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PubMedDate not supplied

[Urinary calculi in myelomeningocele adults].

INTRODUCTION AND OBJECTIVES: The improvements in the management of newborns with myelomeningocele (MMC) have obtained a big increase in survival, allowing them to get longevity like never before, but data regarding urologic diseases during adult age are still missing. We herein evaluate the features of urinary lithiasis in adults born with MMC and the therapies used for its treatment. MATERIAL AND METHOD: We review 52 patients diagnosed at birth of MMC, between 18 and 40 years old, treated in our institution, with a mean follow-up of 6.7 years. RESULTS: 10 patients (19.2%) were diagnosed of urolithiasis. Three developed kidney calculi and one of them, with 7 more patients, developed bladder calculi (15.3%). The neurological level was < or = L2 in 3 cases, L2-S1 in 5, and > or = S1 in the other two. The type of neurogenic dysfunction of inferior urinary tract was multiple lesion of lower motor neurone in 6 cases, upper motor neurone in 1 case, multiple mixed lesion in 1 case and in case it was impossible to determine. Two patients had a bladder augmentation procedure and one of these with other 3 patients had a non-functional AMS-800 artificial urinary sphincter. Bladder stones were treated endoscopically in 14 procedures and by suprapubic cystolithotomy in 4 procedures, combined with removal of AMS-800 in 3 of them. One patient spontaneously passed a small stone. In one case, 2 ESWL and 2 percutaneous nephrolithotomies were needed. Three patients developed multiple recurrences during follow-up. CONCLUSIONS: Urinary lithiasis is common in adults with MMC. Some distinct features of these patients, together with their anatomical configuration and some therapies used in them, cause diagnostic, therapeutic and prophylaxis issues for the calculi they may develop.

Adolescent↗
PubMed2001

Renal colic and recurrent urinary calculi. Management and prevention.

BACKGROUND: Urinary calculi are a relatively common problem and up to 80% of patients with calculi who are untreated will experience one or more recurrences within five years. OBJECTIVE: This paper outlines the causes of urinary calculi and presents evidence for the less conventional treatment of renal colic with NSAIDs such as intramuscular diclofenac in preference to traditional pethidine injections. The paper also deals with ways to prevent recurrence of stone formation. DISCUSSION: Effective treatment requires a clear understanding of the cause, and investigations need to be directed toward establishing this. Prevention is the cornerstone of management and requires patients to have a clear understanding of the problem. Follow up of these patients is essential.

Australia↗
PubMed1990

Fiberoptic transurethral lithotripsy prefers smaller impacted ureteral calculi rather than large renal stones.

A total of 30 patients with urolithiasis underwent 35 sessions of fiberoptic transurethral lithotripsy (f-TUL) involving electrohydraulic lithotripsy. There were 11 patients with nephrolithiasis including 4 with staghorn calculi and 19 patients with ureterolithiasis which were all located above the pelvic brim. A fiberoptic nephroureteroscope (URF-P) was successfully introduced up to the stone in all but 2 cases (93.3%). Of the 28 patients with successful introduction, 21 received a single session of f-TUL for complete fragmentation of their stones, which measured less than 16 x 9 mm by radiography. Three patients with larger renal stones (greater than or equal to 17 x 9 mm) underwent 2 sessions of f-TUL for complete fragmentation. The remaining 4 patients who had staghorn calculi (greater than or equal to 38 x 33 mm) received 1 session of f-TUL with partial fragmentation; then 3 were sent to an ESWL clinic with good results, while the other patient received 2 more sessions of f-TUL and formed a stone street. Attempts were subsequently made to destroy the latter by ESWL but were unsuccessful. In conclusion, f-TUL appears to be most suitable for smaller impacted ureteral calculi above the pelvic brim.

Adult↗
PubMed1990

[Vesico-prostatic calculi treated by microexplosion lithotripsy: a case report].

A 48-year-old male suffering from neurogenic bladder due to spinal injury was admitted to our clinic with a chief complaint of macrohematuria. Examinations revealed some calculi located in the bladder and in the prostate. Microexplosion lithotripsy for the prostatic calculi (29 x 23 mm etc.) was performed via the urethra and for the vesical calculus (65 x 55 mm) via the suprapubic cystostomy channel. The calculi were fragmented and removed out completely.

