Is the conservative management of ureteric calculi of > 4 mm safe?

OBJECTIVE: To determine the safety of the conservative management of ureteric calculi of > 4 mm in diameter, using mercapto-acetyltriglycine (MAG3) radioisotope renography to monitor renal parenchymal function. PATIENTS AND METHODS: Patients with symptomatic unilateral ureteric calculi were recruited prospectively. After confirming the position of the stone using contrast urography, a MAG3 radioisotope renogram was taken within 48 h of admission and again 1 month after the patients became stone-free. The indications for intervention were ipsilateral loss of function (>/= 5% loss), infection, pain or any combination of these factors. The recovery of function was determined by follow-up renography. RESULTS: In all, 54 patients were recruited; 18 were initially allocated to conservative treatment although four later required intervention for pain. The remainder required early intervention for pain (eight), diminished function only (15) or diminished function with infection (13). Of the 54 patients, 28% had 'silent' loss of renal function at presentation. No calculi of > 7 mm diameter passed without intervention. The mode of initial management was determined according to individual clinical need. The upper tracts of all patients were relieved of obstruction and all patients were rendered stone-free. Intervention for reduced function only (at 相似文献   

Intrapelvic pressure and caliceal dilatation in the evaluation of intermittent hydronephrosis

We investigated 10 patients with suspected unilateral hydronephrosis and normal or minimal widening of the calices or renal pelvis on routine urography by high rate perfusion of the renal pelvis and simultaneous intrapelvic pressure measurement. All affected kidneys had reduced renal function (26 +/- 7 ml. per minute per 1.73 body surface area) evaluated from total and separate glomerular filtration rate studies using 51chromium-ethylenediaminetetraacetic acid clearance technique and isotope renography. Four patients without signs of obstruction operated upon because of renal calculi were used as controls with separate glomerular filtration rates greater than 40 ml. per minute per 1.73 body surface area bilaterally. The drainage function of the renal pelvis was studied by diuresis renography, simultaneous intrapelvic pressure measurement and fluoroscopy during infusion of roentgen contrast medium at a constant rate of 10.5 ml. per minute. The caliceal dilatation was calculated from planimetrical measurement of defined calices. The intrapelvic pressure gradually increased in all kidneys to a maximum value varying from 25 to 81 cm. water (average 47 +/- 15). In the control kidneys the intrapelvic pressure varied from 10 to 18 cm. water (average 14 +/- 3). Significant dilatation of the caliceal system did not occur until intrapelvic pressure values above 25 cm. water were measured. Caliceal dilatation and maximal intrapelvic pressure were correlated significantly to each other at a correlation coefficient of 0.95. Intrapelvic pressure flow measurement with contrast medium and roentgen film exposure at the time of increased pressure proved to be a useful method to diagnose outflow obstruction. The test was of particular value in cases of clinically suspected intermittent hydronephrosis, giving more reliable information than conventional renography and diuretic urography. The test could be used even when the glomerular filtration rate was decreased, thereby providing information on the presence of obstruction in cases when conventional renography and diuresis urography sometimes fail.     

Functional characteristics of idiopathic hydronephrosis

The functional characteristics of idiopathic hydronephrosis were studied in 171 patients. Conventional renography and measurement of the glomerular filtration rate were performed in all subjects, 137 (79%) of whom had normal parenchymal function despite severely reduced drainage function. Proximal tubular function, measured by determination of beta 2-microglobulin excretion was not reduced. Distal tubular function, evaluated as the maximum concentration ability, was not reduced in 35 of the 89 patients studied. During urography and diuresis renography were both useful tools for verifying the presence of obstruction in doubtful cases. Intrapelvic pressure was measured during constant perfusion at a rate of 7.5 ml/min and during furosemide-induced diuresis. The basal intrapelvic pressure varied from 6 to 10 cm H2O and was not increased in any kidney regardless of the degree of duration of obstruction. During perfusion, the pressure increased and varied from 28 to 52 cm H2O. During diuresis, an increase in pressure above 20 cm H2O was registered only in obstructed kidneys with a normal urinary concentrating ability. The pressure rise never exceeded 20 cm H2O during diuresis in obstructed kidneys with complications such as calculi of previous episodes of upper urinary tract infection. From these studies it is concluded that, besides cases with complications such as urinary tract infection and renal calculi, surgery should be offered to patients with idiopathic hydronephrosis with reduced urinary concentrating ability. In doubtful cases with wide pelves, renography and urography during increased diuresis can be used provided kidney function is not reduced. When kidney function is reduced, a pressure increase above 20 cm H2O during constant perfusion at a rate of 7.5 ml/min indicates obstruction.     

