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PubMed1984

Comparison of recurrence rates of calculi of the bladder in patients with indwelling catheters following vesicolithotomy, litholapaxy and electrohydraulic lithotripsy.

This retrospective review is the first to compare recurrence rates of calculi of the bladder following each of the three common methods. In 39 patients with bladder calculi and indwelling catheters, the recurrence rate of calculi of the bladder within two years was significantly greater following litholapaxy (44.1 per cent) or EHL (50.0 per cent) than vesicolithotomy (7.4 per cent). The average stone-free interval was shorter after litholapaxy (18.4 months) or EHL (13.8 months) than vesicolithotomy (70.8 months).

Adolescent↗
PubMed1984

[Whewellite and weddellite: toward a different etiopathogenesis. The significance of morphological typing of calculi].

From 3000 urinary calculi analysis, a morphological classification allowed us to appoint 7 structural types of oxalate stones, dependent on whewellite or/and weddellite. We observed evidence for correlations between biological data and these structural types, mainly between types I and hyperoxaluria, types II and hypercalciuria, types II + IV or IV and hyperparathyroïdism, as well as between whewellite and hyperuricuria. We determined in vitro calcium and oxalate concentrations ranges to crystallize various hydrate forms of calcium oxalate and we observed that whewellite form is almost the only one fitted for crystallizing in renal papilla. From this various data, it results that, in vivo, whewellite is dependent on oxalate concentration whereas weddellite is rather dependent on calcium concentration. Otherwise, differences in occurrence of morphological types of oxalate calculi were observed as a function of the patient' sex, the urinary tract localisation of calculi, or the crystalluria.

Calcium↗
PubMed1983

Routine analysis of urinary calculi by scanning electron microscopy.

Analysis of 529 urinary calculi by SEM(EDXA) and following x-ray diffraction in nearly all cases of oxalate-rich stones reveals a certain content of calcium phosphate, which in more than 75% can be related to the central core. This confirms the idea of a primary nidus at the beginning of stone formation. The abundant appearance of Ca-phosphate bearing microspherules both in urinary calculi and in urine of known stone formers as well as the presence of similar spherules in human kidney tissue leads to a conception of the physico-chemical nature of this nidus. A proposed model about the first steps of stone formation combines the two main theories of genesis of urinary calculi, which so far have been considered contradictory.

Calcium Oxalate↗
PubMed1983

[Urinary tract infection in patients with calculi].

The authors review a series of 2,475 cases of patients operated for renal calculi and select 843 files in which the bacteriological study was performed. E. coli is the most common organism (29.8%) compared with Proteus which infects 21% of patients. 71.5% of the patients were infected. Bilateral calculi are the most heavily infected. Kidneys containing calculi which were subjected to a complex operation involving the parenchyma (nephrotomies) were the most difficult to disinfect, even in the absence of recurrence. Conversely, in the absence of recurrence, simple operations (pyelotomy, partial nephrectomy) provide disinfection in the majority of cases. In the authors' series, E. coli remains the organism most frequently encountered, even in cases of recurrence. Proteus and Pyocyanicus are the most difficult organisms to eradicate.

Female↗
PubMed1984

[Statistical analysis on 1,500 urinary calculi by using microcomputer].

In our laboratories, more than 1,500 urinary calculi have been analyzed by infrared spectroscopy. These data were statistically analyzed by microcomputer. The most frequent type was calcium oxalate combined with calcium phosphate, followed by pure calcium oxalate and magnesium ammonium phosphate combined with calcium phosphate. In particular, the composition of magnesium ammonium phosphate combined with calcium phosphate increased as compared with that four years earlier. Four years ago, we spent one month to statistically analyze 300 urinary calculi. But in this study, only sixteen days was required to analyze 1,500 urinary calculi by using a microcomputer.

Adolescent↗
PubMed1984

[A bacteriological study on urinary calculi associated with infections].

