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We compared quantitative urinary cystine values in stone-forming family members and unaffected relatives based on an index stone-forming patient. A family pedigree of 39 members was identified. Quantitative urinalyses and serum biochemical profiles were collected with the subjects on similar diets over 72 hours. Detailed medical histories were obtained. Three family members are stone-forming cystinuric patients with a mean urinary cystine excretion of 496 mg/g of creatinine per day. Six persons without a history of stones (mean age 50) had a mean urinary cystine excretion of 364 mg/g of creatinine per day. Thirty-four family members had elevated urinary cystine concentrations (mean 151 mg/g of creatinine per day), and only two family members had normal urinary cystine excretion. Fifteen subjects with elevated urinary cystine values (> 150 mg/g of creatinine per day) had no history of urinary stones despite a mean age of 44 years. Urinary electrolytes and volumes were similar in the stone-forming and non-stone-forming groups. Thirty-nine per cent of the persons from this family pedigree had elevated quantitative urinary cystine concentrations and no history of urinary stones despite a mean age of 44 years. Acalculous cystinuria is an elevated urinary cystine concentration without evidence of urinary stone disease. Despite abnormal urinary cystine excretion, acalculous cystinuria does not necessarily culminate in clinical urinary stone disease.

Urolithiasis is the third most common affliction of the urinary tract, after infections and diseases of the prostate. Approximately 10% of the North American population will have at least one urinary calculus by age 70. A thorough history and physical examination will usually confirm the diagnosis of urinary stone disease. A simplified laboratory evaluation may be performed for patients with a single stone episode. A more extensive evaluation is required for patients with recurrent, metabolically active stones and patients at high risk (ie, cystine stone formers and those who develop bladder dysfunction or nephrosclerosis). Intravenous pyelography with tomography remains the gold standard for imaging of the urinary tract to confirm the diagnosis and formulate a treatment plan.

Abnormalities in uric acid metabolism are associated with uric acid and calcium oxalate urolithiasis. Clinical stone formation depends on multiple identifiable risk factors that affect uric acid and calcium oxalate solubility. The understanding of urinary pH is critical to direct appropriate treatment of uric acid-related nephrolithiasis. Understanding uric acid metabolism and the pathophysiology of uric acid and calcium oxalate stone formation leads to a rational treatment approach to uric acid and hyperuricosuric calcium oxalate stone disease.

Purpose: We used high resolution radiography to identify and characterize Randall's plaques in cadaveric kidneys., Materials and Methods: A total of 50 consecutive sets of cadaveric kidneys was fixed, bivalved and imaged with micro-focal spot magnification radiography. Papillary calcifications were identified, localized and processed for light microscopy. Special immunohistochemical stains were implemented to aid localization of ectopic calcifications. Patient medical records and autopsy results were retrospectively evaluated and correlated with radiographic papillary calcifications., Results: Of the 92 renal units with complete data 52 (57%) had radiographic evidence of renal medullary calcifications consistent with Randall's plaques. Unlike the original description of this condition, calcifications extended deep into the papilla. A history of hypertension was the only clinical parameter correlating with papillary calcifications. Calcium deposition was localized to the basement membrane of collecting tubules and vasa recta, and papillary interstitium., Conclusions: Randall's plaques are not merely subepithelial deposits. Rather, they appear to extend deep within the papilla, and are intimately associated with collecting tubules and vasa recta. An association between papillary calcifications and urinary stone formation has yet to be proved but is under investigation.

Purpose: Pharmacological treatment of hypocitraturic calcium nephrolithiasis requires as many as 12 tablets, or numerous crystal packages or liquid supplements taken throughout the day. In addition to added cost, this cumbersome regimen decreases patient compliance, which may increase stone recurrence rates. We evaluated the urinary biochemical effects of dietary citrate supplementation in hypocitraturic calcium stone formers in an attempt to decrease or eliminate the need for pharmacological therapy., Materials and Methods: A total of 12 patients who were either noncompliant with or intolerant of pharmacological citrate therapy supplemented their routine diet with citrate in the form of lemonade, consisting of 4 ounces of reconstituted lemon juice (5.9 gm. citric acid) mixed with tap water to a total volume of 2 l. and consumed at uniform intervals throughout the day. Urine specimens (24-hour) were obtained for biochemical analysis after 6 days of lemonade therapy and compared to pre-lemonade baseline values., Results: Of the 12 patients 11 had increased urinary citrate levels during lemonade therapy (average 204 mg. per day). Average levels increased from 142 mg. daily (range less than 10 to 293) at baseline to 346 mg. daily (range 89 to 814) after treatment (p < 0.001). Daily total urinary volumes were similar (2.7 versus 2.9 l.). Seven of 12 patients became normocitraturic while consuming lemonade. Urinary calcium excretion decreased an average of 39 mg. daily, while oxalate excretion was unchanged. The lemonade mixture was well tolerated. Two patients complained of mild indigestion that did not require cessation of therapy., Conclusions: Citrate supplementation with lemonade increased urinary citrate levels more than 2-fold without changing total urinary volume. Lemon juice, which contains nearly 5 times the concentration of citric acid compared to orange juice, is an inexpensive and well tolerated dietary source of citrate. Lemonade therapy may improve patient compliance, and may be useful as adjunctive treatment for patients with hypocitraturic calcium nephrolithiasis.

