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PubMed2003

[Study on the epidemiology and risk factors of renal calculi in special economic zone of Shenzhen city].

OBJECTIVE: To study the epidemiological characters and risk factors of renal calculi in Shenzhen for future intervention. METHODS: Risk factors of renal calculi were analyzed by factor analysis and linear structural relation model, followed by fitting and evaluating the model. RESULTS: The prevalence rates of renal calculi were 8.00% and 5.12% in males and females. The results of LISEREL showed that the total effect of age and sex affecting the development of renal calculi was 0.4614, with directly effect 0.3600 and indirect 0.1014. The direct effects of blood uric acid, blood calcium and body mass index, blood cholesterol, blood sugar were 0.3400 and 0.3200 respectively. The indirect effect of education, exercise and dietary habit affected the development of renal calculi through index of biochemistry and obesity, were -0.0416 and 0.1882. CONCLUSION: Sex, age, obesity and high blood cholesterol, high blood sugar, high blood uric acid, high blood calcium were the direct influencing factors to renal calculi. At the same time, education, exercise and dietary habit were also associated with the disease.

Age Factors↗
PubMed1992

[Cystine calculi: x-ray diffraction study. Infrared spectroscopy and SEM].

The present study investigated cystinuria and cystine calculi. Inexplicably, of 987 calculi that had been analyzed ultrastructurally at the Department of Urology of the University Hospital of Salamanca over a period of 15 years only 3 (0.3%) were cystine. The foregoing finding does not coincide with the 0.5-1% incidence reported in the world literature. Apart from the chemical analyses, infrared spectroscopy disclosed the typical findings of multiple bands 1600-625 cm-1. Analysis by x-ray diffraction revealed a slight variation from the ASTM values. One of the calculi, which we considered to be a mixed calculus (probably of calcium phosphate), showed a peak at 43 degrees, instead of the usual 34.5. Scanning electron microscopy disclosed two forms of crystallization: The typical hexagonal form of cystine stones and the rectangular form of different sizes. The material comprising the matrix was observed in many areas, covering and joining the crystals as if it were cement. Whenever possible, treatment of these recurrent calculi should be conservative. Some advocate the use of ESWL, although others consider these calculi to be extremely hard and, therefore, not amenable to ESWL. Chemical dissolution is advocated by some, although its critics consider it to be of little use. Concerning prophylaxis, forced fluids and alkalinization may reduce recurrence. Ultrastructural studies have provided further insight into the structure and composition of cystine calculi. The foregoing may be useful in determining the most appropriate form of treatment based upon stone size, shape, composition (pure or mixed), etc.

Adult↗
PubMed1991

[Long ureteral ammonium-magnesium phosphate (struvite) and calcium phospho-carbonate calculi].

The authors report about 12 cases of long ureteral calculi, 16 to 39 mm in size, observed over 10 years. They were all made of a mixture of ammonium-magnesium phosphate and calcium phosphocarbonate. Infection was the revealing symptom, either in the form of simple bacteriuria or as acute pyelonephritis or sepsis. These calculi, found in a lumbar or pelvic location, were very long, radiopaque but with a moderate radiological density, homogeneous and have regular contours. They were straight, sometimes slightly bent, rarely (one case out of 12) arciform. In 11 of 12 cases, the affected patient was female. In most cases, the urine was infected by Proteus mirabilis. In spite of their size, the calculi caused total obstruction in 3 of 12 cases only. They were or were not associated to ipsilateral coral calculi of the same chemical type. Destruction was easily achieved with physical agents. The etiological, radiological and therapeutic characteristics of these calculi give them a specific place among ammonium-magnesium phosphate calculi.

Adult↗
PubMed1990

[Extracorporeal lithotripsy of urinary calculi. Results and radiologic criteria of effectiveness. Apropos of 700 cases].