Evaluation of hydronephrosis in pregnancy using ultrasound and renography

The value of ultrasound and 131-Hippuran renography for diagnosing hydronephrosis during pregnancy was investigated. In a control series of 31 symptom-free pregnant women the ultrasonographically measured renal pelvic diameters in the three trimesters were 5, 10 and 12 mm on the right side and 3, 4 and 5 on the left, respectively. In ten healthy non-pregnant women the pelvic diameter varied from 3 to 9 mm on the right side and from 2 to 6 mm on the left side when measured during antidiuresis and water diuresis. Out of 35 pregnant women complaining of flank pain, 31 showed an increased renal pelvic diameter. These 35 women also underwent renography on the same day as the ultrasound examination. In 6 of 27 pregnant women with right-sided pain and in 3 of 8 with left-sided pain, diuresis renography indicated acute ureteral obstruction and in 6 of these 9 patients impairment of renal parenchymal function was also evident. In some cases the impaired renal function was fully reversed after surgical intervention. It is concluded that ultrasound investigation of the kidney is a valuable method for screening prior to renography. Since the negative prediction value of using 17 mm as the upper limit of the pelvic diameter was 100%, patients with a smaller pelvic diameter may not need to be referred further for renography or urography, and radiation will thus be minimized. On the other hand, renography is indicated when the pelvic diameter is more than 17 mm in patients complaining of flank pain.(ABSTRACT TRUNCATED AT 250 WORDS)     

Shock wave lithotripsy in solitary functioning kidneys: is prophylactic stenting necessary?

OBJECTIVE: To assess the safety of shock wave lithotripsy (SWL) without prophylactic stents in solitary functioning kidneys. PATIENTS AND METHODS: Sixteen solitary functioning kidneys with 23 renal stones with a size of <15 mm were treated with SWL as the primary modality. All patients were counseled about the possibility of obstruction, and treatment was offered to those who consented. The safety of SWL was assessed by the need for interventions and the posttreatment renal function. RESULTS: In 14 patients lithotripsy was uneventful. The duration of treatment ranged from 5 to 35 days. One patient with a 15-mm pelvic calculus presented with anuria which resolved before intervention. In 1 patient fragmentation failed, and percutaneous nephrolithotomy was performed. CONCLUSIONS: In solitary functioning kidneys, SWL is safe without prophylactic stents in properly selected and closely monitored patients. Avoiding stents decreases costs, duration of treatment, and stent-related morbidity without unduly compromising safety.     

移植肾尿路结石的腔内治疗

目的探讨腔内治疗移植。肾尿路结石的效果和策略。方法采用腔内技术治疗13例移植。肾尿路结石，其中。肾结石3例，金属支架结石1例，输尿管结石9例，合并输尿管口狭窄2例。结石最大直径8～48mm，接受肾移植的时间1个月～8年。结果3例。肾结石和1例金属支架结石行经皮微造瘘输尿管镜取石术成功取石。4例输尿管结石行逆行输尿管镜取石治疗；3例行经皮顺行输尿管镜取石成功，其中1例合并移植输尿管口狭窄者同时行内切开取石；1例移植输尿管口狭窄合并下端结石者，改行开放手术；1例输尿管结石直接行体外冲击波碎石术2次后排净结石。术后随访1～8年，人肾存活均良好，12例患者。肾功能恢复正常，无结石复发。结论移植肾尿路结石处理应选择创伤小、效果好的腔内微创治疗，尽可能保护。肾功能。     

