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Do not treat staghorn calculi by extracorporeal shockwave lithotripsy alone!

A review of 84 patients with triple phosphate (staghorn) calculi treated by extracorporeal shockwave lithotripsy (ESWL) revealed a 67% stone clearance at 6 months. Classification of calculi according to morphology showed a variation in stone clearance from 47 to 82%. A significant number of patients developed complications (25%) or required additional procedures (27%). ESWL monotherapy is not a suitable treatment option for most patients with staghorn calculi.

Adolescent↗

Does ureteral manipulation improve the effect of extracorporeal electromagnetic shock wave treatment on impacted ureteral calculi?--an experimental study.

OBJECTIVE: We used an experimental study to evaluate the effects of ureteral manipulation on the disintegration of impacted ureteral calculi. METHODS: Fifteen urinary calculi were divided into 3 groups according to the type of ureteral manipulation. Group 1: control group, no manipulation; group 2: bypass catheterization, and group 3: below irrigation in porcine ureter. Each calculus was subjected to 500 shock wave pulses with 0.28 mJ/mm2 power density by a Siemens Lithostar II lithotriptor. RESULTS: The successful disintegration ratio for calculus sizes less than 4 and 2 mm was 79.4 +/- 13.1 and 42.2 +/- 7.5% (group 1), 82.3 +/- 5.2 and 43.5 +/- 2.4% (group 2) and 84.3 +/- 17.3 and 49.7 +/- 14.6% (group 3). There was no statistical difference among the 3 groups by Anova and the Kruskal-Wallis test. CONCLUSION: The ureteral manipulation of impacted ureteral calculi was unable to improve stone disintegration by shock wave.

Animals↗

Prognosis after extracorporeal shock wave lithotripsy of radiopaque renal calculi: a multivariate analysis.

To obtain a better understanding of the prognostic factors influencing treatment outcome after extracorporeal shock wave lithotripsy (ESWL), a multivariate logistic analysis of the data from 246 patients has been undertaken. All of the patients were treated with the Dornier lithotriptor HM-3 for radiopaque renal calculi. Treatment success was defined as stone-free within 3 months of one ESWL session and without adjuvant measures after ESWL. In a first analysis, 210 patients with solitary and multiple calculi without adjuvant measures before ESWL were studied. Of 210 patients, 141 (67%) were free from stones after 3 months). Significant influences on the success rate were body mass index and stone number. In a second analysis only those 160 patients with solitary calculi were considered. In this group, age, body mass index, stone location, stone burden and serum calcium significantly influenced the prognosis. When patients with adjuvant measures were added to the analysis an increasing prognostic importance of the stone burden was seen. In patients with a small to medium stone burden (< 4.0 cm3), the number of stones seemed to be more important than the stone burden. Patients appear to have the best chance for successful ESWL when their body mass index is between 20 and 28, their age is between 40 and 60 years, their stones are in the renal pelvis and solitary, the stone burden is < 1.0 cm3, and when their serum calcium is normal.

Adult↗

Infrared analysis of renal calculi: a comparison with conventional techniques.

The analysis of renal calculi is an oft-neglected corner of clinical biochemistry. This study compares results obtained by the conventional qualitative methods with results from quantitative and infrared methods and also investigates the role of x-ray diffraction analysis. Infrared spectroscopy, using a KBr disc technique, was found to be the single most useful method, being fast, simple to learn, using little sample, and in general permitting positive identification of most of the components found in renal calculi. A major advantage is that this method has approximately equal sensitivity for oxalate and phosphate, unlike the wet chemical methods. Infrared analysis is also useful in identifying the spurious materials sometimes submitted as renal calculi. X-ray diffraction analysis is not a technique that is routinely available, but it does provide information not given by other methods, eg, distinguishing Ca(COO)2 . H2O from Ca(COO)2 . 2H2O. For complete analysis a combination of methods was adopted; carbonate is tested for using a microchemical technique, calcium, magnesium, and phosphate are quantitated by routine methods, and infrared analysis is used to detect oxalate and organic components. It must be emphasised that any method is only as good as the sample used, and different areas of the calculus must be analysed separately if useful results are to be obtained.

