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PubMed2005

Stent-related ureteric obstruction in paediatric renal transplantation.

The rates of ureteric obstruction and complications for use of externally draining uretero-vesico-cutaneous (external) stents (Group 1: n=39) and the use of internal uretero-vesical (double-J) stents (Group 2: n=16), in 55 of 64 consecutive paediatric renal-transplant recipients, performed at our institution between January 1996 and December 2003, have been compared. Serum creatinine levels pre and post-operatively and pre and post-stent removal were recorded. The diagnosis of ureteric obstruction was based on an increase in serum creatinine of >or=20%, in conjunction with ultrasound evidence of hydronephrosis or hydroureter, where other causes of renal dysfunction were excluded. Ureteric obstruction occurred in 13 of the 39 patients (33.3%) in Group 1, compared with only one case of ureteric obstruction in the 16 patients (6.25%) in Group 2 (OR=7.5, 95% CI=0.8-70, P=0.038). There was no evidence of a difference in the number of urinary tract infections (9/39 in Group 1, 6/16 in Group 2, OR=0.5, 95% CI=0.14 to 1.8, P=0.275) or the mean length of hospital stay (10.9 days in Group 1, 10.1 days in Group 2, 95% CI=-2.3 to 4 days, P=0.565) between the two groups. Glomerular filtration rate (GFR) improved in the week after stent removal in Group 2, but deteriorated in Group 1 (P=0.07). This non-randomised comparison of stent types supports the use of prophylactic double-J stents in paediatric renal transplantation- in terms of decreased ureteric complications and improved renal function post-stent removal.

Adolescent↗
PubMed1982

Uptake of Pi in brush border vesicles after release of unilateral ureteral obstruction.

After release of complete unilateral ureteral obstruction, a decreased fractional excretion of phosphate (Pi) is observed in the postobstructed kidney compared with the nonobstructed (control) kidney. To determine whether this decrease in the urinary excretion of Pi is due to changes in Na+-dependent Pi transport across the renal brush border membranes of postobstructed and control kidneys, membrane vesicles were prepared from the brush borders of kidneys from dogs that had undergone complete unilateral ureteral obstruction. Alkaline phosphatase activity was decreased in membrane vesicles isolated from postobstructed kidneys. No differences were observed in Na+-dependent Pi transport or in Na+ uptake in membrane vesicles isolated from postobstructed as compared with control kidneys. The in vivo administration of parathyroid hormone decreased Na+-dependent Pi transport in membrane vesicles isolated from postobstructed and control kidneys despite the absence of a phosphaturic response. Our findings suggest that no intrinsic change in the transport characteristics of Pi across the luminal membrane of renal tubular cells occurs with unilateral ureteral obstruction. The findings are consistent with the suggestion that the low fractional excretion of Pi in the postobstructed kidney results from very low filtered loads of Pi on the postobstructed side.

Animals↗
PubMed1977

Ureteral obstruction from prostatic carcinoma: response to endocrine and radiation therapy.

Ureteral obstruction occurred in 10% of the patients treated for prostatic carcinoma and most often was associated with poorly differentiated tumors. The response of ureteral obstruction to different forms of therapy was evaluated. Obstruction diminished in 22 of 25 orchiectomized patients (88%) but in only 1 of 6 patients receiving estrogen or antiandrogen therapy alone (17%). Patients who responded favorably to therapy had a significantly better survival than did non-responders. Patients treated early in the course of ureteral obstruction responded better than those treated late, while neither tumor stage nor grade correlated with response to therapy. Radiation therapy for endocrine-resistant ureteral obstruction was effective in only 2 of 8 cases (25%). The literature on ureteral obstruction from prostatic carcinoma and its treatment is reviewed.

Acid Phosphatase↗
PubMed2003

Is enalapril adequate for the prevention of renal tissue damage caused by unilateral ureteral obstruction and/or hyperoxaluria?

Unilateral ureteral obstruction (UUO) and hyperoxaluria (HOX) can lead to end-stage renal disease with tubulointerstitial fibrosis. We investigated the effects of enalapril (E), an ACE-inhibitor, on rat kidneys with either UUO or HOX. Sham-operated, UUO, HOX, UUO+HOX, UUO+E and HOX+E rats were killed 14 days after UUO and/or HOX was initiated. Rat kidney sections were histologically scored for tissue damage and monocyte/macrophage infiltration was demonstrated with ED1 antibody and measured by computer image analysis software. Serious glomerular and tubulointerstitial damage was found for UUO and HOX, consisting of glomerular basement membrane thickening, tubular dilatation/collapse, tubular basement membrane thickening and the infiltration of mononuclear leucocytes (mainly macrophages). For HOX, calcium oxalate crystals were visible. Neither the scored histological parameters nor monocyte/macrophage infiltration was significantly decreased when E-treated were compared with untreated groups. We conclude that E did not ameliorate the parameters scored in either UUO or HOX. This being contrary to findings by other research groups, we hypothesize that E may be effective only in short-term UUO/HOX, with transforming growth factor, TGF-beta1, formation becoming partly independent of Ang II in late-stage UUO/HOX, or other fibrogenic cytokines than TGF-beta1 becoming predominant.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2002

Changes of renal cortical Na-K ATPase activity, protein, and mRNA expression in ureteral obstruction.