Purpose: Endopyelotomy has been performed extensively in adults for the treatment of ureteropelvic junction obstruction. To determine its applicability to the pediatric population we reviewed our experience with retrograde endopyelotomy in children., Materials and Methods: Eight children 4 to 15 years old were treated with retrograde endopyelotomy and results were compared to those of a concurrent group of 8 treated with open pyeloureteroplasty., Results: Retrograde endopyelotomy was done in all of our patients with lower ureteral dilatation (as an adjunct measure in 5). Seven patients had symptomatic and radiographic improvement. The patient in whom the procedure failed had a crossing lower pole vessel. Postoperative analgesia, length of hospitalization and cost were lower in the endopyelotomy group., Conclusions: Retrograde endopyelotomy is feasible in children older than age 4 years and it results in reduced morbidity. The success rate is high but open surgery remains the standard, particularly when a crossing lower pole vessel is identified preoperatively.

The utility of indwelling double-J ureteral stents during extracorporeal shockwave lithotripsy (SWL) of renal calculi is ill defined. We evaluated 179 patients treated with SWL for small (< 20 mm in diameter) solitary renal calculi with (N = 27) or without (N = 152) indwelling ureteral stents. There was no significant difference in the stone-free rates at 1 month (both 52%) and 3 months (61% nonstented group v 67% stented group; P = 0.45) or in the retreatment rates (13.3% nonstented group v 14.8% stented group; P = 0.60). The incidence and severity of pain/renal colic were similar for the two treatment groups. There was minimal morbidity associated with SWL in either group. Placement of double-J stents for the purpose of improving stone-free rates, alleviating pain, or preventing ureteral obstruction in conjunction with SWL of solitary renal calculi < 20 mm in diameter is unnecessary.

Purpose: We evaluated the efficacy and safety of the Dornier compact lithotriptor for management of renal stones., Materials and Methods: We administered 191 treatments to 169 patients with renal stones on 176 occasions with the patient under combined parental sedation and analgesia. The Dornier Compact lithotriptor is mobile and ultrasound guided, and uses an electromagnetic energy source., Results: A total of 22 patients required a second treatment (13%), 123 (72.8%) were stone-free, 26 (15.4%) had fragments less than 4 mm. large, 16 (9.5%) had stone fragments larger than 4 mm, and 4 (2.4%) required auxiliary therapy (treatment failures). The side effects were mostly mild to moderate, with nausea and/or vomiting reported in 26 patients (14%), colic or pain in 66 (39%), ureteral obstruction in 2, steinstrasse in 7 (4%) and fever in 1. Our clinical results indicate that extracorporeal shock wave lithotripsy was effective for treatment of stones in the kidney, with a low incidence of complications and adverse effects. The lithotriptor used is much smaller, less expensive and user friendly with no installation requirements, rendering it mobile., Conclusions: The success rate with newer generation devices compares well with results obtained using other stationary and larger versions.

Purpose: Conflicting data on the role of diet in the pathogenesis of nephrolithiasis prompted us to review the relevant literature regarding the impact of diet on urinary stone disease., Materials and Methods: MEDLINE searches were obtained from 1966 to date using a variety of key words, including urolithiasis, nephrolithiasis, diet, protein, carbohydrate, fat, calcium, oxalate, phosphate, magnesium, sulfate, citrate, sodium, potassium, fiber, fluids, alcohol and vitamins. References earlier than 1966 were obtained through bibliographies of these MEDLINE searches. The search included in vitro and in vivo animal and human studies., Results: Of the extracted articles 83% addressed the issue of nephrolithiasis and diet, and were included in this report. All articles were independently reviewed by each of us. The reviews were summarized and compiled according to each dietary component., Conclusions: Appropriate dietary manipulation may be beneficial in the prevention of recurrent urolithiasis in only a select group of patients.

