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PubMed1979

Measurement of total-body 40potassium in patients with urate calculi.

Fifty-eight patients with urate calculi and 31 patients with other (non-urate) calculi were examined for total-body potassium by means of a total-body counter. The patients with urate calculosis were found to differ significantly in their total-body K from patients with other calculi as well as from normal subjects. The results indicate that total-body potassium deficiency is one of the factors causing urate calculosis.

Body Composition↗
PubMed1980

Ultrastructural study of apatites in human urinary calculi.

Using transmission and scanning electron microscopy, we have studied the ultrastructure of a number of urinary calculi, mainly composed of calcium phosphate. Three fundamental kinds of calcium phosphates were detected: nonstoichiometric carbonate apatite, nonhexagonal octacalcium phosphate, and calcium-magnesium whitlockite. The influence that the organic matter, substitutions in the phosphate lattice of CO3 and Mg, and apatitic stoichiometry have on the ultrastructure of the calcium phosphate calculi has been detailed. An originating apatitic unity named U2 is assumed to be the responsible for all the different structures of calcium apatites appearing in renal calculi. On the basis of our observations, a mechanism whereby apatites grow is postulated; magnesium functions as an inhibitor for the growing mechanism.

Apatites↗
PubMed1996

Distal ureteral calculi: ureteroscopy vs. ESWL. A prospective analysis.

Two groups of 50 consecutive patients each, with distal ureteric calculi, were treated by ureteroscopy or in situ ESWL (Dornier HM-4 lithotriptor) in order to establish the effectiveness of ESWL at the distal portion of the ureter. In comparison to ureteroscopy, ESWL for distal ureteral calculi was performed on an outpatient basis, required less time, patients had more rapid convalescence and the procedure was simpler and safer. The overall success rate was 100% for ureteroscopy and 92% for ESWL. Our observations showed that in situ ESWL with the Dornier HM-4 lithotriptor is the method of choice for the treatment of distal ureteral calculi.

Adult↗
PubMed1986

Pancreatic calculi containing brushite: ultrastructure and pathogenesis.

Six pancreatic calculi were analyzed by X-ray powder diffraction and scanning electron microscopy. All were found to contain calcite; however, small amounts of two other morphologically distinct deposits containing only Ca were also detected in some of the stones. It is suggested that these substances may be vaterite and aragonite. In addition, significant deposits of brushite, CaHPO4 X 2H2O, were identified on the outer surfaces of three of the stones. This substance has not been previously reported as a constituent of pancreatic calculi, and its presence is surprising since physico-chemical factors such as phosphate concentration and fluid pH do not favor its deposition. We suggest that precipitation of calcite in the pancreatic duct occurs as the primary event in the formation of pancreatic calculi and that it may continue until the duct is completely occluded. Thereafter, further growth causes injury to the duct wall resulting in the calcite core being exposed to phosphate in the tissue fluid. Deposition of brushite follows.

Calcium Carbonate↗
PubMed1984

Percutaneous chemolysis of renal calculi.

Certain types of pyeloureteral calculi can be treated by chemolytic drug irrigation through a percutaneous nephrostomy catheter. Struvite, apatite, and carbonate stones can be dissolved with an acidic solution (hemiacidrin, Suby solution G). An alkaline agent (Tham-E, acetylcysteine) will dissolve cystine calculi. While most uric acid stones are managed by oral alkalinization with sodium bicarbonate or potassium citrate, there are occasions (cardiac, metabolic conditions) where treatment via percutaneous nephrostomy is preferable. Successful nonoperative management of symptomatic calculi has been obtained in 85% of cases with chemolysis of more than 150 stones.

Acetylcysteine↗
PubMedDate not supplied

The management of ureteric calculi without extracorporeal shock-wave lithotripsy.

BACKGROUND: Extracorporeal shock-wave lithotripsy (ESWL) is a relatively new technological adjunct in the treatment of renal calculi, but availability is limited. AIM: The aim of this study was to assess the outcome of ureteroscopic procedures in a unit without on-site ESWL facility. METHODS: A retrospective study of all cases of ureteric calculi presenting to this hospital during the period 1991 to 1997 was performed. RESULTS: One hundred and thirty five patients with a mean age of 46.8 years were evaluated. Ninety-four (69.5%) had their stone successfully manipulated and/or extracted at ureteroscopy. Using strict criteria, 41 patients (30.5%) had failed ureteroscopies. Fourteen (10.4%) suffered complications related to their ureteroscopy, thirteen had their complications treated conservatively and three (2.3%) needed open procedures. CONCLUSION: Ureteroscopy has a high success rate and low morbidity. We continue to advocate ureteroscopy in the initial management of ureteric calculi.

Humans↗
PubMed2005

Analysis of urinary calculi obtained from a patient with idiopathic hypouricemia using micro area x-ray diffractometry and LC-MS.