There are difficult problems in the management of urinary calculi associated with infections. Stones associated with infections are not only infection stones such as struvite stones, but also other kinds of stones such as calcium oxalate. Therefore, from practical view points, bacteriological studies should be carried out on urinary calculi associated with infections as a whole. We investigated 120 cases of urinary calculi associated with infections with special reference to bacteria on the stone surface, within the stone, compositions of the stone and permeation of an antibiotic into the stone. Proteus was isolated most frequently from the urine, followed by E. coli and Pseudomonas. These bacteria were isolated from the stone surface, although the incidence of Proteus mirabilis was higher than that in the urine. Bacteria were isolated in 25 of the 33 specimens of the inside parts and in 12 of the 12 stones of MAP and MAP plus other components. Proteus mirabilis was found in 7 of the 12 stones. Bacteria were isolated from the inside of 9 of the 16 stones of CaP and CaP plus other components and Proteus mirabilis was found in 6 of these 9 cases. Pseudomonas was isolated in 2 out of the 7 stones of CaP plus CaOX and its growth was seen in 5 specimens. The incorporation of an antibiotic, Cefmetazole, into the stone differed greatly with each stone. There were some cases in which the concentration of Cefmetazole in the inside was less than 5% of that in the outside. Stones may function as a sanctuary for organisms and may protect these organisms.

Adult↗
PubMed1982

Composition of urinary calculi collected in the Durban area.

Three hundred urinary calculi were collected in the Durban area during the period August 1979--August 1980. Analysis by the X-ray diffraction method showed that their composition is generally similar to that found in the USA and UK. The incidence of uric acid, present in 17% of the calculi, is higher than that found overseas. There is a significantly higher incidence of calcium oxalate in calculi from Indians (83% v. 70% in Whites) while there is a significantly higher incidence of urinary apatite in Whites (35% v. 21% in Indians).

Black or African American↗
PubMed1982

[Search for a new rinsing solution for the local lysis of calcium-containing urinary calculi].

Due to improved rinsing techniques local chemolitholysis is again becoming more important. Good result good results in the local chemolysis of phosphate calculi (calculi caused by remains of Struvit) with Renacidin and other rinsing solutions (Fam, Rossier, Gittes, Jacobs, Smith, Royle, Nemoy, Stamey) have led to a revival chemolitholysis (Alken) in the last 4--5 years, however only in the case of phosphate calculi, which account for 60--80%, cannot be dissolved by Renacidin, as is explicitly pointed out by the manufacturer. The experiments carried out by the group headed by Kallistratos and Timmermann in the 60's using rinsing solutions based on EDTA were discontinued, probably because of physiological reservations concerning the chemicals used and the long duration of treatment at physiologically tolerable concentrations and pH values. In order to extend the range of rinsing solutions to be tested, we tested new substances, including some which complex not only the anion (oxalate) but also the cation (Ca). Alternating treatment with oxalate binding and Ca binding rinsing solutions has been found to give particularly good results.

Calcium Oxalate↗
PubMed1981

[Removal of ureteral calculi transurethrally with special reference to the so-called "indwelling Zeiss loop" (author's transl)].

In 1628 patients with ureteral calculi there were 1511 (92,81%) successful immediate stone extractions (1950--1960) or "delayed" calculi removals by means of the ureteric catheter loop left temporarily in the ureter (1964--1980). 95--98% calculi have been successfully treated since the introduction of the catheter loop designed by Zeiss. Anesthesia, antibiotics and X-ray control were required. Multiple loops were used in 74 patients out of 1408. The procedure is not dangerous if X-ray equipment and instruments are adequate. The immediate stone extraction was successful only in 65% (1965--1960) where as the "delayed" extraction by means of the Zeiss-catheter loop was successful in 95--98%. Less than 5% loop extractions are unsuccessful. The mortality rate was less than 0,15%. The procedure can be repeated without limitation.

Catheters, Indwelling↗
PubMed1981

Ammonium acid urate calculi in a cross-bred yorkshire terrier.

The history, clinical signs and pathological findings are described in a cross-bred Yorkshire Terrier which developed renal failure subsequent to the development of renal calculi. These calculi were found to consist of ammonium urate, a rare form of calculi in non-Dalmatian dogs.

Animals↗
PubMedDate not supplied

[Calculi with large oxalate crystals (1st part)].

This is the introduction to the study of calculi which have large oxalate crystals. Calculi which are divided into three groups according to their other, non-oxalic compounds, which will be studied separately in three consecutive articles. Most of those large crystals are spectral and in spite of the fact that the calculi belonging to any group have the same components, the same formation mechanism and the same fundamental structures, they are not exact replicas of a prototype but, on the contrary, they all show a small difference from the previous and following ones which may lie in the duration of their development, in the amounts of their components or in the distribution of these components within them.