The dissolutive effects of sodium fluoride on human calcium stone particles were investigated in an in vitro model. Stone particles composed of 65% calcium oxalate and 35% calcium phosphate dissolved in a dose-dependent fashion with NaF exposure. Stone particles exposed to 60 mM NaF had a 17% reduction in particle mass after 24 hours and a 62% reduction after 7 days in comparison with experimental controls bathed in physiologic normal saline. The systemic toxicity of the dose of oral fluoride necessary to achieve the optimal tested urinary concentrations would likely preclude oral administration, but NaF may have an adjunctive role in upper urinary tract irrigation for residual stone fragments after lithotripsy or in chronic low-dose oral administration for prophylaxis against recurrent calcium nephrolithiasis.

Purpose: We studied the effect of second generation lithotripsy on renal function., Materials and Methods: We evaluated 42 patients with unilateral renal calculi by nuclear renography, serum creatinine levels, renal ultrasonography and plain radiographs., Results: There was no significant change in glomerular filtration rate at 1 or 3 months. Split function of the treated kidneys was lower at 1 month (mean 47.2%, p = 0.01) and 3 months (47.3%, p = 0.01) than before treatment (49.1%). A greater than 5% decrease in split function of the treated kidney occurred at 1 month in 6 patients (16.2%) and at 3 months in 3. Of the patients 23 (62.2%) were stone-free and 11 had residual fragments less than 4 mm., with a 19% retreatment rate for an overall success rate of 91.9%., Conclusions: Newer generation lithotriptors may limit renal damage while permitting satisfactory treatment of renal calculi.

Nephrostomy tubes occasionally are resistant to extraction. During the last 7 years 3 such patients with entrapped Malecot nephrostomy tubes have been treated successfully at our university. The entrapped nephrostomy tubes were removed by endoscopically incising an anchoring tissue bridge that had grown over a flange. A small endoscope was easily advanced through the lumen of the entrapped catheter to allow for adequate visualization and electrocautery of the anchoring tissue bridge. With this method an entrapped Malecot nephrostomy tube may be removed intact without significant injury to the renal parenchyma. Malecot nephrostomy tubes should be used with caution for long-term drainage of small intrarenal pelves.

Ureteroscopy (URS) and extracorporeal shockwave lithotripsy (SWL) battle for supremacy in the management distal ureteral calculi. In order to clarify issues surrounding this controversy, we created a decision tree modeling URS or SWL with literature-based probabilities and used as endpoints both cost and patient preferences. Ureteroscopy was more successful than single-session or multiple-session SWL, 92.1% v 74.3% or 84.5%, and had a lower retreatment/complication rate. Although initial SWL was only slightly more expensive than URS, $4,420 v $4,337, the difference increased when the additional costs of complications and retreatment were calculated, $6,745 v $5,555. Using values for an "average" patient, SWL was preferred to URS in terms of patient satisfaction. The most important factors distinguishing between URS and SWL were the success of treatment, the cost of initial therapy, and patient attitudes toward unplanned ancillary procedures and retreatment. Although no alteration of success rates and cost figures within reasonable ranges made URS less cost-effective than SWL, individual differences in patients' aversion for complications allowed URS to be preferred to SWL in some situations. Therefore, SWL is less cost-effective than URS and is not necessarily preferred by patients. The physician should be aware of the principal determinants of the choice between URS and SWL treatment of distal ureteral calculi.

We report a case of endocervicosis of the bladder. The tumor was successfully resected transurethrally. Histopathology of this rare condition is discussed and the literature is reviewed. The natural course of this entity is poorly documented and close followup is mandatory. When endocervicosis is differentiated confidently from adenocarcinoma, local treatment may be satisfactory.

Circumcision, the most common operation in male patients in the United States, is performed by a variety of health care professionals. Although not technically difficult, it results in a large number of reported and unreported complications annually. We report the successful reattachment of a distal penile glans, which was amputated when the Sheldon clamp was used for newborn circumcision. The literature is reviewed, and prevention and treatment of this type of circumcision injury are described.

