Pressure effects of urinary reflux studied with renal autotransplantation and pyelocystostomy

Evaluation of two nephrocystostomy techniques for ureteral bypass in cats

OBJECTIVE

To describe two techniques for nephrocystostomy (NCT) in cats.

STUDY DESIGN

Experimental study.

ANIMALS

Twelve, adult, purpose-bred, cats.

METHODS

A simple NCT (n = 3) or bladder cuff NCT (n = 9) was performed in the right or left kidneys. For simple NCT, an 8F catheter was placed through the caudal pole into the renal pelvis and the bladder was sutured around the catheter. For bladder cuff NCT, a 6 mm defect was removed from the caudal pole and a cuff of bladder mucosa was advanced and sutured into the renal pelvis. A 10F catheter was placed through the defect into the renal pelvis and the bladder wall was sutured around the catheter. Catheters were removed 41-118 days post-surgery. Computed tomography (CT) was performed 25 days after catheter removal for the simple NCT and 30 (n = 6) and 90 (n = 3) days after catheter removal for bladder cuff NCT. Histological evaluation of the nephrocystostomy site was performed.

RESULTS

All simple NCTs became obstructed after catheter removal. All bladder cuff NCTs were patent, and CT revealed contrast flow into the bladder. Hematuria, clot-associated urethral obstruction, catheter dislodgement, and bladder infection occurred variably after surgery. Histological findings consisted of smooth epithelialization of the NCT and degenerative changes in the caudal pole of the kidney.

CONCLUSION

Bladder cuff NCT was feasible in normal cats and remained patent for 90 days. Methods to limit nephrostomy track hemorrhage should be investigated. Degenerative changes may be related to vascular impairment from the bladder cuff sutures.

CLINICAL SIGNIFICANCE

Complete ureteral bypass was possible in cats using only native tissues.

Pyelovesicostomy as an Alternative Surgical Treatment for Complex Ureteral Lesions After Kidney Transplant

OBJECTIVES

We evaluated the feasibility, safety, and long-term outcomes of pyelovesicostomy as an alternative surgical treatment for complex ureteral lesions after kidney transplant.

MATERIALS AND METHODS

A single-center, retrospective, observational cohort study was conducted on 5 adult kidney transplant recipients who underwent pyelovesicostomy between January 2000 and June 2023. The collected data included patient demographics, surgery indication, time from transplant to pyelovesicostomy, procedure details, and kidney function at various time points after surgery. Primary outcomes were allograft function and complications.

RESULTS

The 5 patients (4 female, 1 male) had a mean age of 65.8 years and mean body mass index of 26.8. Indications were complex ureteral lesions. The time between transplant and reoperation ranged from 4 days to 12 years. Renal function improved for all patients, with a progressive decrease in mean serum creatinine concentration. The mean follow-up period extended to 7 years. One patient died with the graft still functional at 20 years after the operation, whereas the remaining 4 patients continue to live with functional grafts.

CONCLUSIONS

Our study suggests that pyelovesicostomy may provide a potent alternative for the management of complex ureteral lesions after kidney transplant. We have observed good short-term and long-term outcomes in specific patients, pointing toward a promising avenue oftreatment worth further exploration. This reaffirms the importance of a personalized approach in medicine, to consider each patient's unique conditions and characteristics during therapeutic decisions.

Robot-assisted boari flap calycovesicostomy for failed uretero-pelvic junction obstruction: a novel approach to a complex problem

Uretero-pelvic junction obstruction (UPJO) is a common condition, often presenting in adulthood in developing countries. These cases can pose significant problems owing to late presentation and complications such as infection, stones, and impaired renal function. We present the case of a 28-year-old female who presented to us with recurrent symptoms and impaired drainage following a failed open pyeloplasty and robot-assisted ureterocalycostomy for right UPJO. She was managed by robot-assisted boari flap calycovesicostomy, an innovation which helped in salvaging her kidney; ensuring good drainage in the involved kidney. To our knowledge, this is the first such case in the literature in the management of complex UPJO.