The results of extracorporeal shock wave lithotrity (Dornier lithotriptor) for 700 cases of urinary calculi have been reviewed and correlated with the radiological features of the calculi in order to define some predictive radiological criteria of effectiveness. The calculi were broken up in 74.5% of all cases, complete destruction (no residual fragment) was achieved in 34.5% and partial destruction in 40% of cases. The rate of failure (failure to break up or scatter the calculus) is 8.9%. Complications were observed in 2.6% of all cases, a second session of lithotrity or a surgical operation was required in 4.8% of cases (evolution lost to follow-up: 9.2%). The comparison of these results with the radiological data obtained before lithotrity allows distinguishing 2 categories of calculi: 1) Calculi with a favorable prognosis: single, smaller than 1 cm, pyelic, not very opaque and heterogeneous, located in normal-sized cavities; 2) calculi with a poor prognosis: multiple, larger than 2 cm, lower calyceal or ureteral, very opaque and homogeneous, located within dilated cavities.

Adolescent↗
PubMed1986

Urinary calculi and urinary tract infection. A clinical and microbiological study.

The problem of urinary calculi in association with urinary tract infection (UTI) was investigated. Fifty-two (7%) of 796 patients attending our outpatient stone clinic had UTI which was considered of pathogenic importance for their stone formation. Proteus was the most common microorganism. Metabolic disorders were found in one third and anatomical and functional abnormalities in two thirds of the patients. The infected patients had lower urinary calcium excretion and higher serum creatinine than idiopathic stone formers and had a higher frequency of stone operations. The prevalence of staghorn calculi as a cause of urimia was low (1.5% of 481 dialysis patients). Eight such patients were studied and six of them had metabolic and anatomical disorders. The time taken for the uremia to develop was 7.4 +/- 2.0 (SD) years. In 535 patients treated surgically for renal calculi, about one third had positive urine culture at the time of operation and E. coli was the most common bacterial strain (35%). Proteus was found in 28% and these patients had the highest frequency of UTI episodes, most of which occurred before hospitalization. Patients infected with E. coli had a higher frequency of phosphate-containing calculi than non-infected patients, in whom the highest frequency of calcium oxalate calculi was found. A new broad-spectrum cephalosporin, ceftazidime, was used as perioperative prophylaxis in 15 patients operated upon for renal calculi and UTI. Ten had bacterial growth in the renal pelvis and all strains were eradicated. Bacterial growth was found in two out of six cultured stones from patients with bacterial growth in the pelvis. The pharmacokinetics of the drug was studied and the decreases in the ceftazidime levels in serum and renal tissue seemed to be parallel. Bacterial binding of urinary isolates to hydroxyapatite (HAP) particles was studied. Two E. coli strains (A5089 and E7704) and one Proteus mirabilis strain (A5076), all obtained from stone patients, were compared with two E. coli strains (2683 and M7810) with well defined cell-surface properties. Hemagglutination tests were performed and the cell-surface hydrophobicity was determined by a salt-aggregating test. When the strains were cultured at 37 degrees C to promote fimbriae formation they hemagglutinated erythrocytes and displayed hydrophobic cell-surface properties, and showed higher capacity for binding to HAP than when cultured at 18 degrees C to suppress fimbriae formation, when they showed almost complete absence of hemagglutination and low cell-surface hydrophobicity. Bacterial cell-surface properties seem to influence the binding of uropathogens to HAP particles.

Acute Kidney Injury↗
PubMed1986

Instrumental neutron-activation analysis of canine urinary calculi for some selected elements.

Thirty canine urinary calculi, most of which had been qualitatively classified as struvite calculi, were analyzed by instrumental neutron activation analysis at the University of Missouri Research Reactor. Measurements of sodium, magnesium, aluminum, silicon, phosphorus, chloride, potassium, and calcium were possible, using a dual irradiation procedure. Magnesium was used to calculate the percentage of struvite mineral, Mg(NH4) (PO4) X 6H2O, in the calculi by making use of the stoichiometric relationship of the element magnesium to the mineral. For those calculi containing greater than 80% struvite, the mean elemental concentrations were found to be 0.12% Na, 9.35% Mg, 0.0033% Al, 12.1% P, 0.02% Cl, 0.85% K, and 2.05% Ca. A new method for determination of silicon in urinary calculi also was discussed. Two calculi were found to contain 45.0% and 37.3% silicon, and 1 mixed calculus was composed of 1.4% silicon.