Decreased renal Na-K ATPase activity in ureteral obstruction contributes to tubular sodium reabsorption defect in obstructive nephropathy. The integrated changes on the enzyme activity, protein number, and mRNA level of renal cortical Na-K ATPase, in response to bilateral or unilateral ureteral obstruction (BUO & UUO), were studied in rabbits. Ouabain-sensitive Na-K ATPase activities of renal cortex were significantly decreased at 24 h after BUO and further decreased at 48 h. The unobstructed contra-lateral kidney had significantly higher Na-K ATPase activity compared to the obstructed side. Immunoblots of Na-K ATPase alpha and beta subunits protein were both decreased at 24 h of BUO and further decreased at 48 h. The levels of Na-K ATPase beta subunit mRNA showed to be significantly decreased at 12 h after obstruction and further decreased at 24 and 48 h. However, the levels of alpha subunit mRNA were not changed as that of beta subunit throughout the study period. This study also used a newly developed method for release of obstruction. All the parameters studied above recovered to variable extents after release of the ureteral obstruction. In summary, decreases in Na-K ATPase activity, protein, and mRNA in obstructed kidney are specific cellular responses to ureteral obstruction. The degree of down-regulation is related to the duration of obstruction. The reduced activity of Na-K ATPase can be explained by decreased enzyme protein. However, the discordant findings in Na-K ATPase subunits protein amounts and mRNA changes suggest that renal Na-K ATPase subunits have different cellular regulatory processes to obstruction, in which transcriptional, translational and even intra-cytoplasmic processing may be involved.

Animals↗
PubMedDate not supplied

Ureteral obstruction as a complication of renal transplantation: a review.

Ureteral obstruction in a renal allograft, due to a variety of etiologies, is both a challenging diagnostic and therapeutic disorder. Since ureteral obstruction in a renal transplant recipient usually presents as azotemia, it must also be distinguished from acute rejection. Although ultrasound is non-invasive and readily available, the most definitive diagnostic tool is percutaneous nephrostomy tube placement with antegrade nephrostogram. A variety of therapeutic approaches are available to treat ureteral obstruction in a renal allograft. These procedures can be open (e.g., repeat ureteroneocystotomy) or utilize an endourological approach (e.g., transluminal ureteral dilatation). From an experimental standpoint, recent data in rodent models of experimental hydronephrosis demonstrate similar pathobiologic events in both the obstructed kidney and an allograft undergoing the chronic rejection process. To this end, investigation needs to be conducted to assess whether partial, unrecognized ureteral obstruction in an allograft hastens the development of chronic rejection. This would further underscore the importance of ureteral obstruction as a cause for not only acute azotemia in an allograft, but also chronic deterioration in renal transplant function.

Humans↗
PubMed1996

A case of polyarteritis nodosa with bilateral ureteral obstruction.

We report a case of bilateral ureteral obstruction most likely caused by polyarteritis nodosa. The diagnosis was based upon muscle biopsy which showed typical necrotizing vasculitis in medium size artery in conjunction with microaneurysms in renal angiography. Ureteral obstruction is a rare manifestation of polyarteritis nodosa. This condition is thought to result from vasculitis of periureteral vessels. The patient was managed with prednisolone alone, which resulted in complete resolution of ureteral obstruction on both sides.

Female↗
PubMedDate not supplied

Tubuloglomerular feedback in rats with chronic partial bilateral ureteral obstruction.

UNLABELLED: Rats with chronic partial unilateral ureteral obstruction (UUO) have a paradoxical resetting of the tubuloglomerular feedback (TGF) mechanism. During extracellular fluid volume expansion (VE) in control animals, a decrease in TGF sensitivity is normally noted. In rats with partial UUO, however, TGF sensitivity in the obstructed kidney was increased, associated with a relative reduction in single nephron glomerular filtration rate. In the present study, we examined the tubular and interstitial pressures, whole kidney function and the TGF system in rats with chronic partial bilateral ureteral obstruction. The rats were divided into preferentially ipsilaterally and preferentially contralaterally obstructed, as judged by pelvic volume. Measurements were performed both during hydropenia and during VE. During hydropenia TGF characteristics were the same in the 2 groups. During VE, however, TGF sensitivity was unchanged in the most obstructed kidneys (ipsilateral), while if the obstruction was preferentially contralateral, TGF-sensitivity decreased. This opposite change in TGF sensitivity resulted in higher electrolyte and water excretion from the least obstructed kidney. The change in TGF sensitivity was not correlated to renal interstitial pressure. IN CONCLUSION: rats with moderate chronic partial bilateral ureteral obstruction have an almost preserved function with regard to renal hemodynamics and excretion during hydropenia. During volume expansion, however, different responses were found in the least and most obstructed kidneys, with a decreased sensitivity of TGF in the least obstructed kidney, while TGF sensitivity was unchanged in the most obstructed kidney.

