Urologist-Acquired Renal Access for Percutaneous Renal Surgery

Objectives. In most endourology programs an interventional radiologist is employed to acquire renal access for percutaneous renal surgery. Over the last 13 years the senior endourologist at Oregon Health Sciences University has acquired access without employing a radiologist. We report our experience with urologist-acquired renal access for percutaneous renal surgery in 522 cases.Methods. We reviewed the records of all patients at our hospital who underwent percutaneous renal surgery between August 1983 and December 1996 with renal access being obtained in the operating room by a urologist.Results. Four hundred fifty-six patients underwent 522 procedures. Indications for percutaneous renal surgery were renal and proximal ureteral calculi (n = 516), retained ureteral stent (n = 3), and intrarenal collecting system tumor (n = 3). We were successful in gaining access to 513 of 522 kidneys (98.3%). Access was obtained via a subcostal approach in 344 procedures, over the 12th rib in 152 procedures, over the 11th rib in 15 procedures, and transabdominally in 2 procedures. Sixty-five patients (12.7%) required a second or multiple sites to facilitate complete removal of calculi. Our overall complication rate was 15.3%. Blood transfusion was required in 5.4% of the cases, ileus developed in 1.9%, pneumothorax in 1.1%, intraoperative hydrothorax in 1.1%, postoperative pleural effusion requiring aspiration in 0.9%, and septic shock in 0.9%. Our overall success rate for stone removal was 94.5%.Conclusions. In our experience, the urologist is able to safely and effectively obtain percutaneous access to the collecting system for percutaneous renal surgery as a one-stage procedure without the aid of interventional radiologists.     

Bilateral Renal Angiomyolipoma

Angiomyolipomas are frequent tumours of the kidneys. They are very important in the differential diagnosis of other kidney tumours; sometimes they can present a large size and manifest as an acute massive retroperitoneal haemorrhage. They generally should not be treated unless there are life-threatening problems. In this case report, we present an acute surgical condition due to rupture and haemorrhage of a giant angiomyolipoma. In addition, we review the literature on angiomyolipomas and their severe complications in order to help young surgeons who may be involved in such difficult and life-threatening cases as ours.     

Renal allograft immunosuppression

The long-term effects of different immunosuppressive drugs and regimens on renal allograft histology are virtually unknown. Therefore, in order to investigate the long-term effects of triple drug treatment versus different combinations of two immunosuppressive drugs on allograft histology, a prospective, randomized trial was performed. One group received triple therapy consisting of low-dose cyclosporin (CyA), azathioprine (Aza), and methylprednisolone (MP), and three groups received combinations of two drugs, i.e., Aza plus CyA, Aza plus MP, and CyA plus MP. At 2 years, there were no significant differences with regard to graft (80%) or patient (87%) survival, or to graft function between the four groups. After 2 years, a protocol core biopsy was taken of all 102 patients having a functioning graft. Of these patients, 61 (60%) were still following the original, randomized treatment protocol; in the remaining cases, changes had occurred in the original protocol and so these cases were considered drop-outs in this study. Histological specimens were examined blindly by two independent observers. Most of the 34 histological variables examined showed no changes. Diffuse fibrosis was most frequent in the CyA plus MP group (70%) and significantly more severe than in the triple therapy group. Mesangial matrix increase in glomeruli was significantly less common in the triple therapy group (8%) than in any one of the double drug combination groups (47%). Two other changes in glomeruli--Bowman capsular thickening and global glomerular sclerosis--were also less frequent in the triple therapy group.(ABSTRACT TRUNCATED AT 250 WORDS)     

Renal allograft immunosuppression

A prospective randomized study was conducted to evaluate the impact of four different conversion protocols on graft outcome in long-term follow-up. Between January 1986 and May 1987, 128 patients with first cadaveric kidnery allografts were randomized at the time of transplantation to four treatment groups of 32 patients each, to be assigned 10 weeks post-transplantation. During the first 10 weeks, all patients received triple therapy with low-dose azathioprine (Aza), cyclosporin (CyA), and methylprednisolone (MP). After 10 weeks, one group continued with triple therapy (group A) while the three other groups received different combinations of two drugs, namely, Aza and CyA (group B), Aza and MP (group C), or CyA and MP (group D). Withdrawal of MP (group B) or especially of CyA (group C) was associated with 4/29 (14%) and 10/28 (36%) acute rejection episodes, respectively, for 60 days after conversion. All rejections were mild and reversible. There were no rejections after Aza withdrawal or in the group that continued on triple therapy during the corresponding time period. The most common reason for dropping out after withdrawal, for those patients who could not continue on the originally randomized medication, was azathioprine intolerance (n=12). Five patients were switched back to triple therapy after CyA withdrawal due to rejection. Steroid intolerance was rare and CyA in low doses was very well tolerated. At 1 year there were no statistically significant differences in graft survival between groups A, B, C, and D-81%, 88%, 88%, and 88%, respecively-or in patient survival-88%, 88%, 88%, and 97%, respectively. For those patients continuing with the originally randomized treatment protocol, there were no differences in patient or graft survival either, the means being 91% and 89%, respectively. The most common cause of death after withdrawal was cardiovascular in nature, and there were no more fatal infections under triple drug treatment than with double drug regimens. There were no statistically significant differences in mean serum creatinine values at 1 year. The median serum creatinine values for groups A, B, C, and D were 112, 132, 133, and 133 mol/l, respectively. At 1 year the mean CyA dose in the groups that continued with CyA was 3.5–4.2 mg/kg per day and CyA concentrations were equal.     