Bilateral simultaneous "Santosh Post-graduate Institute tubularized flap pyelovesicostomy" in a case of bilateral pelvi-ureteric junction obstruction with bilateral giant hydronephrosis

We present a case of bilateral giant hydronephrosis (HDN) secondary to bilateral pelvi-ureteric junction obstruction (PUJO) in a young girl, managed successfully by robot-assisted bilateral tubularized flap pyelo-vesicostomy. This case report highlights the feasibility, reproducibility and technicalities of this procedure.

Robot-assisted "Santosh-Post Graduate Institute tubularized flap pyelovesicostomy" in a solitary functioning kidney with giant hydronephrosis: A minimally invasive salvage procedure

We describe a case of a solitary functioning kidney with giant hydronephrosis secondary to ureteropelvic junction obstruction in a young girl who underwent successful robot-assisted tubularized flap pyelovesicostomy. The aim of this report was to highlight the feasibility and efficacy of this technique in salvaging such renal moieties and to present a brief review of the surgical options available for the management of giant hydronephrosis.

A simple ileal substitute bladder after radical cystectomy: experience with a modification of the Studer pouch

Bladder substitution using pouches designed from detubularized bowel is gaining widespread acceptance among urologists and their patients. However, few clinical reports have described the effectiveness of the orthotopic neobladder fashioned from ileum in the manner described by Studer. Since 1988, we have used the Studer technique with minor modifications in 20 men who underwent radical cystoprostatectomy for transitional cell carcinoma of the bladder. Early morbidity from the procedure was minimal, although 2 patients later had anastomotic strictures. Significant late complications included low vitamin B12 levels in 4 patients and persistent hyperchloremia in 1. A total of 18 patients achieved diurnal continence but 9 of these had enuresis. Neobladder compliance and emptying were satisfactory in the 12 patients evaluated urodynamically. Upper tracts remained stable in all patients at a median followup of 24 months (range 9 to 60). Isolated episodes of bacteriuria occurred in 11 patients but followup urine cultures have remained sterile in all continent patients. The Studer ileal neobladder is a simple, effective alternative for urine storage, upper tract preservation and efficient voiding.

Vesicopyeloplasty in renal transplant patients: a 20-year followup

Loss of a ureter in a renal transplant patient often results in transplant nephrectomy. In 1973 we used vesicopyelostomy with the bladder directly sutured to the renal pelvis as a method of reconstruction in 2 renal transplant patients following ureteral loss. These patients have been followed for more than 20 years and both renal allografts have functioned well. The status of these patients and a review of the literature on vesicopyelostomy are presented.

Balloon dilation of the distal ureter to 24F: an effective method for ureteroscopic stone retrieval

Early in our ureteroscopic experience, in an effort to facilitate retrieval of ureteral calculi with the 11.5F and 12.5F rigid ureteroscopes, the distal ureter was routinely balloon dilated to 24F. Among 131 ureteroscopic procedures all consecutive 108 distal ureteral calculi were successfully removed. However, only 65% of 23 upper ureteral calculi were extracted. A followup excretory urogram (6 weeks or later) in 86 patients revealed no distal ureteral strictures. A followup cystogram in 30 patients showed low grade vesicoureteral reflux in 20% of the patients and none of these individuals was symptomatic. As such, balloon dilation of the distal ureter to 24F appears to be well tolerated. Presently, given the advent of smaller ureteroscopes and lithotriptor probes, such extensive ureteral dilation is necessary only in a minority of patients with distal ureteral calculi. In these few patients with calculi resistant to lithotripsy balloon dilation of the ureter to 24F may allow for successful, safe stone extraction, thereby precluding open ureterolithotomy.