Crystallization↗
PubMed1981

[Surgical treatment of coral calculi in the renal pelvis].

In the years between 1971 and 1979 in the Department of Urological Surgery of the Municipal Weil Emil Hospital in 16 of the 72 coral calculi filling the renal pelvis primary (so-called uric acid) calculi were found to which lytholysis was applied. Fifty-six cases (secondary calculi) were operated, in the majority by conservative surgery (40 cases), 16 patients were nephrectomized. The incidence of coral stones is twice as high in women as in men. Congestion and infections play the major role in their pathogenesis, hypercalciuria is less frequent. Up-to-date possibilities of examination ensure the proper plan of the operation. Complete removal of the stones, abolishment of congestion and infection and postoperative care are very important in the prevention of relapse. In 21 of the 72 cases congenital malformation as was found as a source of congestion. There are various types of conservative operations. Quite often the renal parenchyma is incised, and in this case the peduncle has to be ligated. By cooling the kidney the hypoxic time can be prolonged quite considerably. In the course of the operation the kidney must be made free of stones as the incidence of relapses is high. Analysis of the removed coral stones showed that 68% of them consisted of carbonate-apatite-struvite.

Adult↗
PubMed1980

[Value of dietetics and general nutritional guidelines in the metaphylaxis of urinary calculi].

After a short historical survey the interest of our Socialist state in an optimum nutrition and nutritional education of the citizens is described. The importance of prophylaxis, therapy and metaphylaxis of urolithiasis is proved by the increasing morbidity rate of this disease (1-3%). Out of the series of vitamins above all the vitamin B6 is of importance in the oxalate lithiasis so that a diet rich in vitamin B6 is indicated. Of the quantity elements contained in nutrition calcium, phosphorus and magnesium are significant, wherefore the enteral supply of these elements is to be taken into consideration in the various kinds of urinary calculi. Furthermore, in carriers of calcium oxalate calculi nutrients rich in oxalic acid and in carriers of urinary calculi and in hyperuricaemia, respectively, nutrients rich in purine should be restricted. Adequate tables concerning the vitamin B6, Ca, P, Mg, oxalic acid and purine content of the nutrients are given. The increasing importance of the adiposity of carriers of uroliths is represented with the help of indices of our own urolith dispensary. Finally short references to diet for the 4 most important kinds of uroliths are proposed.

Diet↗
PubMed1980

Urinary tract calculi in man and laboratory animals: incidence, composition, and etiology.

Calculi in the urinary tract is a disease which afflicts not only man, but also experimental animals. The incidence of human stone disease varies widely according to the geographical area. With the advent of sophisticated physicochemical techniques, the elucidation of structure and the quantification of mineral components of urinary calculi have been greatly facilitated. In addition to calcium oxalate and calcium phosphate, more than ten other minerals and a large number of trace elements have been identified to date. Matrix material consists of such macro-molecules as proteins and mucopolysaccharides. The etiology of urinary calculi is varied; diet, drugs, chemicals, bladder implants, infections, metabolic derangements, and environmental influences are some of the factors that can contribute to the pathogenesis of stones. The literature findings reflect the complexity of urolithiasis as a clinicopathological problem.

Animals↗
PubMed1996

Long-term incidence and risks for recurrent stones following contemporary management of upper tract calculi in patients with a urinary diversion.

PURPOSE: The long-term rate of stone recurrence following contemporary minimally invasive management of calculi was determined in patients with urinary diversion and to identify specific risk factors for these recurrences. MATERIALS AND METHODS: We followed for a minimum of 12 months 25 patients (29 renal units) with upper tract calculi associated with urinary diversion, and treated with extracorporeal shock wave lithotripsy and/or percutaneous nephrostolithotomy. The risk of recurrent stones at 5 years was determined by a Kaplan-Meier estimate, while potential risk factors for recurrence were analyzed using a log-rank comparison. RESULTS: Stones recurred in 8 patients (32%) 18 to 61 months (mean 27.0) after treatment. The risk of new stone formation after 5 years was estimated to be 63.3% and was significantly greater in patients with recurrent bacteriuria after treatment. Neither stone history, type of procedure used, stone composition nor radiographic status at completion of treatment significantly influenced this risk. CONCLUSIONS: Contemporary management of upper tract calculi in patients with a urinary diversion is associated with a high recurrence rate, especially among those with recurrent bacteriuria, regardless of whether the patient is initially rendered stone-free. Continued close surveillance and antibiotic prophylaxis seem to be essential in this high risk patient population.

