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W L Strohmaier

Publications and source records attributed to W L Strohmaier.

At least 19 recordsLinked to original sources

[Economic aspects of evidence-based metaphylaxis].

The calculation model which we developed for the cost of stone therapy and metaphylaxis in Germany some years ago with a social health insurance company is based on estimates of stone incidence, types and recurrence rates, actual costs for stone removal, and metaphylaxis (based on data from a district of the social health care system). There are 200,000 stone recurrences per year in Germany. Costs for treatment of these stones amount to $687,000,000. Stone metaphylaxis reduces the recurrence rate by some 40%. The annual cost for stone removal could be lowered by $275,300,000. Metabolic evaluation/metaphylaxis amount to $70,100,000 per year, resulting in a net saving of $205,200,000. In 1997, there were 96 days off work per stone patient resulting in 5,800,000 days off work in Germany per year. Metaphylaxis is not only medically effective in stone formers but also can lower health care cost significantly. Although health care conditions may vary from country to country, in principle this calculation model is applicable also to other countries.

Cost-Benefit Analysis↗

Diagnosis and metaphylaxis of stone disease. Consensus concept of the National Working Committee on Stone Disease for the upcoming German Urolithiasis Guideline.

This review draws the recent state of the art in metabolic diagnosis and metaphylaxis of stone disease. It is the basis for the consensus approval with the other medical societies and institutions in Germany involved in the guideline process of the new "Urolithiasis Guideline". The German Working Committee on Stone Disease reviewed critically the current literature in the field of urolithiasis-including the existing German and EAU-Guidelines as well as the Conference Book of the First International Consultation on Stone Disease. As far as possible the references were rated according to the EBM criteria. On this basis the expert group discussed all pathways and statements regarding the management of stone disease. The present review coincides with the consented guideline draft of the German Working Committee on Stone Disease. Occurrence of stone disease in the western world increases seriously. Modern lifestyle, dietary habits and overweight-problems of the affluent societies-emerge to be the important promoters of the "stone-boom" in the new millennium. This even affects children, whose stone prevalence is otherwise significantly less than that of adults. Criteria for the high risk group of stone formers were clearly defined. A diagnostic standard is formulated for the basic and the elaborate metabolic evaluation of a stone patient. Approximately 75% of all stone patients could anticipate stone recurrence with elementary reorientation of their lifestyle and dietary habits, summarized as general metaphylaxis. About 25% of the stone formers require additional pharmacological intervention to normalize their individual biochemical risk, precisely compiled for each stone type as specific metaphylaxis.

Consensus↗

Renal tubular alteration by crystalluria in stone disease-an experimental study by means of MDCK cells.

OBJECTIVES: Physicochemical properties of urine do not explain the formation of urinary stones. Clinical findings and results of animal experiments suggest that alteration to the renal tubular cell plays a key role in the initiation of urinary stone formation. It is not clear whether this is a primarily intracellular alteration of metabolic origin which, after lysis of the renal tubular cell in the lumen, presents a nucleus for the formation of concretions, or whether in the lumen it is tubular cell damage induced by crystalluria that triggers the formation of urinary stones. MATERIALS AND METHOD: Using Madin-Darby canine kidney cells, the influence of crystalluria on the renal tubular cell was tested in cell cultures. The influence of parathyroid hormone, vitamin D(3), oxalate and calcium concentrations and the extent to which these processes can be inhibited by allopurinol and selenium were investigated. RESULTS: Calcium oxalate monohydrate crystals produced reproducible damage to the renal tubular cell which was independent of parathyroid hormone and vitamin D(3). The crystalluria-induced effects were unrelated to the oxalate and calcium concentration or the pH. Allopurinol and selenium were able to inhibit the processes. CONCLUSION: The results indicate secondary involvement of the renal tubular cell in lithogenesis as a result of luminal alteration caused by calcium oxalate crystals. Mechanical damage and interaction between crystal and tubular cell lead to the apposition of crystals. The nephroprotective effect of allopurinol and selenium as antioxidants might explain the benefit of allopurinol found clinically in terms of stone metaphylaxis.

