: At the 3-month follow-up, 88% of patients were stone-free; 21 patients failed ESWL and were treated by ureteroscopic stone extraction with no complications. Stone-free rates were 90% for upper ureteric, 89% for middle-third and 86% for lower-third calculi. Twenty-one patients required auxiliary procedures in the form of JJ stenting or nephrostomy. Failure of ESWL was associated with stone size (>1.3 cm) but not location or inadequate treatment. CONCLUSION: Where prompt access to ESWL is available, primary in situ ESWL remains an effective form of treatment for all ureteric calculi, although stone-free rates are lower for larger stones.

Female↗
PubMed2000

Lack of correlation between water hardness and salivary calculi in England.

Our aim was to test the hypothesis that residents of hard water areas are at increased risk of developing salivary calculi. The evidence based on figures from the Hospital Episode Statistics database for the years 1991 to 1994, suggests that there is no such association. For example, in the South West Water area (soft water) the incidence was 28.92/million/year compared with Yorkshire (hard water) 31.64/million/year. The correlation coefficient shows that water hardness is not significantly associated with either the incidence of salivary calculi (r = 0.02, P = 0.9) or that of sialadenitis (n = 2.4, P = 0.4). The lack of association holds for both men and women independently. However, the two conditions have similar patterns of incidence (r = 0.5, P = 0.05), suggesting some common but unknown similarity in aetiology.

Calcium↗