The role of renal autotransplantation in complex urological reconstruction

From 1972 to 1988, 108 patients underwent renal autotransplantation for renal artery disease (67), ureteral replacement (27), or renal cell carcinoma present bilaterally or in a solitary kidney (14). The most common indication for renal autotransplantation was to allow extracorporeal repair of complex branch renal artery lesions. Of the 54 patients in this group technically satisfactory branch renal arterial reconstruction and a successful clinical outcome were achieved in 52 (96%). Renal autotransplantation is the treatment of choice in these patients and also in selected children with main renal artery disease. Renal autotransplantation provided excellent results in 25 of 27 patients (92%) who required replacement of all or a major portion of the ureter. Over-all renal function was well preserved in these patients and only 1 has experienced chronic bacteriuria. Renal autotransplantation is a useful alternative to ileal interposition in this setting. Extracorporeal partial nephrectomy and renal autotransplantation were successful in 12 of 14 patients (85%) undergoing a nephron-sparing operation for renal cell carcinoma. In situ techniques are associated with less morbidity and currently are preferred in this group.

Effect of unilateral vesicoureteric reflux on renal growth and the uptake of 99mTc DMSA by the kidney. An experimental study in the minipig

The influence of unilateral vesicoureteric reflux (VUR) on renal growth and the uptake of 99mTc DMSA by the kidney has been investigated in a 2-kidney model in the growing minipig over a period of approximately 5 months. Animals with reflux in association with low voiding pressures and normal bladder function (n = 5), as well as those with raised voiding pressures and abnormal bladder function (n = 7), were investigated with appropriate non-refluxing controls (n = 12). Urinary infection and renal scarring were avoided since these factors may affect kidney function and growth independently. Statistical tests of difference failed to demonstrate any effect of VUR on renal growth or renal uptake of 99mTc DMSA even in the presence of elevated voiding pressures and abnormal detrusor function.

Ureteral replacement using ileum in compromised renal function

Ureteral replacement by ileum is an accepted technique in a highly selective patient population. Two major contraindications in using an ileal ureter are compromised renal function (serum creatinine greater than 2) and a functionally abnormal bladder. We used ileum to bridge a ureteral defect in animals with half of a solitary kidney and low grade azotemia to see if the antirefluxing mechanism of the lower ureter prevented further deterioration in renal function. Twelve female mongrel dogs underwent a right nephrectomy, followed by a left partial nephrectomy six weeks later. Group I (six dogs) had a six cm. segment of ileum interposed between the upper and lower ureteral segments (nonrefluxing). Group II (five dogs) had a ten cm. segment of ileum placed from the upper third of the ureter to the bladder (refluxing). Cystograms, intravenous pyelograms, serum electrolytes, BUN and creatinine were obtained preoperatively, six weeks after the right nephrectomy, one month after left partial nephrectomy and six months after ileal replacement prior to sacrifice. The BUN and creatinine deteriorated in Group II compared to Group I, p = .02 and p = 0.4 respectively (Mann-Whitney test). The BUN and creatinine also deteriorated between one month after left partial nephrectomy and six months after ileal replacement within Group II, p = .07 and p = .14, respectively (Wilcoxon matched-pairs test) but not in Group I. These data suggest that the antirefluxing mechanism of the lower ureter might prevent further deterioration in renal function. We feel that ileum can be used with caution, as an interposition in compromised renal function.

Vesicopyelostomy in the treatment of pelvic kidneys with pelviureteric junction obstruction: long-term follow-up

The surgical management of 6 male patients with pelvic kidneys with pelviureteric junction obstruction is discussed. Two patients presented in advanced renal failure and 1 had peritonitis and septicaemia due to rupture of the renal pelvis. Vesicopyelostomy was preferred to pyeloplasty in 5 patients because of adhesions, multiple aberrant vessels, multiple stones, malrotation and the low pelvic position, but pyeloplasty was done in 1 case. Though vesicoureteric reflux was observed during voiding cystourethrography in all patients, no deleterious effect on the kidney was seen during the 3- to 5-year follow-up period.