Carbonates↗

Salivary calculi: ultrastructural morphology and bacterial etiology.

Ultrastructural morphology of 16 salivary calculi was studied by means of transmission and scanning electron microscopy. The external surface was mostly globular or coarse, and on high magnifications and features could be divided into four main groups: a) amorphic calcified deposits covering extensive areas, b) other areas covered with crystals in a variety of arrangements, c) heavy accumulations of calcified rod-like and filamentouslike microorganisms, and d) platelet crystals in juxtaposition to calcified microorganisms in several areas. In most calculi the split area was found to be laminated. It is suggested that microorganisms have an important role in the formation and growth of salivary calculi.

Bacteria↗

Pharmacologic expulsive treatment of ureteral calculi.

OBJECTIVE: To evaluate the role of nifedipine and the alpha(1)-adrenoreceptor antagonists tamsulosin, terazosin, and doxazosin in the expulsive treatment of ureteral calculi. DATA SOURCES: Literature was searched via MEDLINE (1966-February 2006) with subsequent bibliographic review. MeSH headings included ureteral calculi, nifedipine, doxazosin, and adrenergic alpha-antagonists. Key terms were ureteral calculi, nifedipine, tamsulosin, terazosin, and doxazosin. STUDY SELECTION AND DATA EXTRACTION: Trials evaluating nifedipine, tamsulosin, terazosin, and doxazosin for expulsion of ureteral stones were reviewed. All were published in English-language, peer-reviewed journals. DATA SYNTHESIS: Several trials have evaluated the effects of nifedipine and tamsulosin on ureteral stone passage rates and mean time to stone passage in stones no larger than 15 mm. In 28 day trials, the rates of ureteral stone passage were 35-70% in the control groups compared with 77.1-80% in patients treated with nifedipine and 79.3-100% in patients treated with tamsulosin. Average number of days to stone passage in the control groups was 4.6-20, and the time to stone passage was only 5-9.3 days in patients receiving nifedipine and 2.7-7.9 days in those receiving tamsulosin. The stone passage rates and time to stone passage appeared to be similar in one trial that compared tamsulosin with terazosin and doxazosin. Limited data suggest that these agents may have a role as adjuncts to shock wave lithotripsy. Adverse drug reactions were uncommon. CONCLUSIONS: Nifedipine, tamsulosin, terazosin, and doxazosin are safe and effective options in enhancing ureteral stone expulsion in selected patients with uncomplicated presentations.

Adrenergic alpha-1 Receptor Antagonists↗

Extracorporeal shockwave lithotripsy versus ureteroscopy for distal ureteric calculi: efficacy and patient satisfaction.

OBJECTIVE: We compared the efficacy of extracorporeal shock wave lithotripsy (ESWL) and ureteroscopy (URS) for the treatment of distal ureteral calculi with respect to patient satisfaction. MATERIALS AND METHODS: This is a prospective study where a total of 212 patients with solitary, radiopaque distal ureteral calculi were treated with ESWL (n = 92) using Dornier lithotriptor S (MedTech Europe GmbH) or URS (n = 120). Patient and stone characteristics, treatment parameters, clinical outcomes, and patient satisfaction were assessed for each group. RESULTS: The 2 groups were comparable in regard to patient age, sex, stone size, and side of treatment. The stone-free status for ESWL and URS at 3 months was 81.5% and 97.5%, respectively (p < 0.0001). In addition, 88% of patients who underwent ESWL versus 20% who underwent URS were discharged home the day of procedure. Minor complications occurred in 3.3% and 8.3% of the ESWL and URS groups, respectively (p = 0.127). No ureteral perforation or stricture occurred in the URS group. Postoperative flank pain and dysuria were more severe in the URS than ESWL group, although the differences were not statistically significant (p = 0.16). Patient satisfaction was high for both groups, including 94% for URS and 80% for ESWL (p = 0.002). CONCLUSIONS: URS is more effective than ESWL for the treatment of distal ureteral calculi. ESWL was more often performed on an outpatient basis, and showed a trend towards less flank pain and dysuria, fewer complications and quicker convalescence. Patient satisfaction was significantly higher for URS according to the questionnaire used in this study.