Animals↗

[Treatment of a subcapsular renal bleeding after extracorporeal shockwave lithotripsy with recombinant, activated factor VII].

We report on a patient who suffered a large subcapsular and perirenal haematoma after extracorporeal shockwave lithotripsy. Despite surgical intervention the bleeding did not stop for 6 days and 10 units of packed red blood cells were transfused. With the treatment of recombinant, activated factor VIII (NovoSeven((R))) an immediate haemostasis could be reached, so that impending nephrectomy could be avoided. This is the first case where FVIIa has been successfully used to stop a trauma-related bleeding in a patient without any obvious accompanying coagulation disorder.

Blood Transfusion↗

Minimally invasive PCNL in patients with renal pelvic and calyceal stones.

Stones of the renal pelvis can be treated either by extracorporeal shock wave lithotripsy (SWL) or percutaneous nephrolithotomy (PCNL). As a low-risk procedure with a longer treatment period, SWL often leads to persistent residual stone fragments, whereas conventional PCNL achieves a higher stone-free rate and allows a shorter treatment period albeit with a somewhat higher surgical risk. To reduce the invasiveness of conventional PCNL, the application of a miniaturised instrument for PCNL (MPCNL) was evaluated. For MPCNL a rigid nephroscope with a calibre of 12 F was developed and used in 19 patients. After puncture of the kidney under ultrasound control and single-step dilatation, a 15 F Amplatz sheath was placed. Data on the stone size and location, stone-free rate, blood transfusions, operating time and complications were recorded. In all patients, the part of the kidney afflicted by the stone was successfully punctured. On average, retreatment rate was 0.7. The mean stone size was 2.4 cm(2). The average operating time was 99.2 min. In every case, the absence of residual stones was confirmed radiologically and nephroscopically. Hemorrhages requiring a blood transfusion did not occur. A febrile pyelonephritis occurred as a postoperative complication in one patient (= 5.3%). MPCNL represents an alternative to SWL for renal calculi with a size from 1 to 2 cm located in the renal pelvis and calices, especially the lower calix. The advantages are the short treatment time, the high stone-free rate and the accessibility of lower pole stones which are less amenable to SWL. MPCNL is not suitable for large concrements since the limited sheath diameter would increase the operating time. Due to this limitation, MPCNL represents an extension of the indication for conventional PCNL that it can in no way replace.

Humans↗

Porcine urinary tract as a training model for ureteroscopy.

OBJECTIVES: Endourological procedures as ureteroscopy require an advanced level of skills. To facilitate the training of the proper technique, simulators are helpful. Nonbiological models, useful to learn the basic steps, do not represent the clinical situation in an ideal way. We therefore looked for a biological but nevertheless easily available model. METHODS: The complete urinary tract is dissected off the retroperitoneal organ package of freshly slaughtered pigs. RESULTS: The porcine urinary tract model allows for training all aspects of diagnostic and therapeutic ureteroscopy including lithotripsy and stenting in a way which is almost identical to the clinical situation in humans. CONCLUSIONS: The porcine urinary tract model is an ideal ex vivo model. Concerning 'tissue feeling' and anatomic relations, it is superior to nonbiological simulators. Nevertheless, it is quite easily available and inexpensive. In training courses, we have used it with great success.

Animals↗

[Socioeconomic aspects of urinary calculi and metaphylaxis of urinary calculi].

A calculation model was developed for the cost of stone therapy and metaphylaxis in Germany based on estimates of stone incidence, types and recurrence rates, actual costs for stone removal and metaphylaxis (based on data from a district of the social health care system). There are 200,000 stone recurrences per year in Germany. Cost for treatment of these stones amount to $687,000,000. Stone metaphylaxis reduces the recurrence rate by some 40%. The annual cost for stone removal could be lowered by $275,300,000. Metabolic evaluation/metaphylaxis amount to $70,100,000 per year, resulting in an net saving of $205,200,000. In 1997, there were 96 days off-work per stone patient resulting in 5,800,000 days off-work in Germany per year. Metaphylaxis in stone formers can lower health care cost significantly. Although health care conditions may vary from country to country, in principle this calculation model is applicable also to other countries.