In order to compare the effects of intraperitoneal and extraperitoneal insufflation of CO2, we obtained blood gas measurements and chest radiographs in dogs during insufflation into three sites: the peritoneal cavity alone, the retroperitoneal space with communication into the peritoneal cavity, and the retroperitoneal space alone. The blood pH fell a mean of 0.11 +/- 0.03 and the PaCO2 rose a mean of 16.0 +/- 3.7 mm Hg when insufflation included the peritoneal cavity, whereas when insufflation was limited to the retroperitoneum, the pH fell a mean of 0.05 +/- 0.03 and the PaCO2 rose a mean of 7.5 +/- 2.8 mm Hg. Extrapleural thoracic dissection of gas was noted in one animal after insufflation limited to the retroperitoneal space. These findings confirm that there is significant absorption of CO2 from the peritoneal cavity during laparoscopy with CO2 insufflation, whether the pneumoperitoneum is primary or occurs secondary to retroperitoneal insufflation. If the insufflated gas is limited to the retroperitoneal space, however, the absorption of CO2 appears to be reduced in this animal model. The risk of thoracic dissection of gas may be greater during extraperitoneal insufflation than during intraperitoneal insufflation.

To our knowledge we report the first case of pseudo-crossed renal ectopia without an apparent displacing retroperitoneal mass that was documented on sequential radiological studies. Ureteropelvic junction obstruction of the crossed kidney appeared to be the cause of pseudo-crossed renal ectopia. Our case is compared with previously described instances of pseudo-crossed renal ectopia and the pathophysiological basis of this condition is discussed.

Depending on size, duration of symptoms and their location in the collecting system urinary calculi may pass spontaneously in 16 to 93% of cases. The rate of infection and increase in size of stones in the renal pelvis or calix reaches 70% within months to years. Ureteral stones, however may lead to complications during a period of days to weeks. New minimally invasive treatment modalities have liberalized the indications for early intervention in cases of small stones.

A retrospective analysis of 100 consecutive ultrasonically guided percutaneous nephrostomy tubes placed under the guidance of urologists was done. Complications related to tube insertion included sepsis in 3% of the cases, renal pelvic perforations in 2% and hemorrhage in 1%. There were no deaths and no need for open surgical intervention to manage these complications. An additional 21% of the tubes malfunctioned more than 24 hours after insertion, including dislodgement in 11%, occlusion in 6%, hemorrhage in 1%, peritubular leakage in 1%, puncture site infection in 1% and severe incrustation in 1%. These delayed complications were independent of tube type. Nephrostomy tubes may be placed safely by urologists. Urologists usually direct the need for percutaneous nephrostomy tube placement and use these ports for endourological manipulations and, therefore, they should have a greater role in catheter insertion.

We analyzed retrospectively 127 percutaneous nephrolithotomies performed on 96 patients between 1986 and 1989 to estimate the average total blood loss from the procedure. Blood transfusions and a postoperative decrease in hemoglobin level were combined to estimate total blood loss. The average blood loss for uncomplicated 1-stage single puncture percutaneous nephrolithotomy was 2.8 gm./dl. hemoglobin. Factors potentially influencing blood loss were identified. Multiple punctures and/or renal pelvic perforation was associated with a 2-fold greater blood loss. Half of the expected blood loss occurred in patients with a preexisting nephrostomy tract. Calculus morphology, location, composition and length did not affect total blood loss, nor did the number of fragments or stone-containing calices. Other factors, such as puncture site, type of fascial dilation, hypertension, renal insufficiency, infection, previous open renal surgery or previous extracorporeal shock wave lithotripsy, also did not affect total estimated blood loss. During the study years the blood transfusion rate was 23% in all patients and 14% in those with a single puncture uncomplicated by renal pelvic perforation and without a mature nephrostomy tract. The only statistically significant risk factors influencing the likelihood of a blood transfusion were preoperative anemia and total blood loss. Although our current transfusion rate associated with percutaneous nephrolithotomy (4% in nonanemic patients from 1989 to 1992) is much lower, patients must be made aware of the likelihood of blood transfusion, and urologists should recognize the risk factors for blood loss and transfusion.

To evaluate compounds for the long-term inhibition of urinary calculi growth, we applied a newly developed in vitro assay to various metal-ligand complexes. The new experimental model--the preadsorbed calculi growth assay--was based upon the initiation of crystal growth in a metastable solution of calcium and oxalate with uniform granules derived from human renal calculi. Potential inhibitors were first absorbed onto the surface of the calculi granules, following which the loss of calcium from the seeded metastable solution was monitored as the indicator of calcium oxalate deposition. This assay allowed participation in the reaction by any matrix components present in the human calculi granules and limited the effect of the inhibitors to the calculi surface. Some complexes of metal ions with bisphosphonates had strong inhibitory effects, as opposed to citrate complexes which had minimal effect in this assay. Tin was the most potent metal ion, and pamidronate was the most potent bisphosphonate; together they slowed the growth of calculi granules to 9% of control. The inhibition by Tin-bisphosphonate complexes persisted despite a week of continual rinsing with a solution of sodium chloride and calcium. If the metal-bisphosphonate complexes are active in vivo as well, they might be considered for prophylaxis of calcium oxalate calculi or the prevention of regrowth of residual fragments following lithotripsy.