Adolescent↗

Computed tomography of urinary calculi.

Computed tomography (CT) was used in the evaluation of nine patients with nonopaque calculi in the upper urinary tract. In each case the calculus was identified as a very high density object (370-586 Hounsfield units) with calcium oxalate and cystine stones having somewhat higher attenuation values than uric acid or xanthine stones. The differentiation between calculi and other "radiolucent" filling defects was readily made since calculi had much higher attenuation values than blood clot or neoplasm. CT of the upper urinary tract may obviate the need for more invasive procedures such as retrograde pyelography when nonopaque filling defects require differentiation.

Adult↗

Computed tomographic analysis of urinary calculi.

Excised urinary calculi were subjected to computed tomographic (CT) scanning in an attempt to determine whether CT attenuation values would allow accurate analysis of stone composition. The mean, maximum, and modal pixel densities of the calculi were recorded and compared; the resulting values reflected considerable heterogeneity in stone density. Although uric acid and cystine calculi could be identified by their discrete ranges on one or more of these criteria, calcium-containing stones of various compositions, including struvite, could not be distinguished reliably. CT analysis of stone density is not likely to be more accurate than standard radiography in characterizing stone composition in vivo.

Calcium Oxalate↗

Percutaneous removal of caliceal calculi.

Of 170 patients who underwent percutaneous nephrostolithotomy, 61 had stones located in a calix. Direct access to the calix containing the calculus optimizes removal. Special maneuvers during and after percutaneous stone removal (e.g., parallel-tract push and loop snare retrieval system) facilitate removal of caliceal calculi from more difficult locations; 46% of patients with caliceal calculi required adjuvant radiologic techniques. Complete calculus removal was achieved in 90% of patients with caliceal calculi.

Adult↗

Detection of ureteral calculi in patients with suspected renal colic: value of reformatted noncontrast helical CT.

OBJECTIVE: The purpose of this study was to determine the value of reformatted noncontrast helical CT in patients with suspected renal colic. We hoped to determine whether this technique might create images acceptable to both radiologists and clinicians and replace our current protocol of sonography and abdominal plain film. SUBJECTS AND METHODS: Thirty-four consecutive patients with signs and symptoms of renal colic were imaged with both noncontrast helical CT and a combination of plain film of the abdomen and renal sonography. Reformatting of the helical CT data was performed on a workstation to create a variety of reformatted displays. The correlative studies were interpreted by separate blinded observers. Clinical data, including the presence of hematuria and the documentation of stone passage or removal, were recorded. RESULTS: Findings on 18 CT examinations were interpreted as positive for the presence of ureteral calculi; 16 of these cases were determined to be true positives on the basis of later-documented passage of a calculus. Thirteen of the 16 cases proved to be positive were interpreted as positive for renal calculi using the combination of abdominal plain film and renal sonography. The most useful CT reformatting technique was curved planar reformatting of the ureters to determine whether a ureteral calculus was present. CONCLUSION: In this study, noncontrast helical CT was a rapid and accurate method for determining the presence of ureteral calculi causing renal colic. The reformatted views produced images similar in appearance to excretory urograms, aiding greatly in communicating with clinicians. Limitations on the technique include the time and equipment necessary for reformatting and the suboptimal quality of reformatted images when little retroperitoneal fat is present.

Adult↗

Ureteral calculi: diagnostic efficacy of helical CT and implications for treatment of patients.

