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PubMed1990

Renal calculi in army aviators.

A study of U.S. Army active duty aviators was done using the Aeromedical Epidemiology Data Repository (AEDR) for the period of January 1984 through December 1987 to determine the incidence of renal calculi in this population. Age-specific rates were found to be highest in the 30-54 year age group. The overall annual incidence was determined to be 4.7/1000 population of white male aviators. After standardization to the 1960 U.S. white population, the incidence in aviators was found to be 2.2/1000, almost double that of a Rochester, MN male population (1.2/1000). The aviation environment may predispose Army aviators to dehydration and play an etiologic role in the genesis of renal calculi. Medical evaluation, treatment, and administrative disposition of Army aviators with renal calculi are also briefly discussed.

Adult↗
PubMedDate not supplied

[Analysis of the composition of 2700 urinary calculi examined by infrared spectrophotometry, 1979-1989].

Two thousand seven hundred samples, received as urinary calculi, in a Turin based laboratory, in the period between March 1979 and February 1989, were examined by infrared spectroscopy to identify components even of difficult characterization: a special procedure was used and it is described. Knowing the composition of each calculus, a comparison was made between the incidence of each compound in the first 1500 samples (1979-1984) and in the remaining 1200 ones (1984-1989). Besides an increase in calcium oxalate as main component, a marked reduction in incidence of struvite was found in the calculi belonging to the second period of observation. The possible interference in calculi composition by various therapy for renal infection is discussed.

Calcium Oxalate↗
PubMed1989

[Correlation of the cause and composition of renal calculi. Value of morphologic and infrared analysis].

The morphological and infrared spectrophotometric analysis of the urinary stones of 300 patients have been reported in this article. Calculi are classified into six morphological types with their corresponding mineralogical natures. The type I (whewellite or C1) is pure in 18 p. cent of lithiasis, more often present in the center than on the surface, with hyperoxaluria in 81 p. cent. Calculi linked to piridoxilate intake (3 p. cent) have this composition. The type II (weddellite or C2) rarely pure, often associated with calcium phosphate are present in 47 p. cent of lithiasis, more often on the surface than in the center, and linked to hypercalciuria in 70 p. cent. The oxalates (C1 plus C2) are the most frequent components of calculi (75 p. cent). The type IIIa and IIIb (anhydrous and dehydrated uric acid) are pure in 8 p. cent, mixed in 6 p. cent; due to hyperuraturia in 55 p. cent, due to urinary acid pH in 60 p. cent. The type IVa (carbapatite) is pure in 5 p. cent, mixed in 26 p. cent, linked to hypercalciuria in 40 p. cent. The types IVb and IVc (struvite plus carbapatite) are present in 12 p. cent, due to urinary infection (90 p. cent), linked to proteus (70 p. cent). The type V (cystine) is rare, linked to hypercystinuria. The type VIa (1 p. cent) is made of proteins. The type VIb (2 p. cent) is composed of medications (triamterene, glafenine, antrafenine).

Humans↗
PubMed1989

[Investigation on the composition and structure of 400 urinary calculi].

400 urinary calculi have been analyzed by chemical and physical methods, namely chemical qualitative analysis, metallic elements spectrometry, X-ray diffraction, infrared spectroscopy, thermographimetric analysis, polarizing microscopy, scanning electron microscopy, etc. Further understanding of the correlation between the structure and the composition of calculi was achieved, which may be helpful in inquiring the formation of urinary calculi.

Calcium↗
PubMed1988

[An electron paramagnetic resonance study of 4 salivary calculi treated in an ionized oxygen atmosphere].

Four salivary calculi and synthetically prepared hydroxyapatite, tricalcium phosphate and B-type carbonated fluorapatite or hydroxyapatite were treated under excited oxygen atmosphere. All these samples were studied by Electron Spin Resonance at 100 K. The presence of paramagnetic ozonide ions was observed only in the salivary calculi and in the hydroxyapatite. This indicates that the dominant apatite phase in salivary calculi is weakly carbonated hydroxyapatite.