Animals↗
PubMed1985

Glucosuria associated with renal calculi in Asian small-clawed otters.

Urine from one female and 2 male Asian small-clawed otters (Aonyx cinerea) with bilateral renal calculi, one female with unilateral calculi, and one nonaffected male were evaluated for abnormal urinary crystalloid excretion. One otter with bilateral renal calculi had cystic calculi composed of calcium oxalate monohydrate and dihydrate. The 2 affected males were littermates, as were the 2 affected females, but the 2 litters were from different parents. At the time of the study, the otters did not have clinical signs of disease. Hematologic and serum biochemical, electrolyte, and enzyme values were normal. The urinary excretion of calcium, oxalate, uric acid, phosphate, citrate, and amino acids in otters with renal calculi was similar to that of the nonaffected otter. The 4 otters with renal calculi had glucosuria but the nonaffected otter did not have glucosuria. The glucosuria, in the absence of hyperglycemia, suggested a renal tubular transport defect for glucose. Other renal abnormalities were not found.

Animals↗
PubMed1985

Ultrastructure and chemical composition of calcite urinary calculi in Chinese swamp buffalo.

Four urinary calculi, derived from Chinese swamp buffalo, were studied by using qualitative chemical analysis, X-ray diffraction, scanning electron microscopy and qualitative energy dispersive (electron probe) microanalysis. Qualitative chemical analysis showed that the predominant ions were calcium and carbonate with small amounts of magnesium and ammonium. X-ray diffraction confirmed that the calculi were primarily composed of calcium carbonate (calcite). On ultrastructural examination, three apparently distinct structural regions were identified in the calculi: outer large laminations; cavities containing variable numbers of small spheres and rods; and large spheres. There did not appear to be material that acted as a nidus and all regions, on qualitative electron probe analysis, contained primarily calcium with trace amounts of magnesium, phosphorus, potassium and chloride. It was concluded that calcite calculi in Chinese swamp buffalo are probably formed through a process of asynchronous layering and that nidus formation may not be necessary. Moreover, the ultrastructure of the calcite calculi is similar to that reported for siliceous calculi in ruminants and this suggests that similar factors may be involved in their formation.

Animals↗
PubMed1983

Urinary tract calculi in children.

One hundred and nine children with urinary tract calculi were reviewed and in some cases reinvestigated. Eighteen children had lower urinary tract calculi, which in all cases were associated with an underlying urodynamic abnormality. Sixty percent of 91 children with upper urinary tract calculi could be classified into 4 similarly sized etiological groups: an underlying urodynamic abnormality; urinary tract infection without a urodynamic abnormality; metabolic disorders; idiopathic hypercalciuria. An underlying abnormality was not found in 32% of cases. A painless presentation occurred in 39% of those with upper tract calculi. A family history of urinary calculi occurred in approximately one-half of children with either an idiopathic calculus or a calculus associated with cystinuria or idiopathic hypercalciuria. We conclude that urinary tract calculi, though rare in children, require extensive investigation to rule out urodynamic, infective and metabolic abnormalities. If such abnormalities are not found, the recurrence rate in the remainder is small and conservative treatment can usually be recommended.

Adolescent↗
PubMed1981

Mineral composition of urinary calculi from miniature schnauzer dogs.