Raising of the treatment efficacy of renal colic and prophylaxis of acute calculous pyelonephritis in patient with ureterolithiasis

In 116 patients with renal colic, caused by stones of ureters, conservative treatment with application of hyperbaric oxygenation (HBO) was conducted. Under the influence of oxygenotherapy during 3 days obstruction of the urinary tracts in all patients had disappeared as well as acute urostasis, clinic symptoms of the renal colic, progress of an acute infectious-inflammatory process stopped, complications were eliminated. Echo-positive subjects had disappeared from kidneys, in one patient renal calculus had dissolved, in 5--calculi had reduced in size and fragmentated, in 9--had not changed. In 108 patients the ureters had freed from calculi, in 8--calculi had reduced in size and migrated in distal direction.     

肾盂切开气压弹道碎石治疗鹿角形肾结石(附46例报告)

目的 探讨肾盂切开气压弹道碎石治疗鹿角形肾结石的疗效。方法 对46例鹿角形肾结石采用肾盂切开气压弹道碎石，将结石分解成数块，再逐一取出。双侧肾结石采用一次分侧手术取石。结果 46例鹿角形肾结石均较顺利取出，无黏膜撕脱、出血等并发症。25例肾功不全者均显著改善。结论肾盂切开结合气压弹道碎石是治疗鹿角形肾结石较好方法；双侧肾结石多有梗阻致肾功能受损，应双侧一次取石，有利于双肾功能恢复。     

Improvement in serum creatinine following definite treatment of urolithiasis in patients with concurrent renal insufficiency

OBJECTIVE: To assess whether definitive treatment of urolithiasis following relief of obstruction in patients with renal insufficiency results in further improvement in renal function as determined by serum creatinine. METHODS: In a review of 500 patients with urolithiasis, we identified 43 (12%) patients with serum creatinine level of > or =176 micromol/l at the time of presentation. Location and complexity of calculi, type of procedure required to render the patients stone free and effects of surgical intervention (following relief of obstruction) on renal function were evaluated. RESULTS: Mean serum creatinine at presentation was 555 micromol/l and after relief of obstruction was 361 micromol/l. Mean serum creatinine level after surgical intervention dropped to 193 micromol/l (p < 0.001). Complete or partial staghorn calculi were seen in 40% of patients. Two-thirds of patients required more than one procedure for complete stone clearance. CONCLUSIONS: Renal calculi and concurrent mild to moderate renal insufficiency warrants aggressive treatments. Patients demonstrate significant improvement in renal function independent of relief of obstruction.     

微创经皮肾取石术治疗先天性异常肾合并结石

目的探讨微创经皮肾镜取石术（minimally invasive percutaneous nephrolithotomy,MPCNL）治疗先天性异常肾合并结石的疗效。方法2000年1月～2007年11月,采用MPCNL治疗异常肾合并结石41例,其中马蹄肾12例,重复肾19例,旋转肾10例。单发上盏结石4例,中盏6例,下盏7例,肾盂结石3例,重复肾上肾结石4例,多发结石12例,鹿角形结石5例。结石最大直径1.0～4.0 cm,平均2.5 cm。13例合并输尿管中上段结石同时取石。结果41例均一次穿刺成功。手术时间45～210 min,平均95 min。术中出血30～150 ml,平均80 ml。一期结石清除率85.4%（35/41）,2例马蹄肾和1例重复肾患者经二次取石取净,2例重复肾和1例旋转肾患者术后配合体外冲击波碎石治疗。1例旋转肾MPCNL术后发生较严重出血（800 ml）,经高选择性动脉栓塞后治愈,其余未见严重并发症发生。41例随访5～12个月,平均6个月,无结石复发。结论MPCNL治疗先天性异常肾合并结石安全、可靠。但仍需强调个体化的原则,根据不同异常肾的类型,结石大小、位置等情况进行操作。     

Renography as a measure of renal and neobladder function in patients with ileal bladder substitution