Urolithiasis is a common complication in patients with hypouricemia. Using a microarea x-ray diffractometer and nanoflow liquid chromatography-mass spectrometry (LC-MS) following SDS-polyacrylamide gel electrophoresis (PAGE), recurrent urinary calculi complicating a hypouricemic patient were analyzed. Analysis with the microarea x-ray diffractometer showed that one of the calculi was composed of calcium oxalate monohydrate and hydroxyapatite. The other was found to be formed from calcium oxalate dihydrate. After determination with LC-MS, both were found to contain uromodulin, albumin, osteopontin, protein Z, and defensins. Lysozyme and calgranulin A were also identified in these calculi. Defensins, which were antimicrobial peptides, and lysozyme, a mucopeptide glycohydrolase, were identified as new organic components of urinary stones. The role of these proteins in the process of urolithiasis is of particular interest.

Amino Acid Sequence↗
PubMed2001

CT urograms in pediatric patients with ureteral calculi: do adult criteria work?

BACKGROUND: Secondary signs of urinary obstruction associated with ureteral calculi are useful adjuncts to diagnosis in adults with renal colic evaluated by unenhanced helical CT. OBJECTIVE: Our purpose was to evaluate the frequency of secondary signs of obstruction in children with renal colic undergoing unenhanced helical CT. MATERIALS AND METHODS: Ureteral calculi were identified in 20 of 61 children with acute flank pain examined by unenhanced helical CT. Each imaging study was evaluated for the presence of secondary signs of urinary obstruction. The frequencies of individual signs were compared with each other by means of the McNemar test. RESULTS: Six children had no secondary sign identified. In the remaining 14 children, proximal ureteral dilatation was seen in 10, renal enlargement in 10, hydronephrosis in 9, tissue rim sign in 6, decreased kidney attenuation in 5, and perinephric stranding in 1. Comparison of the frequencies strongly suggested that perinephric stranding occurs less frequently than proximal ureteral dilatation (P = 0.004), hydronephrosis (P = 0.008), or renal enlargement (P = 0.012). CONCLUSION: Perinephric stranding, a common secondary sign in adults with ureteral calculi, occurs less frequently in children than other reported secondary signs.

Adolescent↗
PubMed2002

Percutaneous imaging-guided access for the treatment of calculi in continent urinary reservoirs.

PURPOSE: To describe our long-term experience with percutaneous access to continent urinary reservoirs for calculus removal. PATIENTS AND METHODS: A retrospective study of 13 procedures in 10 patients was performed. In 2 of the 13 procedures, access and calculus removal was performed in a single session. In the other 11 procedures, initial access was obtained using ultrasonography, fluoroscopy, and/or computed tomography. The patients then returned at a later date for a second step where the access was dilated and the calculi were removed. RESULTS: Access was achieved successfully in all cases with no complications. At mean follow-up time of 13.6 months (range 1-94 months) one patient had died of complications unrelated to her continent urinary reservoir. Another patient had been placed on suppressive antibiotics for recurrent calculi. The remaining patients were stone free and without late complication. CONCLUSIONS: Percutaneous removal of reservoir calculi can be performed safely, avoiding potential injury to the continence valve mechanism by a direct cystoscopic approach. We propose a two-stage procedure using CT guidance for initial access as the preferred technique.

Adolescent↗
PubMed2004

Bilateral urinary calculi after treatment with a silicate-containing milk thickener.

UNLABELLED: Nephrocalcinosis and/or urinary calculi are rare in infants. Furosemide treatment during the neonatal period, vitamin D intoxication, hereditary diseases such as hyperoxaluria or distal tubular acidosis are among the most common aetiologies. We report the case of a 6-month-old boy with an extra-hepatic biliary duct atresia treated by the Kasai procedure and a gastro-oesophageal reflux treated with a silicate containing milk thickener (Gelopectose, 5.5% colloidal silicate) since the neonatal period. He did not present any other endogenous risk factor for urinary stone formation (normal urinary calcium/creatinine ratio; normal urinary magnesium excretion). The nephrolithiasis was discovered as the boy presented painful episodes of macroscopic haematuria. Ultrasound examination revealed bilateral nephrocalcinosis and multiple bilateral calculi without infection or urinary obstruction. Infrared spectroscopy revealed silicate as the major component suggesting silicate absorption to be responsible for the described symptoms. After replacement of the silicate-containing agent by a silicate-free milk thickener, the lesions were completely reversible as confirmed by repeated renal ultrasound examinations over a 2-month period. CONCLUSION: Silicate-containing milk thickeners can be responsible for urinary calculi and/or nephrocalcinosis.

Gastroesophageal Reflux↗
PubMed2005

Percutaneous endoscopic treatment for calyceal diverticular calculi.