Apatites↗
PubMed1987

[Therapy of bladder calculi--trends and results of a mainly transurethral oriented clinic].

From 1975 to 1985 519 patients with urinary calculi were treated in the Urologic Clinic of the Berlin-Buch Hospitals. 57.6% of them were treated by lithotripsy and TUR-P, 14.8% by lithotripsy alone, 11.8% by stone removal and transvesical adenomectomy and 15.8% by suprapubic cystotomy only. The diagnosis of the four forms of therapy is described. The trend in the conception of treatment goes to the treatment of calculi transurethrally in combination with the simultaneous removal of the obstruction of the outflow from the urinary bladder. Since October 1985 the electrohydraulic lithotripsy has been used. Up to 1985 in 218 patients urinary calculi were crushed by means of the device Urat-1. In 190 patients (87.3%) the lithotripsy was carried out in combination with other therapeutic measures, in 153 (70.2%) a transurethral resection of the prostate gland and in 28 patients (12.9%) other transurethral interventions were performed. Postoperatively, in 7 patients complications occurred (3.2%), perforations of the urinary bladder were not seen. Taking into consideration the whole number of patients, it is reported on the advantages of the use of the electrohydraulic lithotripsy by means of the apparatus Urat-1 as an uncomplicated technique easily to be learned, which excellently may be combined with simultaneous transurethral interventions.

Aged↗
PubMed1987

Computer-aided infrared analysis of urinary calculi.

We have created a library of 497 digitized infrared spectra of 58 components of urinary calculi and of their usual binary and ternary mixtures. We tested the operation of the "Birsy" search program (Bruker Analytische Messtechnik) with this library for the interpretation of infrared spectra of 50 urinary calculi, selected from both classical and difficult cases. This program correctly identifies the two first components 98% of the time and the third (minor) component 70% of the time. Using this program, those without training or experience in infrared analysis can routinely use the infrared method of analysis of urinary calculi.

Humans↗
PubMed1986

[Nonspecific pyelonephritis and the formation of urinary calculi in urogenital tuberculosis].

The course of urogenital tuberculosis is complicated by unspecific bacterial infections of the urinary tract and nephrolithiasis. Among 605 patients with bacteriological or histological verified urogenital tuberculosis, 122 patients (20%) developed unspecific bacterial urinary infection--commonly caused by E. coli, proteus and pseudomonas--and 57 patients (9.4%) showed nephrolithiasis. In 42% of the lithiasis patients an urinary tract infection simultaneously occurred. 22 calculi are analyzed by the combined crystal-optical and x-ray-diffraction method with following results: 9 X struvite/carbonate apatite, 6 X calcium phosphate, 7 X calcium oxalate. The texture of 12 calculi was investigated on thin sections by polarization microscopy and a high concentration of organic material was found in both calcium oxalate and struvite/carbonate apatite calculi.

Bacteria↗
PubMed1986

[Transurethral ureteroscopic removal of ureteral calculi].

Rigid ureteroscopy was used for transurethral removal of ureteral stones. Calculi were extracted under direct vision using flexible grasping forceps or a stone basket. If the size of the stone precluded the use of these techniques, we disintegrated the stone using an electro-hydraulic lithotriptor (EHL) or ultrasonic lithotriptor (USL). Between January, 1985 and October, 1985, 35 ureteroscopic procedures were performed for removal of ureteral stones. In 27 cases (77%) the stone was removed successfully. All stones could be removed in mid and lower ureter. However, in upper ureter, the success rate was only 50%. In 8 instances, ureteroscopy failed to remove the ureteral calculus and 6 underwent percutaneous nephrolithotomy, 2 open surgery. Of the ureteral stones, 12 were removed with grasping forceps or a basket manipulation. EHL and USL were used successfully to remove calculi in 15 cases. To make smooth passage of the ureteroscope, a 6F UPJ occlusion balloon catheter was introduced into the ureter and the balloon was inflated in the intramural ureter for 24 hours preoperatively. We have found this to be a useful procedure for smooth passage of the ureteroscope. Most common complication of ureteroscopic stone removal was fever (29%). In 1 case, the ureter was penetrated by the scope. The patient was treated with an indwelling ureteral catheter for 2 weeks. After the catheter was removed, an excretory urogram demonstrated normal ureter without extravasation or obstruction. We conclude that ureteroscopic stone removal can be done safely with careful passage of the scope and careful manipulation of calculi.