Adult↗

Arterial blood pressure following different types of urinary stone therapy. Presented at the 8th European Symposium on Urolithiasis, Parma, Italy, 1999.

OBJECTIVE: Several studies reported increased blood pressure (BP) values following extracorporeal shock wave lithotripsy (ESWL) treatment of renal stones. It is unclear, however, whether this is due to ESWL, since nephrolithiasis itself increases the relative risk of developing hypertension. Therefore we prospectively studied the BPs of stone patients undergoing different types of treatment. METHODS: 252 stone patients (63% males, 37% females, median age 44.3, range 11.7-86.4 years) participated. 168 suffered from uretral stones: 50 underwent ESWL; 40 ureteroscopy, and 78 patients passed stones spontaneously (SP). 84 had renal stones: 60 underwent ESWL; 8 percutaneous nephrolithotomy/open surgery, and 16 no treatment. Systolic (SBP) and diastolic (DBP) BP were measured according to Riva-Rocci prior to, immediately after, and 3, 6, 12, 18 and 24 months after stone therapy. RESULTS: Immediately after SP, SBP decreases, whereas after active stone treatment increases (highest after ESWL) in SBP were seen. DBP was unchanged. During the further follow-up, a gradual increase in BP was observed in all groups. At 24 months in all groups, regardless of the stone location and type of treatment, SBP and DBP were significantly higher than the pretreatment levels (p = 0.000). There was no a difference between renal and ureteral stones, or between the ESWL treatment and the other groups. CONCLUSION: Renal stone disease itself rather than the type of treatment significantly increases SBP and DBP during a follow-up period of 24 months. The underlying mechanisms remain to be elucidated.

Adult↗

Course of calcium stone disease without treatment. What can we expect?

OBJECTIVES: The knowledge of the natural history (i.e. the course of the disease without metaphylaxis is the base for establishing rational guidelines for metaphylaxis in urolithiasis. METHODS: This review is based on a Medlinetrade mark Search (1966-1999) and the proceedings of the Bonn-Vienna and European symposia on urolithiasis. Only 31 references were sufficient for the purpose of this review. RESULTS: In idiopathic calcium stone disease, stone frequency without metaphylaxis is 0.10-0.15 stones per patient per year. The average recurrence rate is 30-40%. Recurrence rate increases with age and observation time. Risk for recurrence is highest during the first 4 years after the first stone episode. More than 50% of all recurrent stone formers have only one recurrence during their lives. 10% of recurrent stone formers have more than 3 recurrences. Risk factors for recurrence are: male sex, multiple and lower calyx stones, early onset, familial history, complications after stone removal. Metabolic evaluation is a poor predictor of the risk for recurrence. CONCLUSIONS: Renunciation of metaphylaxis is justified in first stone formers with idiopathic calcium oxalate and apatite stones. All patients, however, should be advised to increase their fluid intake.

Adult↗

Comparison of symptoms, morphological, microbiological and urodynamic findings in patients with chronic prostatitis/pelvic pain syndrome. Is it possible to differentiate separate categories?

164 patients with prostatitic symptoms were evaluated by segmented urinalysis and culture and classified according to the National Institutes of Health classification system: 64 patients (38%) suffered from chronic bacterial prostatitis; 12 (7%) from inflammatory chronic pelvic pain syndrome, and 92 (55%) from non-inflammatory chronic pelvic pain syndrome. Transrectal ultrasound of the prostate, uroflowmetry and measurement of residual urine were also performed. Complaints were recorded using a questionnaire. Our studies revealed that leukocytes in expressed prostatic secretions could be detected in only 24 and 36% of patients with positive bacterial or chlamydial culture. Complaints, ultrasound and urodynamic findings were similar in the 3 groups. Therefore the differential diagnosis and therapy, based on the results of the 4-glass test and cultures as well as on transrectal ultrasound of the prostate, seem to be difficult.