A 29-year-old man complaining of gross hematuria was referred to our department. DIP demonstrated calyceal diverticular calculi of the left kidney. The patient requested ESWL, but the stone had not been discharged after two treatments. He then underwent PNL with dilation of the narrow neck of the calyceal diverticulum under fluoroscope. The neck of the diverticulum was dilated using an amplats dilator. Three months after the surgery, DIP demonstrated that the diverticulum was completely free from calculi and the size of the diverticulum was reduced. He was doing well 24 months after the operation. Calyceal diverticular calculi should be managed not only with ESWL and PNL but also with dilation of the narrow neck of the calyceal diverticulum.

Adult↗
PubMed2005

Idiopathic prostatic giant calculi in a young male patient.

We report a case of 41-year-old man with idiopathic prostatic giant calculi presenting with voiding difficulty. To our knowledge this is the youngest case with idiopathic prostatic giant calculi reported in the literature. The etiopathogenesis of prostatic calculi are also discussed.

Adult↗
PubMed2006

Simple radiological indicators for staghorn calculi response to ESWL.

OBJECTIVE: To evaluate staghorn calculi response to ESWL using simple radiological indicators which are stone size, stone homogeneity, and stone density. PATIENTS AND METHODS: This is a prospective study of 60 patients with staghorn calculi where the majority had ESWL. The relationship between response and size, homogeneity and density is studied. RESULTS: Single staghorn calculus less than 4 cm, heterogeneous with stone density similar to bone or a little denser than bone has best response to ESWL. CONCLUSION: ESWL is useful as first line therapy for staghorn calculi less than 4 cm, heterogeneous with similar density to bone or a little denser than bone.

Adolescent↗
PubMed1980

Comparison of infrared and wet chemical analysis of urinary tract calculi.

Infrared analysis of urinary tract calculi using the system of interpretation of spectra of Oliver and Sweet [1] was compared with qualitative wet chemical analysis. This method of interpretation could be learned quickly and gave reproducible results, but had some limitations. Advantages of the infrared procedure include greater reproducibility. 1-mg sample size, greater sensitivity for oxalate and more uniform sensitivities. Minimum detectable amounts of reference standards varied roughly within 1 order of magnitude, compared with a range of 10(5) for wet chemical procedures. The comparable sensitivity for oxalate and phosphate permits a semi-quantitative approach for infrared. The main problems relate to the detection of magnesium ammonium phosphate and carbonate apatite, and wet chemical tests are recommended in addition, when these compounds are suggested. Calculi from 308 patients were analyzed by infrared. With this system of interpretation of spectra, infrared is considered to be a major advance in methodology for analysis of urinary tract calculi in the clinical laboratory, compared with qualitative wet chemical procedures.

Calcium↗
PubMed1988

Identification of renal calculi by computerized infrared spectroscopy.

A method is described for the assessment of renal calculi by means of a computerized IR spectrometer. A preliminary reference library of IR spectra of 34 different renal calculi of known composition has been created. The reference library used in the operation of a computerized search program indicates the closest matches in the reference library data with the IR spectrum of an unknown sample. The computerized method of characterizing renal calculi has the advantage that it greatly reduces the likelihood of introducing errors because of operator bias in the subjective interpretation of spectral data.

Electronic Data Processing↗
PubMed1984

Salivary calculi and chronic sialoadenitis of the submandibular gland: a radiographic and histologic study.

This study correlated radiographic observations and histologic findings of submandibular glands with the diagnosis of salivary calculus and/or chronic sialoadenitis. During a 15-year period eighty-eight patients satisfied clinical requirements by having a radiographic examination performed prior to gland extirpation. Salivary calculi were present in 83% of the patients. The diagnostic accuracy of radiographs regarding salivary calculi in the submandibular gland system was 92%. Radiolucent calculi constituted 20% of the total number of cases with concrements. Failure to disclose concrements was caused by lack of contrast filling due to a damaged gland which presumably camouflaged radiolucent concretions. Ductal changes observed in sialograms corresponded to histologic changes in the glandular parenchyma in 96% of the cases. The absence of ductal change in sialograms did not necessarily indicate a nondiseased gland.

Adolescent↗
PubMed1980

Use of cryoprecipitate coagulum in extracting renal calculi.

Human cryoprecipitated plasma can form an extractable coagulum which will effectively remove renal calculi in selected cases. We successfully used this blood product and a simplified injection technique in 30 patients undergoing surgery for upper tract calculi. Coagulum pyelolithotomy was performed in 24 cases with removal of all stones in 23 (96 per cent). In 6 patients incomplete stone removal by conventional operative methods was successfully completed by using the coagulum as an adjunctive procedure. In 10 of the 30 cases (33 per cent) radiographically "silent" calculi were recovered within the cryoprecipitate clot. The advantages of cryoprecipitate over previously reported blood products, certain technical simplifications, and the appropriate clinical indications for the coagulum procedure are discussed.

Adult↗
PubMed1981

Giant vesical calculi in the female.

We herein report a case of giant vesical calculi in the female bladder. To the best of our knowledge, these calculi represent the largest group of vesical calculi ever removed from the female bladder. The etiologic factors that contribute to bladder calculus formation in the female are discussed.

Aged↗