The mineral composition of 150 calculi from the urinary tracts of Miniature Schnauzer dogs was determined by qualitative and quantitative methods. Struvite was the predominant mineral in 92% of the calculi. Other calculi contained predominantly apatite, calcium oxalate, ammonium urate, or silica. Most calculi were from the urinary bladder or urethra, or both. Four were from the renal pelves. Struvite calculi were more frequently encountered in females than males. The mean age of the dogs at the time of detection of calculi was 4.8 years. Qualitative analysis failed to detect some minerals that were identified by quantitative analysis.

Animals↗
PubMed1995

[Pneumatic intracorporeal lithotripsy of salivary calculi. In vitro and animal experiment studies].

BACKGROUND: The effort to use minimally invasive strategies in the treatment of human sialolithiasis in principle seems to allow the clinical application of pneumatic lithotripsy because of the small diameters of the probes involved. While this kind of therapy is already used successfully in urology, we investigated the method during in vitro and animal experiments. MATERIALS AND METHODS: The treatment of stones and tissue utilized the pneumatic lithotripter "Lithoclast". This system works with ballistic energy and is similar to a biologic "pneumatic hammer". Thirty salivary calculi were treated with pneumatic lithotripsy. Four submandibular salivary glands and their ducts were removed intraoperatively and were exposed to the pneumatic probes. Moreover, in two cases a salivary concretion was also implanted prior to pneumatic lithotripsy. In two rabbits the ducts of the parotid glands were ligated for 2 weeks. On the basis of the in vitro experiments, concretions were placed in two of the four salivary ducts. Following this, the pneumatic probes were inserted along the ducts and lithotripsy was completed. RESULTS: All of the 30 salivary calculi were reduced to sizes smaller than 1.5 mm in diameter. No macroscopic or microscopic damage was detectable while the probe was in a duct. However, in both cases with implanted calculi retropulsion of fragments occurred consequent perforation of the ducts. After application of ballistic pulses along the duct, small periductal hematoma without any perforation were detected macroscopically. Microscopically, only small bleeding was observed along the submucosa and partial loss of epithelium was found. In contrast, the pulse application to the implanted concretions lead to destruction of the calculi with perforation of the ducts as well as hemorrhage in the surrounding tissue. CONCLUSIONS: The method of pneumatic lithotripsy used in the present study resulted in sufficient destruction of salivary calculi. In vitro and in vivo lithotripsy of duct implanted calculi led to perforation of the salivary duct in all cases. Because of these results, the clinical use of this technique to treat human sialolithiasis appears to be not justified.

Animals↗
PubMed1994

Ultrastructure and mineral composition of urinary calculi from horses.

Urinary calculi from 17 horses with urolithiasis were examined to study their mineral content and ultrastructure. Among the analytic methods used were X-ray diffractometry, scanning electron microscopy, and electron microprobe analysis. The calculi initially were observed by use of a stereoscopic dissecting microscope and generally were found to have nodular surfaces surrounding a banded or granular-to-chalky interior. Observation by scanning electron microscopy revealed an intricate pattern of irregularly concentric, fine bands and spherules. These had a round, finely banded, globular texture formed by precipitation of ultrafine-grained radiating crystals. The original pore spaces (ie, between spherules, between bands and spherules, or between crystal generations) could be observed as primary porosity. Precipitation and dissolution of these urinary calculi were observed to be spontaneous processes, which can occur simultaneously within an individual calculus. Another prominent feature of the ultrastructure was secondary porosity (spontaneous dissolution) which, in its incipient stages, appeared to be site-selective (ie, some bands appeared to be more susceptible to development of pinpoint porosity). Textures indicative of dissolution were observed not only on the calculus surface, but within the calculus interior as well. Areas that had more advanced stages of dissolution, resulting in increased secondary porosity, also were observed. All 17 samples of the study were found to be composed of calcium carbonate in the form of the mineral calcite, although minor quantities of 2 other polymorphs of calcium carbonate, minerals vaterite and aragonite, also were encountered. Vaterite was observed in 5 of the samples, whereas aragonite was found in 1 sample. Strontium and sulfur were observed as trace elements in 3 of the calculi, whereas magnesium was present in all calculi. Magnesium was observed to substitute for calcium within the calcite crystal lattice in larger quantities than those of strontium or sulfur. Magnesium K alpha X-ray dot maps generated by use of an electron microprobe analyzer indicated that the distribution pattern of magnesium appeared to closely follow layer-by-layer growth of the calculus. Magnesium distribution also appeared to be related to porosity development. In samples where preferential dissolution was observed, the more porous areas had higher magnesium content. Quantitative chemical analyses, using the electron microprobe analyzer, confirmed these observations. Association of the magnesium distribution pattern to the primary growth texture of the calculus indicated that magnesium content of the calculus varied during the formation process. This also indicated that changes in urine chemical analytes may be reflected in composition of the calculi formed.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1993