OBJECTIVE: The purpose of this study was to evaluate whether unenhanced helical CT of the abdomen and pelvis, supplemented as necessary with delayed enhanced CT of the pelvis, is sufficient for urologists to treat patients with acute renal colic. MATERIALS AND METHODS: CT scans from 99 patients were analyzed retrospectively for the presence, size, and location of ureteral calculi and the presence and severity of secondary signs of obstruction. Clinical follow-up was analyzed by reviewing charts, directly communicating with patients, and reviewing surgical reports. Clinical information was correlated with CT findings. RESULTS: The findings of 51 CT scans were positive for calculi, and the findings of 48 were negative for calculi. The findings from two CT scans were false-positive, and none of the findings were false-negative. The sensitivity, specificity, and accuracy of helical CT were 100%, 96%, and 98%, respectively. A significant difference in stone size was found between patients who were treated conservatively (3.3 +/- 1.3 mm) and patients who underwent a urologic procedure (7 +/- 6.2 mm) (p < .01) and between patients in whom successful ureteral stent placement was the sole intervention (3.9 +/- 2.8 mm) and patients in whom initial stent placement failed and who then underwent a second urologic procedure (7.4 +/- 3 mm) (p < .05). We found no statistically significant difference between the conservatively and interventionally treated groups with respect to stone location. The presence and severity of secondary signs of obstruction were not significantly different between the two groups. CONCLUSION: Stone size alone was found to correlate with patient treatment. Stone location and the presence and severity of secondary signs of obstruction did not affect patient treatment. Because the degree of obstruction and relative renal function are not relevant to the initial treatment of patients with ureteral stone obstruction, CT is adequate for both diagnosis and treatment.

Acute Disease↗

[Diagnosis of ureteral calculi using ultrasonography, intravenous urography and unenhanced helical computed tomography].

INTRODUCTION: The pain in the loins is usually the consequence of renal colic caused by small ureteral calculi. ULTRASONOGRAPHY: Ultrasonography is an efficient tool in the detection of calculi in the pyelocalyx system, but it may not be sufficient for the area of renal pelvis and ureter, as wll as for the ureter and the ureterovesical junction. INTRAVENOUS UROGRAPHY: Radiolucent stones, dilatation of the ureter and of the pyelocalyx system were identified on the urogram, which are common signs of ureter calculosis. Defects in the contrast can be caused by blood clots and papillary or malignant tumors of the ureter, thus causing a differential diagnosis problem. UNENHANCED HELICAL COMPUTED TOMOGRAPHY: Noncontrast spiral CT is useful for detection fo calculi as small as 3mm. It can identify their localization and size without enlargements. The primary and secondary CT signs also confirm the established diagnosis. CONCLUSION: The noncontrast spiral CT is a highly precise method for assessment of kidney pain. It is a realiable and rapid diagnostic modality for the detection of urinary stones which differentiates them from blood clots, tumors, air and other factors which create a differential diagnosis problem.

Humans↗

Phytate acts as an inhibitor in formation of renal calculi.

The aim of this study was to assess the inhibitory action of phytate in formation of renal calculi. Hypertension (induced by nicotine) combined with hypercalcemia (induced by D vitamin) was used to induce calcification in renal tissue in male Wistar rats that were fed a purified phytate free diet. Phytate non-treated rats developed significant calcium deposits in kidneys and papillae, as well as in kidney tubules and vessels, whereas calcium deposits were absent in control and phytate treated rats. Fragments of hydroxyapatite (HAP) calculi exhibited the capacity to induce the growth of calcium salts on their surfaces. Presence of 1.5 mg/L of phytate in the synthetic urine inhibited the formation of calcium oxalate monohydrate on HAP renal calculi in normocalciuric conditions. The findings show that the action of phytate as a crystallization inhibitor takes place both in the intrapapillary tissue and urine.

Animals↗

Analysis of urinary calculi; a quality control programme.