Calculi↗
PubMed1989

[Influence of the lithiasic surface on the strategy: complications and results in the treatment of kidney calculi].

Stone mass is a fundamental parameter that determines the approach to reno-ureteral lithiasis. Reference to stone size based on a single diameter gives us an imprecise idea about stone volume. For this reason, we recommend using the term "stone surface" to express stone mass. Stone surface is obtained by multiplying the longitudinal by the transversal diameter expressed in millimeters, using the plain film for radiopaque and the urogram for radiolucent calculi. Stone surface is a parameter which can be determined easily and is a more reliable way to determine stone volume. In 1,500 renal units with reno-ureteral calculi treated by ESWL and percutaneous techniques, we corroborated that the surface of calculus is directly associated with the number of shock waves required for fragmentation. Thus, as stone surface increases, more shock waves will be required to achieve fragmentation. The surface area of the calculus correlates very significatively with urinary tract obstruction post-ESWL. As the surface of the fragmented stone increases, there exists a higher incidence of obstruction. Obstruction is more severe and more ancillary maneuvers to remove obstruction are warranted. The incidence of renal colic post-ESWL is significantly influenced by the surface area of the calculus. There is a higher incidence of reno-ureteral colic following fragmentation of large stones. Furthermore, stone surface significantly determines the rate at which fragments are passed, and the persistence of stone sand at 3 months. Thus, as stone surface increases, there will be more fragments that can and cannot be spontaneously passed following treatment with ESWL. Finally, it must be emphasized that stone surface is a fundamental parameter that determines the combination of ancillary techniques prior to ESWL and significantly influences the efficacy of the approach in the treatment of reno-ureteral calculi.

Biometry↗
PubMed1987

[Ureteral injury in endourological treatment of renal and ureteral calculi].

Percutaneous and transurethral removal of renal and ureteral calculi was performed in 109 cases. Targeted calculi were successfully removed in 105 cases (96.3 per cent), but in five cases combined percutaneous and transurethral procedures were required. Although endourological stone removal resulted in low morbidity rates in many other series, some major complications have also been reported. They include arteriovenous fistula, colo-cutaneous fistula, nephro-duodenal fistula and ureteral avulsion. There were two severe complications in our early experience as well. In one case, a ureteral stenosis was found seven months after two sessions of percutaneous ultrasonic lithotripsy for an upper ureteral stone, and in the other case, a mid-ureteral avulsion was caused by ureteroscopic manipulation. Besides these, we experienced several minor pelvic and ureteral perforations which were easily controlled only by ureteral stent placement. Causes and management of ureteral complications in endourological treatment of renal and ureteral calculi are discussed.

Adolescent↗
PubMed1984

Fluoroscopically guided percutaneous extraction of upper urinary tract calculi.

Recent developments in instrumentation have revolutionized the management of renal and ureteral calculi, so that over 90 per cent of all upper urinary tract calculi can presently be treated by means of percutaneous manipulations. Approximately two thirds of these stones can be extracted under either fluoroscopic or nephroscopic control, with the remainder disintegrated under nephroscopic control with ultrasonic or electrohydraulic energies. The authors describe techniques and equipment for fluoroscopically guided percutaneous extraction of renal and ureteral calculi.

Adult↗
PubMed1998

Haematuria in the diagnosis of urinary calculi.

The aims of this study were to compare the sensitivity of urine dipstix (Combur 9 test) versus urine microscopy in detecting haematuria and to determine the proportion of patients with renal or ureteric colic due to urinary calculi who have haematuria. This is a prospective study of 122 patients presenting to an emergency department in a tertiary teaching hospital with symptoms suggestive of renal or ureteric colic. The same urine specimen tested using dipstix was sent for urine microscopic examination for haematuria, after which a plain radiograph of the kidneys, ureter and bladder was done. An early intravenous urogram was done (delay of an average of 4 days). Telephone interviews were done to determine whether any calculi had been passed. Urine dipstix detected haematuria in 95.4% [95% confidence intervals (CI) 87.1% to 100.0%] of patients with urinary calculi, whilst urine microscopy detected haematuria in 70.8% (95% CI 58.2% to 92.6%). This study showed that urine Combur 9 is more sensitive than urine microscopy in detecting haematuria. The combined use of urine Combur 9 and microscopy does not increase the sensitivity of detecting haematuria. In the absence of haematuria on urine Combur 9 for suspected ureteric colic, alternative diagnoses should be considered.