Adult↗
PubMed1979

[The care of patients with urate calculi].

In patients with urate calculi as well as in endangered persons--formation of calculi in the anamnesis, excretion of calculi or sand, urate diathesis--a regular permanent control and care is also of importance as in every other patient suffering from a chronic renal disease. It would be desirable to establish the actual frequency of urolithiasis by introducing the duty of notification. On this way a network of care units could be established within the leading regional institutions, which would further the elaboration of unitary directives for the examination and treatment of patients.

Allopurinol↗
PubMedDate not supplied

Percutaneous nephrostolithotomy vs open surgery for renal calculi. A comparative study.

To evaluate the impact of the percutaneous removal of renal calculi we compared 41 patients who had undergone open renal surgery to 88 patients who had a one- or two-stage percutaneous nephrostolithotomy for symptomatic urolithiasis. The two groups were similar with regard to stone size, stone location, treatment success, and complication rates. However, for patients with calculi 2.5 cm or smaller in diameter, the percutaneous procedure resulted in lower postoperative morbidity, more rapid convalescence, less hospital cost, and greater patient satisfaction. For patients with calculi larger than 2.5 cm in diameter, the percutaneous approach was slightly more expensive than open surgery but resulted in a markedly shortened convalescent period. In our experience, percutaneous nephrostolithotomy performed in a single stage under assisted local anesthesia was the most efficacious and least expensive of the percutaneous approaches.

Adult↗
PubMed1985

[Formation of the staghorn calculi].

To study the process of formation of staghorn calculi, 58 patients with staghorn calculi were evaluated clinically and the removed stones were studied architecturally. Of 35 patients with infection stones composed of struvite and/or apatite in the nuclei as well as peripheral layers, 18 had identified predisposing factors related to infection. Of 13 patients with infection stones containing calcium oxalate in the nuclei, 7 had predisposing factors of infection but only 2 had metabolic disorders. The patients with infection stones who had no predisposing factors may have transient or subclinical abnormalities. Initial stone formation of oxalate may also be one of the predisposing factors of infection. Most of the patients with staghorn calculi composed of uric acid, oxalate and cystine, had metabolic disorders related to these substances. Large numbers of bacteria and large amounts of organic matrix were found extensively within infection stones and were thought to be important components as well as crystals. Metabolic stones contained little matrix. In this case crystal aggregation is thought to play the most important role in stone formation.

Adolescent↗
PubMed1979

[Compliance and active cooperation of patients in preventing recurrence of urinary calculi].

An anonymous questioning of 200 patients with urinary calculi concerning the observation of the general and special measures of the metaphylaxis of urinary calculi resulted in the fact that in particular the measures of the general metaphylaxis (bodily movement, diet, dilution of the urine) are not or only parlty obeyed by a large part of the patients. The examinations show that for the improvement of the understanding of the disease and the behaviour of the patients concerning their health further on a great attension must be paid to the quality of the information by the physician and to the communication between physician and patient. An insufficient cooperation of the patients in the metaphylaxis of the urinary calculi would call in question the effectivity of all efforts and measures concerning the prevention of relapses.

Adolescent↗
PubMed1979

[Somatic parameters in patients with urinary calculi and their relationship to age, sex and kind of calculus].