INTRODUCTION: Using renography, we evaluated the function of both the kidneys and neobladder of 20 patients who underwent ileal bladder substitution. METHODS: The patients were measured for renal and neobladder function with renography using 99mTc MAG3. Renal function was assayed in every renal unit using O'Reilly patterns. Voiding function was estimated using radioisotope counts for the reservoir. RESULTS: Thirty-two of 37 renal units had normal renograms. Five renal units showed non-obstructive renograms. The percentage of total residual urine (RU) in the reservoir was 30% and more in 6 patients, 10-30% in 8, and <10% in 6. In 7 of 12 patients, the data on estimated RU correlated with the data on measured RU. However, in 5 patients, the data on estimated RU increased more in quantity than the data on RU measured at another time. CONCLUSIONS: In patients with bladder substitution the functions of both the kidneys and neobladder could be evaluated in a single renography.     

MANAGEMENT AND OUTCOME OF ANTENATALLY DIAGNOSED HYDRONEPHROSIS

From March 1989 to December 1992, we encountered 25 kidneys in 21 patients with a suspicious ureteropelvic junction (UPJ) obstruction detected only on prenatal ultrasound. In all these patients other urological abnormalities were excluded by voiding cystourethrography and other radiological findings. Diuretic renography (DR) was initially performed at an age ranging from 15 days to 32 months in all patients and repeated a total of 39 times. Both the split renal function (SRF) and diuretic drainage half-time clearance (DT1/2) of radioagent were within their normal ranges in the case of 15 (60%) of the kidneys on initial DR. In these kidneys, there were no aggravated signs on repeated DR. Decreased SRF was found in 3 kidneys (12%) on initial DR. Of these, the renal function spontaneously reverted to normal in 2 cases with bilateral hydronephrosis. Another 1 kidney revealed significant UPJ obstruction assessed by pressure flow study and continuous nephrostomy drainage had brought relief from the obstruction 1 year later. Prolonged DT1/2 with normal SRF was found in 7 (28%) kidneys. The renal function did not deteriorate and the diuretic response improved on repeat DR except for 1 kidney, whose function deteriorated and on which ultimately, pyelo-plasty was performed at 7 months of age. Prenatally diagnosed hydronephrosis is usually asymptomatic and clinically significant UPJ obstruction should be always verified. Although even today there is still no examination which can detect a definite obstruction, we can identify one as significant by careful repeat examinations and thus avoid unnecessary surgery without causing any renal deterioration.     

The use of renal scintigraphy in assessing the potential for recovery in the obstructed renal tract in children.

OBJECTIVE: To assess the value of renal scintigraphy with 99mTc-dimercaptosuccinic acid (DMSA) in predicting functional recovery after the surgical relief of obstructed kidneys in children. Patients and methods Forty-three children underwent surgery to relieve upper urinary tract obstruction; 37 had pelvi-ureteric junction obstruction and six had vesico-ureteric junction obstruction. The indication for surgery was a combination of an obstructed renogram with symptoms of either pain or pyelonephritis. Most children (41) had < 40% function on the affected side before surgery, with just two having hyperfunction (> 55%). In all patients intravenous urography before surgery showed hydronephrosis, and a micturating cystogram was used to exclude coexisting reflux in the presence of an associated megaureter. Diuretic renography (using 99mTc-mercaptoacetyl triglycine or 123I-hippuran) and DMSA scintigraphy were both carried out before surgery and the renography repeated 6 months afterward. RESULTS: The renographic drainage curves improved from obstructed to unobstructed or 'dilated unobstructed' on all postoperative studies. Regression analysis showed that preoperative DMSA scan was an excellent predictor of outcome (P < 0.001) whilst the preoperative renogram was a relatively poor predictor of the functional result. In four patients where the initial renographic function was < 10%, DMSA scintigraphy predicted correctly the capacity for recovery in three and the inability to improve in the fourth. Conclusion Before surgery, DMSA scintigraphy in children with upper urinary tract obstruction is a more useful estimate of probable long-term renal function than value from diuresis renography. If there is doubt about the desirability of reconstructive surgery, a DMSA scan may eliminate the need for more invasive methods of estimating recovery, e.g. a period of nephrostomy drainage.     