Adolescent↗
PubMed1975

Biliary and urinary calculi: pathogenesis following small bowel bypass for obesity.

Of 93 patients with small bowel bypass for massive exogenous obesity, three developed calcium oxalate urinary calculi, four stones in their gallbladder, and one developed both gallstones and urinary calculi during a mean follow-up period of 17.6 plus or minus 9.0 months. The urinary oxalate excretion increased from 21.6 to 67.8 mg/24 hours (P smaller than .001); simultaneously, the urinary output decreased from 1,775 to 1,101 ml/24 hours (P smaller than .001). Postoperatively, there was a significant increase in the rate of bile salt synthesis from 1.6 to 4.9 gm/day (P smaller than .02) and in the bile sale glycine/taurine ratio from 4.6 to 6.8 (P smaller than .05). It is suggested that the postbypass increase in the biliary glycine/taurine ratio, with its consequent decrease in the zeta potential of the micelles in bile, is at least partly responsible for the increased incidence of cholelithlasis. The pathogenic basis for the increased incidence of urinary calculi is hyperoxaluria, which is probably related to an increased bile salt and glycine synthesis.

Adult↗
PubMed1999

In vitro study concerning the efficiency of the frequency-doubled double-pulse Neodymium:YAG laser (FREDDY) for lithotripsy of calculi in the urinary tract.

BACKGROUND AND OBJECTIVES: In a preclinical study we have tested both in vitro and in vivo, a new type of pulsed solid-state laser system that has not been applied in urology so far and has been developed for optimized intracorporal lithotripsy of biliary, salivary, and urinary calculi. STUDY DESIGN/MATERIALS AND METHODS: Sixty one calculi from the human urinary tract were split in vitro into fragments with a remaining particle size of </= 2 mm using the prototype of a short-pulsed passively Q-switched and frequency-doubled double-pulse Neodymium:YAG laser. In a supplementary animal test, the bladder mucosa of five rabbits was directly exposed to a highly rated laser beam to be able to assess the tissue lesion potential of the system. RESULTS: All the 61 urinary calculi with different composition were successfully split in vitro within a short period of time (2.5 +/- 4.6 minutes). During histopathologic examination of the exposed bladder walls of the rabbits only a small tissue lesion potential with urothelium changes exclusively at the surface was ascertained. CONCLUSION: The high degree of fragmentation efficiency, the purchase and maintenance costs, which due to its design are substantially lower in comparison to other laser lithotriptors, and the high degree of safety during application make this new laser a real alternative not only to the present laser lithotripsy systems but also to common ballistic lithotriptors.

Animals↗
PubMed1999

Spectroscopic and ultrastructural comparative study of cystine calculi in humans and dogs.

The careful analysis of cystine calculi may be important to detect the presence of other urinary alterations (such as hyperuricosuria, hypercalciuria, hyperoxaluria or bacterial infections) that coexist with cystinuria in many patients. For this reason, in the present study, 14 human and 17 canine cystine uroliths have been studied by infrared spectroscopy (IR), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDX). According to the infrared analysis, most of the human and canine stones were composed of nearly pure cystine. However, in these calculi of apparently pure cystine, the study by SEM and EDX showed in many cases the presence of small amounts of calcium apatite. The infrared study of several samples heated at 750 degrees C confirmed the presence of phosphate, when it was difficult to detect this component in the spectra of the original samples owing to band overlapping. Other components detected in varying proportions in cystine calculi were magnesium ammonium phosphate hexahydrate (struvite), calcium hydrogen phosphate dihydrate (brushite), calcium oxalate (mono and/or dihydrate) and, in one case, a drug (oxolinic acid).

Animals↗
PubMed2005

Modern management of salivary calculi.