Laparoscopic Versus Open Renal Procurement for Pediatric Recipients of Living Donor Renal Transplantation

Despite reports demonstrating the safety of laparoscopic donor nephrectomy (LDN) for pediatric recipients of renal transplants, recent evidence has challenged using LDN for recipients 5 years of age or younger. We retrospectively reviewed the records of all pediatric recipients of living donor renal transplants from September 2000 through August 2004. We compared those who received allografts recovered by LDN (n = 34) with those recovered by open donor nephrectomy (ODN, n = 26). Outcomes of interest included operative complications, postoperative renal function, the incidence of delayed graft function or episodes of acute rejection and long-term graft function. Donor and recipient demographic data were similar for the LDN and ODN groups. Serum creatinine and calculated creatinine clearance were not significantly different between groups both in the early postoperative period and at long-term follow-up (p > 0.142). Rates of delayed graft function and acute rejection did not differ between groups. Among recipients aged 5 years old or younger stratified by donor technique (9 LDN, 5 ODN recipients), no difference was noted in graft outcomes both early and long-term (p > 0.079). At our center, pediatric LDN recipients have graft outcomes comparable to those of ODN recipients. At experienced centers, we recommend continued use of LDN for pediatric recipients of all ages.     

原位低温阻断肾血管肾实质切开取石术

目的探讨原位低温阻断肾血管肾实质切开取石术治疗复杂性肾结石的效果。方法2000年3月～2005年1月采用原位低温阻断肾血管肾实质切开取石术治疗肾内型肾盂复杂性肾结石患者22例,术中快速静脉滴注肌苷2.0g,静滴20%甘露醇250ml。根据术前影像检查结果及术中所见选择肾切口径路:13例充填于各盏的鹿角状结石,行肾背侧Brodt线肾实质肾盏切开取石;5例肾下盏肾盂鹿角状结石,行肾盂肾实质联合切开取石;4例结石过多者,于肾皮质最薄处另作放射状切口取石。结果肾血管阻断时间平均45(30～60)min;手术时间平均110(90～180)min;平均失血量150(80～400)ml。结石一次取净21例,1例残余结石,术后2个月带双J管行ESWL碎石排出。术后1～2月复查肾功能,术前有肾功能损害的8例,血清Cr平均110.2μmol/L,血清BUN平均8.0mmol/L,均明显改善,其余患者肾功能无损害,无严重术后并发症。18例随访6个月～3年无一例复发。结论原位低温阻断肾血管肾实质切开取石术治疗复杂性肾结石安全有效、出血少、结石残留率低。     

Renal function in patients with nephrolithiasis

PURPOSE: We describe kidney function, as measured by creatinine clearance in stone formers, and classified by type of stone formed and systemic etiologies of stone formation. MATERIALS AND METHODS: The mean of 3 pretreatment 24-hour creatinine clearance measurements in each of 1,856 stone formers and creatinine clearance in 153 normal individuals were used. Clearance was adjusted for patient sex, age and body weight using general linear modeling. RESULTS: As a group, all stone formers had decreased clearance adjusted for age, sex and body weight compared to that in normal individuals. Although clearance was particularly low in cystine and struvite stone formers, they were below normal in even common CaOx stone formers. CONCLUSIONS: As a rule, patients with kidney stones do not have normal kidney function. In clinical management all efforts must be made to minimize renal injury, balancing the risks of obstruction from stones against those of urological procedures.     

肾切除前肾蒂间歇性阻断促进留存肾代偿性生长的初步研究

为探讨肾切除前肾蒂间歇性阻断对留存肾代偿性生长的影响,用45只Wistar雄性大白鼠随机分为三组,分别行在肾切除(N组),肾蒂间歇性阻断后左肾切除(P组),肾蒂间隙阻断方法为夹闭肾蒂5分钟,松开5分钟,如此重复5次)及假手术(S组)。以术后14天留存肾(右肾)肾重及肾重/体重比值判断肾代偿性生长程度。结果P组肾切除术后留存肾代偿性生长较N组更为明显。表明肾切除前肾蒂间歇阻断明显促进了留存肾的代偿性生长。其机制还有待进一步研究。     