Results of the first Nordic quality control programme on urinary calculi are described. The programme included nine specimens, nine components and 57 laboratories participated. Most of the specimens were mixtures of selected human calculi. Of the laboratories, 67% used a binary scale for the results("qualitative"); 80% of the laboratories were unable to carry out the analysis on 10 mg material or less. For most components false positive results were rare. Oxalate and calcium (II), however, were exceptions. Results on "mixed stones" were unsatisfactory; frequently 20% of the results were wrong. The fraction of false negative results is 0.10 for cystine and urate, and is generally higher for other components. No difference between the reliability of infrared spectrometry and of wet chemistry is observed. An ordinary internal quality control scheme is suggested to facilitate improvements of the routine analytical performance. Some ideas of the analytical strategy are discussed. The drawbacks of results from a binary scale are stressed, and it is suggested that the examination of urinary calculi be carried out using techniques which give results on continuous scales. At the same time the number of components for analysis in the routine programme may be reduced.

Ammonia↗

Infection-induced urinary calculi and renal failure.

During 1974-1984 altogether 481 patients were treated for end-stage renal disease (ESRD). Eight patients, five women and three men, with chronic pyelonephritis as the primary cause of ESRD, had staghorn urinary calculi as a predisposing factor for renal failure. These eight patients were studied retrospectively concerning epidemiological and bacteriological aspects, the treatment of the stone disease, and the development of uraemia. Anatomical and metabolic abnormalities such as bladder outlet disturbances, primary hyperparathyroidism, phenacetin abuse or metabolic stone disease were found in six patients. The women had all been infected with Proteus mirabilis, whereas the men had been infected with various microorganisms. The average time taken for the development of ESRD, estimated from the first sign of renal impairment, was 7.4 +/- 2.9 (SD) years. Five patients had died before this study commenced. One of the patients still alive was on dialysis treatment. Two patients who were doing well without dialysis were stone free and had sterile urine after successful pyelolithotomy. It is concluded that the prevalence of infectious urinary calculi as a cause of uraemia in patients with ESRD is low. The time taken for uraemia to develop is short in these patients and they often have anatomical abnormalities. Proteus is commonly found in this group of patients. Patients with staghorn calculi, urinary tract infection and impairment of renal function are at risk of developing uraemia.

Aged↗

Branched renal calculi treated by percutaneous nephrolithotomy and extracorporeal shock waves.

Fifty-four renal staghorn calculi, 26 complete and 28 partial, were treated in 51 patients by percutaneous nephrolithotomy (PCN) in combination with extracorporeal shock wave lithotripsy (ESWL) when necessary. At an average time of observation of 11.1 months, 56% of the renal units were stone free. Twenty-two per cent had residual gravel of less than 2 mm in diameter and 15% contained residuals between 2 and 5 mm in diameter. Seven per cent of the kidneys had significant residual calculi. Additional endourological procedures were required in 13 cases. Complications were minimal and were all conservatively treated. PCN in combination with ESWL is an effective treatment of most branched renal calculi. The methods may be used repeatedly without increasing technical difficulty. The results compare well with open surgery.

Female↗

The management of urinary calculi in a stone centre.

We report the management of the first 100 patients who presented with upper urinary tract calculi to The Devonshire Hospital Lithotripter Centre. Ninety-two patients were treated by extra-corporeal shock-wave lithotripsy (ESWL) alone, four by percutaneous nephrolithotripsy (PCN) and two with staghorn calculi by combined ESWL and PCN. Ten patients had ureteric stones, and two of these required conventional open surgery. The average inpatient stay was 3.7 days. Half the patients required no analgesia after ESWL. Of the remainder, most were comfortable with oral analgesia. Almost all returned to normal activity within a few days of discharge. Complications were minimal and were managed by percutaneous or endoscopic techniques. These figures confirm the West German experience that ESWL is a safe and effective urological procedure and requires a skilled back-up of percutaneous and ureteroscopic skills for optimal patient management. By means of these techniques, conventional open surgery is necessary for the treatment of fewer than 5% of cases of calculi in the upper urinary tract.

Adolescent↗