BACKGROUND: The aim was to investigate the results of a minimally invasive approach to the management of salivary calculi. METHODS: Four hundred and fifty-five salivary calculi (323 submandibular and 132 parotid) were treated using extracorporeal shock-wave lithotripsy (ECSWL), fluoroscopically guided basket retrieval or intraoral stone removal under general anaesthesia. The techniques were used either alone or in combination. RESULTS: ECSWL achieved complete success (stone and symptom free) in 87 (39.4 percent) of 221 patients (84 of 218 primary and all of three secondary procedures; 43 of 131 submandibular, 44 of 90 parotid). Basket retrieval cured 124 (74.7 percent) of 166 patients (103 of 136 primary and 21 of 30 secondary procedures; 80 of 109 submandibular, 44 of 57 parotid). Intraoral surgical removal was successful in a further 137 (95.8 percent) of 143 patients with submandibular stones (99 of 101 primary, 36 of 38 secondary and two of four tertiary procedures). The overall success rate for the three techniques was 348 (76.5 percent) of 455. CONCLUSION: A minimally invasive approach to the management of salivary calculi is to be encouraged. All three techniques described have low morbidity and afford the possibility of retaining a functional gland.

Adolescent↗
PubMed1992

Microhardness measurements of renal calculi: regional differences and effects of microstructure.

Microhardnesses of five types of renal calculi: calcium apatite (82.5%)/magnesium ammonium phosphate hydrogen (10%)/calcium oxalate monohydrate (7.5%); calcium apatite (95%)/calcium oxalate monohydrate (5%); magnesium ammonium phosphate hydrogen (90%)/calcium apatite (10%); calcium oxalate monohydrate (85%)/calcium apatite (15%); and cystine (100%) were measured. Using Knoop and Vickers indenters the effects of chemical composition and microstructure on the microhardness measurement were assessed. Calcium oxalate monohydrate, magnesium ammonium phosphate hydrogen, and cystine stones, without apparent structure pattern, showed neither regional nor directional differences in their microhardness. In contrast, calcium apatite stones, with distinctly concentric laminae structure, showed regional variations which were correlated with the chemical composition of stone constituents. Scanning electron microscopy of the indenter impressions were taken to help in interpreting the directional dependence in Knoop hardness measurements with respect to the microstructure of the calculi. Vickers measurements showed the crystalline stones were isotropic within a layer. Combined results of Knoop and Vickers measurements indicate that the anisotropic Knoop hardness readings seen in the laminated regions were structural but not material-based. Implications of the results for the fragmentation of renal calculi in extracorporeal shock wave lithotripsy are discussed.

Hardness Tests↗
PubMed1985

Prostatic calculi: a review.

Prostatic calculi are rare in children, infrequent below age 40, and common in males over 50. They may be solitary but usually occur in clusters and are associated with some other disease process (nodular hyperplasia, prostatic carcinoma, metabolic abnormalities). They are most often asymptomatic; however, symptoms that may be attributable to prostatic calculi include reduction of the urinary stream, prostatism, and intense lower back and leg pain. Treatment may be accomplished by transurethral resection, but prostatectomy is the best means to insure complete removal. Prostatic calculi may form by two related mechanisms with obstruction and stasis of prostatic fluid as central entities in both. These mechanisms are calcification of corpora amylacea and simple precipitation of prostatic secretion. They may arise spontaneously, initiating an inflammatory reaction that contributes to their growth, or they may arise as the consequence of another pathologic situation producing acinar obstruction. It appears that infection probably occurs secondary to stone formation.

Adult↗
PubMed2000

Analysis of purines in urinary calculi by high-performance liquid chromatography.