We present five patients with urinary matrix calculi, which, in contrast to the normally brittle calcigerous calculi, are soft, pliable, and amorphous. Common clinical features include a history of calcigerous stone disease, renal surgery, urinary obstruction or stasis, and chronic infection with Proteus species or coliforms. The diagnosis is usually made at surgery, but certain preoperative radiographic findings may be suggestive. Matrix calculi are radiolucent on plain abdominal films, although their appearance on nonenhanced CT scans is similar to that of calcigerous calculi despite their small mineral content. Extracorporeal shockwave lithotripsy is ineffective; open or percutaneous techniques are necessary. Histologic inspection reveals laminar concentric rings of organized matrix with an orderly, layered deposition of minerals. Histochemical investigation can provide insight into the possible sequence of events in normal calculogenesis. The successful management of urinary matrix calculi depends on a high index of suspicion and a thorough knowledge of their clinicopathologic features.

To our knowledge the prevalence of urinary stone disease and concurrent mild to moderate renal insufficiency has never been reported. A review of our last 2,000 urinary stone patients identified 33 (1.65%) with serum creatinine levels of 2.0 mg./dl. or greater at presentation. Chemical composition, location and complexity of the calculi, types of procedures required to render the patient stone-free and the effect of surgical intervention (independent of relief of obstruction) on renal function were evaluated. Mean serum creatinine level before surgical intervention and after placement of a ureteral stent or percutaneous nephrostomy tube in patients with evidence of obstruction was 3.2 mg./dl. (range 2.0 to 7.5). Complete or partial staghorn calculi were found in 21 of the 33 patients (64%), including 8 with bilateral staghorn calculi. Seven patients required 1 procedure, 1 required urinary alkalization alone and the other 25 required an average of 3.5 procedures each. Stone analysis revealed struvite, mixed calcium and uric acid to be the most common types. Followup creatinine values (the latest available within 1 year) and corresponding creatinine clearances showed remarkable improvement. The mean decrease in serum creatinine level was 1.2 mg./dl. (p < 0.001). There was no statistically significant difference in the rate of decrease between patients with pretreatment serum creatinine levels of 2.0 to 2.9 mg./dl. and those with initial values of 3.0 or more. Renal calculi and concurrent mild to moderate renal insufficiency warrant aggressive treatment. Patients demonstrate significant improvement in renal function independent of relief of obstruction.

Objectives: To determine the feasibility of retrograde endopyelotomy in the management of pediatric ureteropelvic junction (UPJ) obstruction., Methods: We treated 2 boys aged 4 and 6 years with the Acucise endopyelotomy device for symptomatic ureteropelvic junction obstruction. The Acucise device was placed over a Lunderquist guide wire with fluoroscopic guidance only and routine Double J catheters were left in situ for 6 weeks after the procedure. The morbidity of the treatment and the short-term outcome were assessed., Results: There were no acute complications and short-term follow-up results were satisfactory as determined by intravenous urography and diuretic renography., Conclusions: Ureteropelvic junction obstruction in children may be treated by retrograde endopyelotomy with the Acucise device. The principal potential advantage of this procedure is reduced morbidity. Our findings suggest that further evaluation is warranted.

Insomnia affects up to 40% of the general population yearly and is a significant cause of morbidity and mortality. The direct and indirect costs of insomnia place a tremendous economic burden on society and employers. In addition to the cost of medical treatment and drugs, measurable costs of insomnia include reduced productivity, increased absenteeism, accidents, and hospitalization, as well as medical costs due to increased morbidity and mortality, depression due to insomnia, and increased alcohol consumption. This article reviews the literature on the economic costs and effects associated with insomnia. Based on the data reviewed, a conservative estimate of the total annual cost of insomnia was calculated at $92.5 to $107.5 billion. Early recognition and treatment of insomnia can reduce the costs associated with the condition, as well as possibly prevent other illnesses.

Candiduria, due to Candida albicans, Candida glabrata and other organisms, has increased in frequency due the use of broad-spectrum antibacterials, immunosuppressive agents and other factors. The optimal management of candiduria is unknown due to an unclear definition of fungal urinary tract infection and the lack of well-designed clinical trials. Removal of urinary catheters, ruling out obstruction/stones and documenting presence of post-void residuals are useful in the management of candiduria. Amphotericin B bladder irrigants and oral fluconazole may be used in certain patients who are high risk or with persistence of candiduria after removal of the urinary catheter.