Effective renal plasma flow: clinical significance after spinal cord injury

We conducted a study to determine if effective renal plasma flow routinely measured by hippurate clearance during a comprehensive renal scintillation procedure is a relevant measure for assessing renal function in spinal cord injury patients. All subjects had spinal cord injury and had had contemporaneous comprehensive renal scintillation procedures and excretory urograms on 2 occasions 24 months or less apart. Each of the 469 kidneys was placed into 1 of 5 quintiles on the basis of its effective renal plasma flow at the first examination. The percentage of the kidneys that had clinically significant pyelocaliectasis or in which the pyelocaliectasis significantly worsened was 20.4 per cent in the lowest (first) quintile and 9.3, 2.2, 5.4 and 3.2 per cent in the second, third, fourth and fifth quintiles, respectively. Analogous data for ureterectasis were 16.1, 8.2, 2.2, 3.3 and 3.2 per cent. There was a significant (p less than 0.01) correlation between effective renal plasma flow and renal parenchymal thickness. Kidneys with renal calculi averaged effective renal plasma flows about 25 per cent lower than those of kidneys free of calculi. We conclude that effective renal plasma flow is a relevant measure for assessing renal function in spinal cord injury patients.     

Impaired drainage on diuretic renography using half-time or pelvic excretion efficiency is not a sign of obstruction in children with a prenatal diagnosis of unilateral renal pelvic dilatation

PURPOSE: Delayed drainage on diuretic renography is an accepted sign of obstruction in adults and symptomatic children. We investigated how to analyze the diuretic challenge as well as assess the significance of impaired drainage. MATERIALS AND METHODS: We followed 24 children with a unilateral prenatal diagnosis of pelvic dilatation up to a minimum of 2 years. A total of 91 diuretic renograms were performed. All children had stable differential renal function and renal pelvic diameter did not change by greater than 9 mm. on sequential ultrasound. Kidneys with stable differential function and no increase in dilatation were considered not obstructed. Analysis of the diuretic challenge included half-time, a post-void image with a change in posture, that is the child erect for 5 to 7 minutes, and drainage considering renal function using the pelvic excretion efficiency. Prolonged drainage was defined as a half-time of greater than 20 minutes or a post-void pelvic excretion efficiency of less than 71%. RESULTS: Median patient age at presentation was 0.32 years and median followup was 3.07 years. The affected nonobstructed hydronephrotic kidney showed impaired drainage in 68% of the children using the half-time parameter, and in 80% and 44% using pelvic excretion efficiency before and after voiding, respectively. Variability in drainage was documented on sequential diuretic renography. CONCLUSIONS: Using the guidelines for data acquisition and processing of diuretic renograms we nevertheless noted impaired drainage in 44% of this young group with nonobstructed kidneys. The half-time parameter was an inappropriate parameter. The diagnosis of obstruction cannot be simply based on delayed drainage in this group of asymptomatic children with a prenatal diagnosis of unilateral renal pelvic dilatation.     

Comparison of conventional radiography combined with ultrasonography versus nonenhanced helical computed tomography in evaluation of patients with renal colic

The aim of this study is to determine whether kidneys ureters bladder X-ray (KUB) film combined with ultrasound (US) can be effectively used in evaluation of renal colic and miss stones with clinically significant size identified on nonenhanced computed tomography (NECT) in patients with urolithiasis. This retrospective study evaluated the clinical and radiological records of 300 patients at our institution undergoing KUB and/or US and/or NECT for the evaluation of renal colic from June 2007 to December 2010. Of patients with negative findings on KUB and/or US, 22 had renal stones on NECT (mean size 4.4?mm, range 3-8), 3 had lower ureteral stone (mean size 3.3?mm, range 2-5). In patients with isolated suspicious renal ectasia without stone image, two had renal stone on NECT (mean size 4?mm, range 2-6), 5 had upper ureteral stone (mean size 4.4?mm, range 4-6), 7 had middle ureteral stone (mean size 3.7?mm, range 3-4) and 14 had lower ureteral stone (mean size 4?mm, range 2-6). The cost-effective and almost radiation-free combination of KUB and US should be preferred for diagnosis of urolithiasis, as it detects most of the ureteral and renal calculi which are clinically significant.     