A high-pressure liquid chromatography method has been developed for the analysis in urinary calculi of six purines: uric acid, 2, 8-dihydroxyadenine, xanthine, hypoxanthine, allopurinol, and oxypurinol. Separation was conducted isocratically on a reversed-phase column, using 50 mM phosphate buffer (pH 5.5) / methanol (97/3, v/v) as mobile phase. Limits of detection, depending on compound, ranged from 7 to 28 microg/g stone weight. Hitherto, no reports have appeared on other purines present with uric acid in stones, due to lack of a sensitive and specific analytical method. We have now found that all calculi with more than 4% uric acid also contained 1-methyluric and 7-methyluric acids and trace amounts of hypoxanthine, xanthine, and 2,8-dihydroxyadenine. Accurate identification and quantitation of purines in urinary calculi are important for the diagnosis of rare metabolic diseases leading to urolithiasis (xanthinuria, dihydroxyadeninuria), as well as for prevention of iatrogenic complications during treatment with allopurinol of uric acid urolithiasis. The method may be used for reference purposes in clinical laboratories and for research on the pathogenesis of urolithiasis in disorders of purine metabolism.

Chemistry Techniques, Analytical↗
PubMed1988

Renal calculi-urate as a urokinase inhibitor.

The formation of renal calculi is one of the most widely studied urinary ailments. Spectrophotometric analysis of urinary inhibition on the urokinase/plasmin system revealed a significant difference between subjects with and without renal calculi (P less than 0.001). The percentage urokinase/plasmin inhibition in the two groups was 77.1% for those with, and 47.1% for those without renal calculi. Because of the significant (P less than 0.015) positive correlation (r = 0.762) between the percentage inhibition of urokinase/plasmin and urinary urate concentration, the inhibition of urate on urokinase/plasmin and on plasmin and urokinase was investigated. The urokinase/plasmin system was inhibited up to 94.4% with 0.5 mM urate. Inhibition occurred with both low and high molecular weight urokinases. In order to determine which enzyme of the complex was inhibited, each was investigated independently and a 50% inhibition of urokinase activity was obtained with 4 mM urate. It was found that the urine of stone formers contained a higher concentration of urate than the urine of healthy subjects and that at the same time there was a decrease in urinary urokinase activity in these patients.

Adult↗
PubMed1992

Anatomical bases of percutaneous surgery for calculi in horseshoe kidney.

Horseshoe kidney is a renal fusion which combines three anatomic abnormalities: ectopia, malrotation and vascular changes. These anomalies can be recognised separately to varying degrees in unfused kidneys. Necessary modifications of the standard technique for percutaneous nephrolithotomy (PNL) are directly deducible from analysis of the anatomic data of the imaging of horseshoe kidneys. We report our experience with 5 patients (7 kidneys) who underwent PNL for calculi in horseshoe kidneys. The percutaneous approach was performed under ultrasound and fluoroscopic monitoring. In situ disintegration by ultrasonic lithotripsy and nephrostomy drainage were necessary in all cases. Modifications of the standard PNL procedure are related to the anatomic changes. The lower abdominal position of a horseshoe kidney necessitates upper or middle calyceal puncture, while the malrotation necessitates a more posterior puncture. Monitoring of the puncture needle by fluoroscopy as it is advanced postero-anteriorly is more difficult and the risk of the surgeon's hand entering the radiation path is increased. The renal pelvis is deep and a long endoscope may be required. Aberrant segmental vessels may create potential hazards. The majority of problems in location can be avoided by use of an ultrasonically guided needle. Percutaneous nephrolithotomy is the treatment of choice for calculi in horseshoe kidneys for the following reasons: the high incidence of recurrent lithiasis in horseshoe kidney and the complexity of repeated surgical approaches diminish the acceptable results of open surgery; difficulties in focussing on the calculi and drainage problems militate against the success of extracorporeal shock wave lithotripsy (ESWL); PNL has a good success rate and the least morbidity.

Humans↗
PubMed1993

Xanthine calculi presenting at 1 month of age.

Xanthinuria is a rare cause of nephrolithiasis and is usually due to an inherited abnormality in purine metabolism. A 5-year 6-month-old boy was assessed for a history of recurrent episodes of renal colic. The child first presented with symptoms due to xanthine calculi at 1 month of age, the youngest presentation we were able to identify. Xanthine calculi, although rare, should be considered in the differential diagnosis of nephrolithiasis and ureterovesical junction obstruction in children. Xanthine calculi should also be considered when symptoms suggestive of urinary tract infection are present but the urine culture is negative, and when an orange-brown sediment is noted in the urine or similar coloured stains are found in the nappy.

Humans↗