The search for alternatives to carbon dioxide (CO2) for insufflation during laparoscopy has included the consideration of helium. Helium is attractive because it is noncombustible and has no pharmacologic effects. Unfortunately, it is also relatively insoluble in blood, which potentially could exacerbate a venous gas embolism. We performed rapid intravenous injections of CO2 and helium into 4 dogs in amounts ranging from 5 to 10 ml of gas per kilogram body weight. Recovery after CO2 injection always occurred within 1 min. In 4 of 6 instances, the helium injection was fatal. Our results confirm that helium is more lethal than CO2 when injected intravenously. This implies that the use of helium for insufflation during laparoscopy might place patients at greater risk for adverse effects should venous gas embolism occur.

We report a new technique for the management of ureterovesical junction stenosis in a renal transplant recipient. Endoscopic retrograde resection of a bladder window permitted direct retroperitoneal vision and longitudinal incision of the distal ureter. Ureteral and bladder mucosa were in close proximity and were stabilized with a double-J catheter. This alternative transmural transvesical ureteroneocystostomy had minimal morbidity and may be an alternative to traditional open surgical repair of these lesions.

The genitourinary system is a common source of disease in many animal species as well as humans, and the practice of comparative endourology is possible because of advances in the past decade in minimally invasive human surgery. Zoo veterinarians may have limited formal urologic training, and increasingly limited public funding resources now leave most community zoos without specialized endourologic equipment or expertise. Urologists may offer or be called on to assist in the diagnosis and management of often rare and valuable species, providing services and expertise previously limited to humans. Such cases may provide intellectual and technical challenges beyond those seen in clinical practice, while applying the same basic universal urologic principles. We describe a cooperative approach to the management of animal urologic disorders based on a 5-year experience as consultants to the San Francisco Zoo and encourage an interdisciplinary approach between urologists and their local zoos where this may be useful in the preservation and maintenance of these valuable and important public resources.

We investigated the use of bisphosphonates, analogs of pyrophosphate that bind to mineralized tissue, to image renal calculi in vivo. Twenty stone-bearing kidneys in 15 patients without urinary obstruction were studied. 99mTechnetium-methylene diphosphonate was injected intravenously followed by 20 mg of furosemide 4 hours later, and images were obtained by gamma counter for 30 minutes. Areas of increased uptake corresponded with the sites of calculi, and even small or radiolucent calculi were easily seen. Counts in the region of each kidney, the L4 vertebral body, and a background area were combined to calculate a scintigram index (SI) for each kidney. The mean SI of the stone-bearing kidneys was 4.8 +/- 3.5 v 1.3 +/- 0.4 for the normal kidneys. There was correlation of the SI with stone composition and size but not with radiographic density. After correction for size, the SI of stone-bearing kidneys remained significantly higher than the SI of normal kidneys, but the differences between calculi of different compositions were diminished. Nonetheless, high SI values were associated with soft types of calculi and low values with hard types. Future investigations will reveal if this association is constant and if there is any relation between bisphosphonate uptake and response to lithotripsy. The sensitivity of urolithoscintigraphy to image small or radiolucent calculi may make it an effective technique for the assessment of residual fragments after lithotripsy.

Indications for laparoscopic pelvic lymphadenectomy prior to radical prostatectomy have not been established. Criteria to predict lymph node metastases were derived from the preoperative evaluations of 164 prostate cancer patients undergoing pelvic lymphadenectomy. Decision analysis was used to determine which criteria would be optimal indicators for laparoscopic pelvic lymphadenectomy prior to intended radical prostatectomy. Besides a digital rectal examination suggesting uncontained tumor, which was the best indication for laparoscopic pelvic lymphadenectomy, the most useful criteria were sonographic tumor volume > or = 3 cc and prostate-specific antigen (PSA) > or = 20 ng/mL. If either parameter was met, the sensitivity for identifying patients with pelvic lymph node metastases was 88 percent and the positive predictive value was 42 percent. When both were met, the sensitivity fell to 47 percent but the positive predictive value increased to 67 percent. A combination of Gleason biopsy score and PSA was the best criterion that was independent of transrectal ultrasonography. Using a PSA > or = 15 ng/mL for tumors with Gleason biopsy score > or = 7 or a PSA > or = 25 ng/mL for tumors with a Gleason biopsy score of 5-6 had a sensitivity of 71 percent and positive predictive value of 48 percent for identifying patients with pelvic lymph node metastases. In selecting patients for laparoscopic pelvic lymphadenectomy prior to radical retropubic prostatectomy, criteria with a positive predictive value greater than 39 percent maximize the utility of laparoscopic pelvic lymphadenectomy. Prior to radical perineal prostatectomy, laparoscopic pelvic lymphadenectomy will identify pelvic lymph node metastases that would otherwise be undetected by prostatectomy alone. The sensitivity of selection criteria, therefore, should be increased, as long as the positive predictive value remains above 20 percent.