[Treatment of staghorn calculi by extracorporeal shock wave lithotripsy monotherapy].

We evaluated retrospectively 107 patients with staghorn calculi who underwent extracorporeal shock wave lithotripsy (ESWL) monotherapy from 1985 to 1990. The 107 patients consisted of 65 complete staghorn calculi and 55 partial staghorn calculi. Staghorn calculi required an average of 4.3 treatment sessions. Using a Dornier HM3 lithotriptor, the stone-free rate was 33% in patients with complete staghorn calculi, and 35% in patients with partial calculi. For stone evacuation following ESWL procedure, ureteral stenting, nephrostomy and transurethral lithotripsy were necessary. Four of the 21 patients who underwent ESWL monotherapy and were available for long-term followup showed stone growth, while all of the 10 patients who underwent open surgery during the previous 5 years became stone free. The average period of hospitalization and cost were 38.3 days and 700,000 yen in patients who had received open surgery, and 25.8 and 1,720,000 yen in patients receiving ESWL monotherapy. In conclusion, ESWL monotherapy is useful, and if patients require complete removal of all stone fragments, a percutaneous lithotripsy should be performed following ESWL monotherapy.

Adult↗
PubMed1993

[Clinical application of a third generation lithotripter (Therasonic) for upper urinary tract calculi].

A third generation lithotripter (THERASONIC Lithotripsy Treatment System) was used for disintegration of upper urinary tract calculi. A total of 115 patients was treated at Miki Municipal Hospital, 54 with renal calculi, 8 with UPJ calculi, 30 with upper and 23 with lower ureter calculi. The stone-free rate one month after treatment was 89%, 88%, 90% and 100% for renal, UPJ, upper ureter and lower ureter calculi, respectively. As for side effects, we experienced two cases of perinephric hematoma which were treated conservatively. However, we encountered no other severe complications. These findings clearly indicated that the THERASONIC lithotripter is highly useful for disintegration of calculi of the upper urinary tract.

Adolescent↗
PubMed1995

[A case of soft renal calculi with xanthogranulomatous change].

A case of soft renal calculi with xanthogranulomatous change is reported. A 37-year-old female visited our hospital on February 4, 1992 complaining of frequency of urination and right lower abdominal pain. Under the clinical diagnosis of right renal calculi, extracorporeal shock wave lithotripsy was attempted, but no sign of destruction was observed. Right pyelolithotomy was performed on June 8, 1992. Several soft calculi were removed from the right renal pelvis. Microscopic examination showed that the calculi were surrounded by a cell layer including foam cells and giant cells. In addition, the calculi revealed positive reaction by several stainings (alcian-blue, PAS and muticarmin), which showed that the calculi were mainly composed of mucopolysaccharides. We discussed this disease in terms of symptoms, diagnosis, treatment and mechanism in comparison with previous reports.

Adult↗
PubMed1996

Ultrastructure of selected struvite-containing urinary calculi from cats.