In the present investigation in 515 carriers of nephroliths (311 males and 204 females) age, sex, type of constitution, body weight, physical load and blood pressure are set in relation to the various kinds of calculi. Here it was revealed that males more frequently fall ill with nephrolithiasis than females, that there exist certain age peaks, the pycnic typ of constitution preferredly appears in female carriers of calculi and the athletic type in male ones, the majority of all examined patients had in comparison to the normal an increased body weight, and a very large proportion of persons with only insignificant physical load is found among the carriers of calculi. The result of the relations of blood pressure was that only half of all patients with urolithiasis examined had a normotonic blood pressure.

Age Factors↗
PubMed1974

Bilateral renal calculi.

Bilateral renal calculi were present in 114 (10.7%) of 1,070 cases of proved urinary calculus admitted to the Urological Department of the General Hospital, Kuala Lumpur, during the period November 1968-May 1973. The management of bilateral renal calculi is discussed with reference to the first 100 cases in this series. The introduction of renography has greatly facilitated the decision as to which kidney should be operated on first. The management of patients with and without uraemia is discussed and the use of the modified V and V-Y incisions for the removal of staghorn calculi is described. Complications and results are briefly reviewed.

Adult↗
PubMed1970

Renal calculi.

The pathogenesis of renal calculi is reviewed in general terms followed by the results of investigation of 439 patients with renal calculi studied by the author at Toronto General Hospital over a 13-year period. Abnormalities of probable pathogenetic significance were encountered in 76% of patients. Idiopathic hypercalciuria was encountered in 42% of patients, primary hyperparathyroidism in 11%, urinary infection in 8% and miscellaneous disorders in 8%. The incidence of uric acid stones and cystinuria was 5% and 2% respectively. In the remaining 24% of patients in whom no definite abnormalities were encountered the mean urinary magnesium excretion was less than normal. Of 180 patients with idiopathic hypercalciuria, only 24 were females. In the diagnosis of hyperparathyroidism, the importance of detecting minimal degrees of hypercalcemia is stressed; attention is also drawn to the new observation that the upper limit of normal for serum calcium is slightly lower in females than in males. The efficacy of various measures advocated for the prevention of renal calculi is also reviewed. In the author's experience the administration of thiazides has been particularly effective in the prevention of calcium stones. Thiazides cause a sustained reduction in urinary calcium excretion and increase in urinary magnesium excretion. These agents also appear to affect the skeleton by diminishing bone resorption and slowing down bone turnover.

Diet Therapy↗
PubMed1977

[Infrared spectroscopy in the quantitative determination of urinary calculi constituents (author's transl)].

Infrared spectroscopy of urinary calculi can be used for the quantitative determination of the major constituents in mixed stones; the method is simple and consists in area-measurements of specific absorption peaks of the spectrum of each compound. In the area-measurement method the average error is +/- 2,5% in calcium-oxalate-apatite and +/- 2% in ammonium magnesium phosphate-carboapatite mixtures; within these limits the calculus matrix do not affect significantly the value of areas. An investigation of 64 mixed renal stones shows that in 57% of the samples, apatite is present in the nucleus; uric acid and calcium-oxalate are the most frequent superficial compounds, while the external layer of ammonium magnesium phosphate and the mixture uric acid-calcium phosphate are rare events. In calcium-oxalate-apatite and ammonium magnesium phosphate-carboapatite calculi the quantitative composition of the nucleus and the external layer differ significantly. The proposed method of analysis of internal and external structures in renal calculi can be useful for the study of etiology, for the prevention and the treatment of urolithiasis.

Humans↗
PubMed1984

Silicon dioxide calculi in humans in the absence of silicate antacid medication.

The occurrence of silicon dioxide in human urinary calculi is more common than generally believed. During a 3 year study we have analyzed about 750 human urinary calculi using the scanning electron microscope and x-ray crystallographic methods. Silicon dioxide of the alpha quartz variety was found to be the principal constituent in calculi from 5 male patients. Some of the patients were recurrent stone formers and 1 patient has previously produced a silicon dioxide calculus. In none of the 5 cases was there any history of gastric disorders or of any ingestion of antacids in the form of magnesium trisilicate. Some of the silica particles have a morphology typical of glacial sand.

Adult↗