An 8 cm. symptomatic simple renal cyst, recurrent despite previous aspiration and injection of sclerosing agents, was marsupialized using laparoscopic techniques. No complications occurred and followup by ultrasonography confirmed resolution of the lesion. We suggest that laparoscopic management of symptomatic simple renal cysts may be an attractive alternative to open surgical techniques.

Ureteral perforation with resultant retroperitoneal stone expulsion is a recognized complication of ureteroscopy. In a 5-year retrospective review of 400 cases we identified a 1.3% incidence of iatrogenic retroperitoneal stone dislodgment. Average followup was 21 months. Four cases were managed with observation and 1 required surgical correction of a ureteropelvic junction stricture. We discuss the management of this problem, which begins with thorough radiographic documentation in the perioperative period. Aggressive ureteroscopic manipulation and attempted stone retrieval are not warranted, and a ureteral stent should be placed. Radiographic followup and clinical observation confirm the low morbidity associated with retroperitoneal urinary stones. Patient understanding of the extra-ureteral stone location is essential to avoid misdiagnosis and mismanagement by uninformed physicians in the future.

Pyelocaliceal diverticula are cystic urine collections within the renal parenchyma communicating with the collecting system. They occur in 0.2% to 0.5% of the population and often contain calculi. Flank pain is the most common complaint, and most lesions are diagnosed by intravenous urography. In the past, treatment has required open renal surgery, with potential loss of renal function, or prolonged percutaneous procedures. We propose surgical treatment of caliceal diverticula by laparoscopic unroofing and fulguration. The benefits include renal preservation as well as decreased morbidity and an earlier return to work for the patient.

Suprapubic urinary diversion for the management of lesions of the bladder outlet or urethra has been facilitated by the advent of percutaneous access techniques. Prior to percutaneous endourologic techniques, an open surgical approach was necessary when the transurethral route was impassable. A variety of percutaneous suprapubic cystostomy techniques have evolved in recent years. These have been based on several different access principles and offer the urologist a number of options. Selection of an individual technique is usually a matter of preference and familiarity with a particular manufacturer's product. The list of indications for such an approach is diverse and continues to expand.

Six studies providing information on 2,704 patients were included into a retrospective analysis. The incidence of spontaneous passage relating both stone size and location was determined from these collated studies. The rate of spontaneous passage for stones smaller than 4 mm was 38% compared to 1.2% for those larger than 6 mm, irrespective of their position in the ureter at the time of presentation. Calculi discovered in the distal third of the ureter had a spontaneous passage rate of 45%, compared with the mid third of 22%, and the proximal third of 12%. Two thirds of all stones which passed did so within 4 weeks after the onset of symptoms. These data from the literature were compared to the treatment modalities applied for the last 100 consecutive patients treated with the diagnosis of ureteral stone at UCSF. 42% of the stones were found in the proximal, 13% in the mid and 45% in the distal third of the ureter. Treatment modalities included ureteroscopic stone extraction (36), ESWL (31) and watchful waiting for stone passage (30). Oral litholysis was performed in 2 cases and percutaneous removal of a proximal stone in 1. No calculus larger than 6 mm passed spontaneously. The passage rate from the proximal ureter was 18%, from the mid ureter 15%, and 38% from the distal ureter disregarding the size of the stones. The rate of complications reached 20% when symptoms exceeded 4 weeks in duration compared to 7% in patients with symptoms lasting less than 4 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)

Mechanisms for maintaining passive continence in the efferent limb of urinary diversions include compression of tissue, peristalsis, equilibration of pressure and use of valves. Motor activity and pressure in the ileum, ileocecal valve (ICV) and the colon were evaluated in dogs. Spontaneous activity and pressure were compared with stimulated pressure response and activity. Stimulation was performed at the pelvic nerve and the small nerves in the mesenterium, as well as direct neurostimulation of the bowel. Resting pressure at the ICV was 12.7 +/- 0.4 cmH2O rising to 26.4 +/- 2.2 cmH2O during spontaneous depolarization. Stimulation of the pelvic nerve resulted in increased colonic motor activity with unchanged pressure. Electric stimulation of small mesenterical nerves to the ICV increased pressure in the ICV to 35.0 +/- 4.1 cmH2O, while direct myoelectric stimulation of the ICV zone increased the intraluminal pressure to 75.0 +/- 3.2 cmH2O. Termination of the electric stimulation was followed by a slow decrease of pressure to the resting level over a period of 30-45 s. Maintaining continence at the ICV with long-term constant or intermittent stimulation seems feasible.