Natural history of pelviureteric obstruction detected by prenatal sonography

Fifty-six infants with prenatally diagnosed hydronephrosis are reported. In all instances the diagnosis was confirmed postnatally and at renography 45 were obstructed; 38 obstructed kidneys (84%) and all of the non-obstructed kidneys had a differential function exceeding 40% of total function. Latterly we have come to recommend early pyeloplasty only if differential function of a renographically obstructed kidney is less than 40%; 6 early pyeloplasties were performed for this reason; 28 infants (30 renal units) were managed non-operatively and 18 of these (19 renal units) were reassessed renographically. In 11 the obstruction persists. Sonography demonstrated improving hydronephrosis in 8 kidneys with resolution in 5 and no change in 6. Of the other 10 infants (11 renal units), the hydronephrosis has improved in 4, resolved in 1 and remains unchanged in 6. Our experience suggests that neonatal and early pyeloplasty can be restricted to a modest number of infants in whom there is impaired renal function. In cases with normal function the natural history appears essentially benign and does not justify routine pyeloplasty.     

Progression of nephrolithiasis: long-term outcomes with observation of asymptomatic calculi

BACKGROUND AND PURPOSE: Observation is often recommended for patients presenting with asymptomatic renal calculi. This study evaluated the natural history of asymptomatic calculi and the risk of progression of disease. PATIENTS AND METHODS: We conducted a retrospective evaluation of 300 male patients average age 62.8 years who were followed for a mean of 3.26 years for asymptomatic renal calculi in an outpatient urology clinic. At presentation, the mean cumulative stone diameter was 10.8 mm; 56% were lower-pole stones, and 48% of the patients had multiple calculi. Patients underwent annual radiographic imaging and clinic visits with standardized questions regarding the development of symptoms or complications from calculi. Progression of disease was defined as the need for surgical intervention, the development of pain, or stone growth on serial imaging. RESULTS: Overall, 77% of patients experienced disease progression, with 26% requiring surgical intervention. Stone size was positively associated with progression: those with an isolated stone >/=4 mm on presentation were 26% more likely to fail observation than patients with smaller solitary calculi (P = 0.012). Stone growth was less common in those with upper-pole and middle-pole stones (47% v 61%) for lower-pole stones; P = 0.002). Urine uric acid concentration correlated positively with the rate of stone growth (P = 0.05). Likewise, serum uric acid concentration predicted stone growth (odds ratio = 3.6). CONCLUSIONS: Stratification of risk of progression according to presenting stone size, location, and composition may facilitate discussions with the patient regarding the alternatives of observation versus intervention. Specifically, small non-uric acid calculi in the upper pole may be most amenable to observation.     

Laparoendoscopic single-site (LESS) pyeloplasty for horseshoe ureteropelvic junction obstruction

Background and Objective:

Pyeloplasty in horseshoe kidneys can be challenging due to aberrant vasculature, renal malrotation, and ectopic location. Fewer than 20 cases of minimally invasive (MIS) pyeloplasty in horseshoe kidneys have been reported in the literature to date. We herein report the first 2 cases of laparoendoscopic single-site (LESS) pyeloplasty for UPJ obstruction in horseshoe kidneys.

Methods:

Two patients with symptomatic ureteropelvic junction obstruction in horseshoe kidneys were treated with an Anderson-Hynes LESS pyeloplasty. This was performed using three 5-mm trocars through a single umbilical incision, plus an accessory 3-mm port at the anterior axillary line to facilitate suturing and subsequent drain placement.

Results:

Both patients had BMI <23. The operative times were 204 minutes and 171 minutes. Blood loss was negligible, and no intraoperative complications occurred. To date, 9-month renography for patient 1 demonstrates stable renal function and unobstructed drainage. After stent removal, patient 2 was asymptomatic.

Conclusion:

In experienced hands, LESS reconstructive techniques are applicable to complex renal anomalies. LESS pyeloplasty for UPJ obstruction associated with horseshoe kidneys is feasible, safe, and effective in select patients.     

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.