Chronic Disease↗

Reduction of high-energy shock-wave-induced renal tubular injury by selenium.

In shock-wave-induced renal injury cavitation-generated free radicals play an important role. Using an in vitro model with Madin-Darby canine kidney (MDCK) cells, we investigated the influence of selenium, a free radical scavenger, in shock-wave-induced tubular cell injury. Suspensions of MDCK cells (33 x 10(6) cells/ml) were placed in small containers (volume 1.1 ml) for shock wave exposure. Two groups of 12 containers each were examined: (1) control (no medication), (2) selenium (0.4 microg/ml nutrient medium). Six containers in each group were exposed to shock waves (impulse rate 256, frequency 60 Hz, generator voltage 18 kV), while the other six containers in each group served as a control. After shock wave exposure, the concentration of cellular enzymes such as lactate dehydrogenase (LDH), N-acetyl-beta-glucosaminidase (NAG), glutamate oxaloacetate transaminase (GOT) and glutamate lactate dehydrogenase (GLDH) in the nutrient medium was examined. Following shock wave exposure there was a significant rise in LDH, NAG, GOT and GLDH concentrations. Selenium reduced this enzyme leakage significantly. Thus we conclude that selenium protects renal tubular cells against shock-wave-induced injury. Since selenium is an essential part of glutathione peroxidase, this effect seems to be mediated by a reduction in reactive oxygen species.

Animals↗

Follow-up in prostate cancer patients: which parameters are necessary?

AIM: In a retrospective study we examined whether follow-up of prostate cancer (PC) patients can be managed by using prostate-specific antigen (PSA) as a unique tool as postulated recently. PATIENTS AND METHODS: According to strict criteria established in the eighties, at our institution PC patients were monitored by PSA, prostatic acid phosphatase (PAP), alkaline phosphatase (AP), digital-rectal examination, renal and bladder ultrasound every 3 months, abdominopelvic computerized tomography (CT) and bone scan every 6 months. Between 1988 and 1994, 80 patients with PC cancer were eligible (mean follow-up 29.5, range 12-81 months). Patients were categorized into 4 groups: localized tumor (n = 44); lymph node metastases (n = 9); distant metastases (n = 18), and lymph node and distant metastases (n = 9). The parameters mentioned were compared for the assessment of progression, regression and stabilization of the disease. RESULTS: Our examinations showed that PSA is superior to all the other parameters used. In all groups, there were no patients with progressive disease detected by PAP, AP, CT and bone scan, but not by PSA. PSA anticipated the other parameters in detecting progression by several months. Renal ultrasound, however, detected new hydronephrosis in 6 patients with stable or decreasing PSA. Hydronephrosis was caused by surgery or radiotherapy, not by progressive PC. CONCLUSION: PSA can be used as a unique tool in the follow-up of PC patients in all stages. However, patients who underwent therapy potentially afflicting the urinary tract should have additional renal and bladder ultrasound.

Acid Phosphatase↗

Comparison of extracorporeal shock wave lithotripsy and ureteroscopy in the treatment of ureteral calculi: a prospective study.