A series of 23 confirmed cases of pyonephrosis initially treated by percutaneous nephrostomy drainage were reviewed. Presentation was extremely variable, ranging from sepsis to asymptomatic bacteriuria. Fever, flank pain and leukocytosis were often absent. Ultrasonography was diagnostic in only 3 of 12 patients. In all, 17 patients had associated nephrolithiasis, and 5 patients ultimately required nephrectomy. Renal urine cultures were positive in 16 of 21 instances, with multiple organisms found in 8 of 21, and added bacteriological data not provided by bladder urine cultures in 11 cases. A pre-existing history of urinary tract infection, hypertension and malignancy was common. Percutaneous drainage was a safe, quick and effective diagnostic and therapeutic method.

Management of urinary stone disease in the morbidly obese patient can be troublesome and problematic. We present 4 recent female patients with an average weight of 442 pounds and an average height of 5 feet 2 inches. The patients underwent a total of 8 open surgical or endoscopic procedures for partial or complete staghorn calculi. Complications encountered included inability to reach the stones with rigid or flexible ureteroscopes, inadvertent incision above the 10th rib for pyelolithotomy, intraoperative rhabdomyolysis during a flank incision, consecutive temporary renal failure and wound infection. We discuss the limitations of extracorporeal shock wave lithotripsy, retrograde endoscopic manipulation, percutaneous antegrade surgery and open surgical approaches. Such patients continue to represent diagnostic challenges and high risk therapeutic options.

Although most ureters can now be stented, the rate of ureteral obstruction from extrinsic compression remains relatively high. To illuminate the mechanisms of obstruction in these patients we performed 20 in vivo pressure-flow investigations in 14 patients with indwelling ureteral Double-J stents. All patients had a percutaneous nephrostomy tube in place. Our investigations revealed proper drainage to the bladder in 17 of the 20 studies at an average renal pelvic pressure of 19.9 cm. water. Vesicorenal reflux was noted at an average bladder pressure of 20 cm. water in 17 studies. Three stents appeared to be obstructed. They showed no drainage to the bladder but also no reflux. To evaluate the in vivo results we then performed an in vitro study of pressure-flow characteristics under conditions simulating ureteral obstruction. At physiological flow rates different ureteral stents showed no major differences in pressure-flow characteristics. With compression and kinking, flow resistance in softer stents was notably greater than in hard stents. Therefore, we believe that in patients with suspected extrinsic compression of the ureter hard Double-J stents should be used. Vesicorenal reflux appears to be a reliable predictor of stent function.

A retrospective analysis of 156 rigid ureteroscopic stone procedures in 145 patients revealed successful manipulation in 90%. The stone-free rate after adjunctive procedures was 95%. Access was achieved without balloon dilation in all but 18 patients. There were 24 perforations, occurring in 31% of proximal, 8% of mid ureteral and 8% of distal stone manipulations. Of the evaluable patients 63% underwent radiographic assessment for stricture disease, 75% at 6 months or more after the procedure. The stricture rate was 3.5% in all patients and 5.9% in patients with perforations. Of 37 patients evaluated for vesicoureteral reflux only 1 had reflux. Questionnaire followup was obtained for 74% of the patients (mean followup 2.6 years) and 32% felt normal within 3 days. Postoperative symptoms included flank pain (13%), renal colic (12%), pelvic discomfort (30%) and Double-J stent related complaints (49%). Of the patients 15% have reported recurrent stones. Ureteroscopy is effective and well tolerated, and it has minimal long-term complications.

Renal artery embolism is an infrequent but important cause of renal loss. However, due to its rarity and nonspecific presentation diagnosis is often delayed and occasionally missed. Furthermore, proper therapeutic intervention is not well established and aggressive surgical management is often ill-advised. We review the literature and present 3 cases seen recently at our institution. Selective intra-arterial infusion of thrombolytic agents appears to be the most favorable treatment. The duration of occlusion does not necessarily correlate with the return of renal function, and the degree of collateral renal blood flow can be important.