Bacteriuria↗
PubMed1996

Urinary calculi as a late complication of the Indiana continent urinary diversion: comparison with the Kock pouch procedure.

PURPOSE: Although urinary calculi have been frequent late complications of the Kock continent urinary diversion, they have not been regarded as significant problems in patients with the Indiana pouch because of the lack of foreign material present. However, stones developed in a significant percentage of our patients with an Indiana pouch. We investigated the characteristics of stone formation in patients with the Indiana pouch and compared them to those with a Kock pouch. MATERIALS AND METHODS: Detailed clinical courses regarding stone formation were reviewed in 72 patients with a Kock pouch and 54 with an Indiana pouch who had a minimum followup of 12 months. RESULTS: Stones developed in 7 of 54 patients (12.9%) with an Indiana pouch compared to 31 of 72 (43.1%) with a Kock pouch. The incidence gradually increased with longer followup but it was lower in the Indiana than in the Kock pouch group (5-year stone-free rate 84% versus 66%, respectively). Although the stones consisted principally of a mixture of struvite, carbonate apatite and ammonium hydrogen urate, variable amounts of calcium oxalate were identified in 50% of the Indiana pouch calculi. CONCLUSIONS: Not only urinary infections but also metabolic factors were considered to be involved in stone formation within the Indiana pouch. However, the substantially higher rate of stone formation in our Kock and Indiana pouch groups than has been reported in the United States suggested that no or infrequent pouch irrigations in our patients were important risk factors for urinary calculi.

Case-Control Studies↗
PubMed1994

Analysis of urinary calculi.

Urinary calculi are often small (< 5 mg) and can be composed of many very different constituents. The highly variable composition has lead to the development of many different methods of calculi analysis. In general the analytical methods can be divided in chemical and physical methods. Chemical methods are destructive and need several mg of sample. The smallest stones can not be analyzed with chemical methods. Qualitative and semi-quantitative chemical analysis methods are not accurate and can lead to clinical significant errors. Quantitative, instrumental, chemical analysis is accurate and makes no clinical significant errors, but these consume too much sample. None of the chemical methods of stone analysis makes it possible to distinguish the mineral constituents with similar chemical composition, e.g. the calcium phosphates, from one another and they usually can not identify "unexpected" stones. Physical methods need less sample than chemical methods and physical methods can distinguish the different minerals in the stones. Thermal analysis can give quantitative results but needs relatively much sample. Optical methods can analyze a few grains of stone but gives only qualitative results. Both methods can not be used to analyze an "unexpected" stone. Best suited methods for the analysis of calculi are X-ray diffractometry and IR spectroscopy. X-ray diffractometry can detect crystalline minerals in low concentrations. IR spectroscopy can detect both crystalline and amorphous minerals. Both methods can be used for semi-quantitative stone analysis and can analyze less than one mg of stone sample. X-ray diffractometry and IR spectroscopy are also the best methods to identify "unexpected" stone constituents.

Calcium Oxalate↗
PubMed1993

Studies on structure of calcium oxalate monohydrate renal papillary calculi. Mechanism of formation.

A scanning electron microscopy study of the ultrastructure of 18 calcium oxalate monohydrate papillary calculi was performed with the purpose of establishing the main steps in calculus formation. It is concluded that these calculi originate in a "core" located near the central part of the calculus. Significant quantities of organic matter as well as calcium phosphates can be found in the "core" and at the surface of adhesion to the papilla and, in some cases, fibers and calcified tubules can also be found in the contact zone. In no case did this material affect the crystalline structure of the calculi, indicating that its formation follows the calculus genesis. The study of the compact columnar zone revealed that its formation starts in a practically continuous surface formed by organic matter and crystals that surround the core. This layer favors the growth of oriented calcium oxalate monohydrate crystals upon it. Based on these observations, a feasible mechanism of papillary calcium oxalate monohydrate calculus formation is proposed.

Adolescent↗