146 patients whose ureteral stones did not pass spontaneously participated in a prospective study on optimal management. Patients were offered two treatment options: extracorporeal shock wave lithotripsy (ESWL) and ureteroscopy (URS). The stone was treated with the technique preferred by the patient. In case of treatment failure after first-line therapy, patients again could decide on how to proceed. Stone analysis could be obtained from 72.6% patients. ESWL was the primary treatment in 66.4% patients. In 2 patients, ESWL was the secondary treatment after failed URS. URS was the first-line therapy in 33.6% patients. In 29 patients URS was done after failed ESWL. For analgesia, sedoanalgesia or spinal anesthesia were used. Analgesia was required in 74.2% ESWL and 100% URS sessions. Following ESWL, 70.1% patients became stone free. In 29.9% ESWL failed. Distal stones had a higher failure rate than proximal or mid-ureteral calculi. Distal stones treated without success were significantly larger than those treated successfully. Failures were switched to URS. Stone analysis could be obtained in 26 patients with failed ESWL: 23/26 consisted of pure whewellite or mixed whewellite stones. Clinically relevant complications were not observed. After URS, 94.9% of the patients became stone free. In distal stones, the stone-free rate was 97.5%. There was only 1 relevant complication: a proximal ureteral lesion requiring surgical repair. Our study demonstrates that URS is a safe and highly effective treatment option for ureteral stones. In patients with distal ureteral stones, it should be offered as a first-line treatment. When whewellite is expected as the stone mineral, URS is the treatment of choice.

Adolescent↗

Excretion of tamm-horsfall protein in patients with uric acid stones.

The cause of reduced Tamm-Horsfall protein excretion in patients suffering from uric acid diathesis is still unknown. Our investigation was conducted based on the hypothesis that the solubility of uric acid is increased by Tamm-Horsfall protein and that an increased uric acid content in the urine might cause a decrease in Tamm-Horsfall protein. In 20 patients with uric calculi the excretion of Tamm-Horsfall protein, uric acid, calcium, and citrate was measured. 65% of the patients had pure uric acid stones (group I) and 35% showed mixed stones with at least 30% of uric acid (group II). Reduced Tamm-Horsfall protein excretion was found in 63% of the patients of group I and in 43% of the patients of group II. The excretion of Tamm-Horsfall protein was significantly reduced in pure uric acid stone formers compared to normal subjects (p < 0. 0001). The excretion of uric acid was elevated in 61% of the patients of group I and in 86% of the patients of group II. There was no significant correlation between Tamm-Horsfall protein excretion and uric acid excretion (r = 0.2139). Calcium excretion was elevated in 57% of the patients with mixed stones. The excretion of citrate was reduced in almost all of the patients of groups I and II. Our results do not support the hypothesis that an increased content of uric acid in the urine causes a decrease in Tamm-Horsfall protein. In our opinion the lower excretion of Tamm-Horsfall protein in some of the stone patients might be caused by damage in the distal tubular epithelium. Moreover, it has to be supposed that there are defects both in the distal and the proximal tubule in patients prone to develop uric acid calculi.

Albuminuria↗

Indications for open stone removal of urinary calculi.

In a retrospective study we analyzed patients undergoing open stone removal in the Department of Urology of the University of Tübingen. In 2.7% of all urinary calculi, open stone surgery was necessary. Open operation was performed on all patients with complete staghorn calculi as well as on patients with renal pelvic stones and simultaneous morphological obstruction. Partial staghorn calculi were operated on only after endoscopic treatment had failed. Small renal pelvic stones and ureteral stones were surgically removed only after extracorporeal shock wave lithotripsy (ESWL) and endoscopic surgery had been unsuccessful. The treatment of choice for ureteral calculi is ESWL. If ESWL is impossible, an endoscopic approach is advisable. Open operations of ureteral calculi only have to be performed if endoscopic therapy has failed or if there is a simultaneous morphological obstruction. Meta-analysis of publications from 1981 to 1995 confirmed our approach regarding indications for open stone removal. Comparison of the results reported in the literature is very difficult because of the missing, but generally accepted definition of stone free. In addition different examination techniques to determine the status 'stone free' make it difficult to compare the various studies.

Endoscopy↗

Spot urine samples for the metabolic evaluation of urolithiasis patients.