Effects of vesicoureteric reflux on renal growth and function as measured by GFR, plasma creatinine and urinary concentrating ability. An experimental study in the minipig

The influence of vesicoureteric reflux (VUR) on renal growth and function measured by glomerular filtration rate (GFR), plasma creatinine concentration and urinary concentrating ability has been examined in a simple one-kidney model in the growing minipig over a period of approximately 5 months. Animals with reflux in association with low voiding pressures and normal bladder function (n = 6), as well as those with raised voiding pressures and abnormal bladder function (n = 5), were investigated together with appropriate non-refluxing controls (n = 12). Urinary infection and renal scarring were avoided since these factors may affect kidney function and growth independently. Statistical tests of difference failed to demonstrate any effect of VUR on 51Cr EDTA GFR or renal growth even in the presence of elevated voiding pressures and abnormal detrusor function. However, a significant association between VUR and reduced urinary concentrating ability was shown.

Long-term results with renal autotransplantation for ureteral replacement

From 1970 to 1984 renal autotransplantation was performed on 23 patients to replace all or a major portion of the ureter. The conditions necessitating ureteral replacement were postoperative ureteral injury in 16 cases, recurrent renal colic in 4, urinary undiversion in 2 and an atonic ureter in 1. Six patients presented with a solitary kidney and 1 underwent staged bilateral autotransplantation. After autotransplantation urinary continuity was restored by ureteroneocystostomy in 11 patients, pyelovesicostomy in 7, ureteroureterostomy in 2, pyeloureterostomy in 2 and ureterosigmoidostomy in 1. Postoperatively, there was no mortality and all but 1 of the autotransplanted kidneys functioned immediately. Two kidneys required removal postoperatively owing to bleeding. Currently, 20 patients are alive with functioning renal autotransplants at intervals of 1.5 to 14 years. The current serum creatinine level in these patients ranges from 1.1 to 2.2 mg. per dl., which in each case is improved or stable compared to the preoperative determination. Only 1 patient has experienced chronic bacteriuria. We conclude that renal autotransplantation provides excellent long-term treatment for patients who require ureteral replacement.

Pyelovesicostomy as a form of urinary reconstruction in renal transplantation

The development of ureteral obstruction or ureteral fistula formation in the renal transplant recipient usually requires surgical repair. This involves reconnecting the donor ureter to either the recipient ureter (ureteroureterostomy) or bladder (ureteroneocystostomy), or creating an anastomosis between the renal pelvis and recipient native ureter (pyeloureterostomy). Occasionally, the donor or recipient ureter is absent, necrotic or diseased so that a ureteroureterostomy, ureteroneocystostomy or pyeloureteral anastomosis cannot be performed. In 8 such cases we have performed a direct anastomosis between the donor renal pelvis and recipient bladder (pyelovesicostomy) with a followup of between 2 months and 11 years. In all 8 patients there has been no deterioration in renal function attributed to obstruction at the anastomotic site or to the free reflux between the bladder and renal pelvis. Because of the excellent short-term and long-term results of pyelovesicostomy, this procedure should be considered as an excellent alternative to pyeloureterostomy, ureteroureterostomy and ureteroneocystostomy in the reconstruction of the upper urinary tract of the renal transplant patient.

Pyelovesicostomy: an alternative to ureteropelvic junction-plasty in pelvic ectopic kidneys

Pyelovesicostomy was performed in 2 cases of hydronephrosis in pelvic kidneys secondary to ureteropelvic junction obstruction. In the first patient, who presented with a solitary kidney, the procedure was done after failure of a dismembered pyeloplasty, while in the second patient the procedure was performed electively. Both patients had sterile urines and stable renal function, although some dilatation persisted in the first case. The indications and the functional aspects of this surgical solution are discussed.

Long-term clinical followup after pyelocystostomy

In March 1971 a 32-year-old man with necrosis of the ureter to a kidney allotransplant underwent anastomosis of the transplant renal pelvis to the bladder. The kidney is functioning normally 9 years later. This surgical technique has been used recently in 3 additional case. Further applications of this procedure are suggested.