OBJECTIVE: To elucidate the ultrastructural details of struvite-containing urinary calculi from cats. DESIGN: Specimens studied were inclusive of the range of textures visible during preliminary analysis by use of a stereoscopic dissecting microscope. Textural types, which were used to infer crystal growth conditions, were differentiated with regard to crystal habit, crystal size, growth orientation, and primary porosity. SAMPLE POPULATION: Thirty specimens were selected from a collection of approximately 1,600 feline urinary calculi: 20 of these were composed entirely of struvite, and 10 consisted of struvite and calcium phosphate (apatite). PROCEDURE: Qualitative and quantitative analyses of specimens included use of plain and polarized light microscopy, x-ray diffractometry, scanning electron microscopy with backscattered electron imagery, x-ray fluorescence scans, and electron probe microanalysis. RESULTS: Four textural types were recognized among struvite calculi, whereas 2 textural types of struvite-apatite calculi were described. CONCLUSIONS: The presence of minute, well interconnected primary pores in struvite-containing urinary calculi from cats is an important feature, which may promote possible interaction of calculi with changes in urine composition. CLINICAL RELEVANCE: Primary porosity, which can facilitate interaction between the calculus and changing urine composition, may explain the efficacy of dietary or medicinal manipulations to promote the dissolution of struvite-containing uroliths from this species.

Animals↗
PubMed1996

Treatment of ureteral calculi with an 8.3-Fr. disposable shaft rigid ureteroscope.

One hundred forty-two adult patients underwent ureteroscopy for treatment of ureteral calculi using a disposable shaft semirigid mini-ureteroscope. The ureteroscope has an 8.3-French (Fr.) outer diameter with a fiberoptic core that allows some flexibility of the shaft. It has a 4.0-Fr. working channel that allows simultaneous use of 3-Fr. instruments and irrigation. Twenty-nine patients had upper ureteral calculi and 113 patients had lower ureteral calculi. Forty-eight patients did not require ureteral dilation, and the remainder had minimal dilation to 10-12 Fr. One hundred fifteen patients underwent laser lithotripsy, 15 patients underwent basket extraction, and 12 patients underwent both. Ten patients required use of a flexible ureteroscope. Ninety-three percent of the patients went home the day of the procedure, 4% stayed one night in the hospital, and the remaining three percent had longer hospital stays. No major complications or infections were noted. Only 11% of the patients required intravenous or intramuscular narcotics for pain management postoperatively. The stone-free results at one month were 98% for lower ureteral calculi and 93% for upper ureteral calculi. We have found this ureteroscope to be similar to other rigid mini-ureteroscopes with some additional advantages. A larger working channel, increased flexibility, and improved optics make it useful for treating ureteral calculi in the lower ureter in men and the entire ureter in selected women.

Disposable Equipment↗
PubMed1998

Holmium:YAG lithotripsy of uric acid calculi.

PURPOSE: Holmium:YAG lithotripsy of uric acid calculi produces cyanide. We review our experience with holmium:YAG lithotripsy of uric acid calculi to determine if there is any clinical evidence of cyanide toxicity. MATERIALS AND METHODS: A retrospective analysis of all of our cases of holmium:YAG lithotripsy of uric acid calculi was done. Anesthetic and postoperative data were reviewed. RESULTS: A total of 18 patients with uric acid calculi were treated with holmium:YAG lithotripsy by ureteroscopy (5), retrograde nephroscopy (2), percutaneous nephrolithotomy (5) or cystolithotripsy (6). No patient had increased end-tidal carbon dioxide, changes in electrocardiogram or significant decrease in postoperative serum bicarbonate. An 84-year-old woman had decreased diastolic pressure of 30 mm. Hg while under general anesthesia. No cyanide related neurological, cardiac or respiratory complications were noted. CONCLUSIONS: There were no obvious cyanide related complications from holmium:YAG lithotripsy of uric acid calculi. These data suggest no significant cyanide toxicity from holmium:YAG lithotripsy of uric acid calculi in typical clinical settings. Animal studies are warranted to characterize the risk.

Adolescent↗