OBJECTIVES: This prospective study was initiated to assess the significance of spot urine specimens (SU) for the metabolic evaluation of stone formers. METHODS: 68 stone patients (51 males, 17 females) and 20 controls (9 males, 11 females) participated. On 3 consecutive days, urine was collected. Fasting (SU1) and postprandial (SU2) SU were obtained. From these, aliquots were taken, all the other urine was mixed to obtain 24-hour timed specimens (24hU). In all specimens, pH, specific gravity, creatinine, calcium, magnesium, phosphate, citrate, uric and oxalic acids were measured. The latter analytes were related to creatinine (mmol/g creatinine). Pearson correlation coefficients with their levels of significance and the day-to-day variation were calculated. Using the values in the control group, normal values (means +/- 2 SD) were established. RESULTS: There was a significant correlation (p < 0.0001) between SU and 24hU for all parameters examined. The day-to-day variation of all analytes was considerable in SU and 24hU. CONCLUSIONS: Despite a minor inaccuracy by relating parameters to creatinine, SU are sufficient in the routine metabolic evaluation of stone formers, since a third of all 24hU has to be rejected because of considerable collection errors. SU circumvent this problem. Because of the day-to-day variation, 3 SU should be obtained to overcome the doubtful significance of one single specimen.

Adolescent↗

[Studies of calcium metabolism in patients with hypercalciuria].

The different subgroups of hypercalciuria cannot be separated clearly by the Pak calcium-load test. To improve the diagnosis and therapy we examined all relevant parameters of calcium metabolism in 32 patients with calcium urolithiasis and hypercalciuria (> 6.25 mmol/day). We also conducted bone mineral density measurements as well as the Pak calcium-load test. In most cases the pathophysiological constellations which Pak takes as the basis for his classification of hypercalciuria could not be shown. To date, diagnostics only insufficiently explains the genesis of hypercalciuria (except pHPT). As a consequence, a therapeutic problem arises: a low-calcium diet should not be generally recommended, since some patients may develop osteopenia. From our investigation the following diagnostic and therapeutic conclusions can be drawn: (1) Hypercalciuria in primary hyperparathyroidism should be treated by surgical removal of the adenoma. (2) The parathormone-independent osteogenic form should be treated with thiazides. (3) Hypercalciuria with increased 1.25-dihydroxyvitamin D should be treated by low-calcium diet.

Adult↗

Osteocalcin response to calcium-restricted diet: a helpful tool for the workup of hypercalciuria.

OBJECTIVES: The treatment of hypercalciuria is controversial. This study investigated whether the osteocalcin response (OCR) to a calcium-restricted diet is a potential tool for the differential therapy of hypercalciuria. 56 patients with calcium urolithiasis were investigated. METHODS: Osteocalcin (OC) was measured on a free diet (OC 1) and after a calcium-restricted diet (400 mg/24 h for 1 week, OC 2). The OCR was expressed as 100 x (OC 2 - OC 1)/OC 1. A calcium load test and vertebral mineral density measurements (L2-L4) were performed additionally. RESULTS: 27 patients showed diet-dependent hypercalciuria, 15 of them being classified as absorptive hypercalciuria type II (AH II). 12 were normocalciuric (NC). 29 patients had diet-independent hypercalciuria, 22 being classified as renal hypercalciuria (RH), 7 as absorptive hypercalciuria type I (AH I). 22 patients (42%) showed a positive OCR, indicating an increased bone turnover. Vertebral mineral density was lower in patients with positive than with negative OCR. Generally patients with RH or NC showed a positive OCR, patients with AH a negative or no OCR. 2 patients with AH, however, showed highly positive OCR, indicating negative calcium balance. Long-term follow-up on a low calcium diet showed a steady decrease in bone mineral density. CONCLUSIONS: This demonstrates that the OCR is more reliable to determine the appropriate management of hypercalciuria than calcium load tests. For practical purposes, we suggest treating hypercalciuric patients with positive OCR with thiazides; diet-dependent hypercalciuria with negative OCR should be treated with a low calcium diet.

Absorptiometry, Photon↗