肾损伤出血的超选择性肾动脉栓塞治疗

目的总结超选择性肾动脉栓塞在肾损伤出血治疗中的应用效果。方法2001年1月~2006年12月12例肾损伤血尿患者,肾结石肾积水行切开取石术后7例,肾穿刺活检术后2例;肾脏闭合性损伤2例,刀刺伤1例。行超选择性肾动脉栓塞术,以弹簧圈(5例)、PVA(6例)、丝线(1例)进行栓塞。结果术中证实12例均为肾段或肾段以下动脉损伤,术后所有病例新鲜出血立即停止,随访1~3个月,效果良好,未见有肾血管性高血压。结论肾损伤出血以超选择性插管栓塞为佳。     

Renal regeneration after acute kidney injury

Acute kidney injury is common and associated with negative renal and patient outcomes. The human kidney has a real but limited regeneration capacity. Understanding renal regeneration may allow us to manipulate this process and thus develop therapeutic weapons to improve patients’ outcome. In the first part of this paper we discuss the clinical factors associated with renal recovery: baseline patient particularities, acute kidney injury characteristics and the medical approach taken in the short and long‐term. In the second part, the cellular and molecular mechanisms underlying renal regeneration are explored. The immune system seems to have an important role, first promoting inflammation and then tissue healing. Other players, such as cellular senescence, mitochondrial dysfunction, renal haemodynamics and metabolic reprogramming also have a role in renal regeneration. We aim to develop a short review of renal regeneration, offering a holistic view of this process.     

Renal allograft immunosuppression

Serum lipid and lipoprotein profiles were performed in order to investigate lipid abnormalities 2 years post-transplantation in first cadaveric renal allograft recipients immunosuppressed with cyclosporin (CyA), azathioprine (Aza), and methylprednisolone (MP), or with any combination of two drugs. CyA was used in low doses. Total serum cholesterol, triglyceride, LDL cholesterol, HDL cholesterol, HDL2 cholesterol, HDL3 cholesterol, apolipoprotein A1, and apolipoprotein B were determined in 88 prospectively randomized patients with functioning grafts. When considering only the patients who remained on the original randomized treatment, there were no significant differences between the four groups in any of the measured variables. Mean total cholesterol was highest in the group receiving Aza and MP (6.8 mmol/l) and lowest in the group receiving triple therapy (5.8 mmol/l; NS). Mean triglyceride level was highest in the group receiving Aza and MP (2.3 mmol/l) versus 1.8–2.2 mmol/l in the groups receiving triple therapy, Aza+CyA, and CyA+MP. For all patients mean triglyceride level was highest in the group receiving Aza and MP (2.7 mmol/l) and lowest in the group receiving triple therapy (1.7 mmol/l; P<0.05). Mean HDL cholesterol ranged from 1.5 to 1.6 mmol/l in all groups. Neither CyA concentration nor CyA or MP dose correlated with cholesterol or triglyceride concentration. However, the average MP dose was twice as high in the group receiving Aza and MP as in the other two groups employing steroids. Serum cholesterol and triglyceride concentrations were related to body mass index (r=0.28, P=0.045 and r=0.30, P=0.029, respectively). Hyperlipidemia was most common in the group receiving Aza and MP. The frequency of hypercholesterolemia (serum cholesterol level >6.5 mmol/l) was 18%, 45%, 60%, and 35% for the patients continuing with the originally randomized treatment in the groups receiving triple therapy, Aza+CyA, Aza+MP, and CyA+MP, respectively. In a normal Finnish reference population, 35% of all males and 31% of all females have a serum cholesterollevel above 6.5 mmol/l. Thus, only patients receiving Aza and MP had a clearly higher frequency of hypercholesterolemia than that found in a normal population. Taken together, this study shows no lipid abnormalities associated with the use of low-dose CyA for 2 years after transplantation. Hyperlipidemia occurring after transplantation is probably multifactorial and more associated with other risk factors than with the immunosuppressive therapy.     

Renal cell carcinoma and end stage renal disease

PURPOSE: Patients with ESRD secondary to acquired renal cystic disease have been reported to have a higher incidence of RCC than the general population. We examined the clinical and pathological significance of incidental renal masses in patients with ESRD. MATERIALS AND METHODS: From January 1994 to July 2000, 852 consecutive patients with ESRD who were being considered for renal transplantation at University of Mississippi Medical Center were evaluated with renal ultrasound as part of assessment for possible kidney transplantation. Those patients with ultrasound suspicious for a malignant renal lesion were further evaluated with CT of the abdomen with and without intravenous contrast medium. Any patient with CT findings suspicious for RCC was recommended to undergo radical nephrectomy before kidney transplantation. RESULTS: A total of 19 patients had CT criteria for a possible malignant renal lesion. Seven patients had Bosniak class 3 renal cysts and 12 patients had solid, enhancing renal masses. Of the patients 17 underwent radical nephrectomy. On pathological examination 14 patients had RCC with a 1.64% prevalence in the population screened. Mean Fuhrman nuclear grade in our patients was 2.45. CONCLUSIONS: RCC in patients with ESRD are of clinical significance, considering the size, grade, histology and pathological stage of these tumors. The higher prevalence of clinically significant RCC in patients with ESRD as well as the risk of cancer progression while patients are on immunosuppressive medications justifies screening for RCC in patients with ESRD who are awaiting renal transplantation.