Animals↗
PubMed1992

In situ extracorporeal shock wave lithotripsy for obstructing ureteral stones with acute renal colic.

In situ (no instrumentation) extracorporeal shock wave lithotripsy (ESWL*) was used to treat 49 patients with obstructing ureteral stones causing acute renal colic. Ureteral obstruction was diagnosed on the delayed films of an excretory urogram and was classified as severe (dilatation above and no contrast medium seen below the stone) in 17 patients and partial (dilatation above and contrast medium seen below the stone) in 32. Upper third ureteral stones were present in 41 patients (obstruction severe in 15 and partial in 26) and lower third ureteral stones were present in 8 (obstruction severe in 2 and partial in 6). ESWL was performed within 14 days of the onset of the acute renal colic because of persistent pain with an unmodified Dornier HM3 lithotriptor in 17 patients and a Medstone STS device in 32. With single stones the stone-free rate at 3 months, the repeat ESWL rate and the secondary procedure (stone basketing) rate were 92%, 6% and 8%, respectively, with severe obstruction, and 78%, 6% and 6%, respectively, with partial obstruction. No urinary drainage procedures for sepsis were required after ESWL. Obstructing ureteral stones, which presented mainly in the upper third of the ureter, were successfully treated with in situ ESWL without the need for either bypassing the stone with a ureteral stent or for pushing the stone back into the kidney before treatment with ESWL.

Acute Disease↗
PubMed1987

Percutaneous nephrostomy for palliation of metastatic ureteral obstruction.

Urinary diversion for palliation of metastatic ureteral obstruction has been associated with high rates of morbidity and mortality, especially with open surgical nephrostomies. An evaluation of percutaneous nephrostomy drainage for the palliation of metastatic ureteral obstruction in 27 patients revealed an increase in survival with decreased morbidity, and a follow-up ranging from three to twenty-five months. The mean survival of all patients was 6.63 months (N = 19), with 8 patients still alive. The histology was the main determinant of length of survival, with prostate, rectal, and cervical cancer patients surviving the longest. The perioperative mortality was 11.1 per cent (3/27), and the postoperative complications consisted of hemorrhage requiring transfusion 29.6 per cent (8/27), gastrointestinal bleeding 3.7 per cent (1/27), and dislodged nephrostomy tubes 44.4 per cent (12/27). Percutaneous nephrostomy drainage is a less morbid procedure than open surgical procedures, and the main determinant of length of survival is the histology of the primary tumor in patients with metastatic ureteral obstruction.

Adult↗
PubMed1976

Inner medullary plasma flow in the kidney with ureteral obstruction.

To test the thesis that ureteral obstruction causes medullary ischemia, we determined inner medullary plasma flow (IMPF) in rats with bilateral or unilateral ureteral obstruction, and after relief of obstruction, by the intravenous 125I-albumin infusion technique. A progressive decline in IMPF was observed during obstruction of 18 h duration, greater in bilateral obstruction (7% of normal at 5h) than in unilateral obstruction (28% of normal at 5 h). The elevation in ureteral pressure was greater and more sustained in bilateral obstruction. After relief of obstruction, IMPF rose to 69-78% of normal in both groups within 2 h. Histologic studies showed tubular necrosis in portions of the inner and outer medulla immediately beneath the renal pelvic epithelium after bilateral or unilateral obstruction of 18 h duration, and India ink perfusion studies showed very poor filling of vasa recta in these areas. The concentrating defect in the postobstructive kidney may be related, at least in part, to damage inflicted by medullary ischemia during obstruction.

Albumins↗
PubMed1975

Nature of the acidifying defect after the relief of ureteral obstruction.

Nature of the acidifying defect observed after relief of ureteral obstruction. The acidifying capacity of the normal and experimental kidney was studied in rats three hours after release of complete unilateral ureteral obstruction or after unilateral release of unilateral ureteral obstruction, mean plasma bicarbonate concentration was 23.5 mEq/liter, and plasma pH, 7.45. Urine pH from the postreleased kidney was 7.47 and 6.01 from the control side. Net acid escretion averaged 0.97 muEq/min in the experimental kidney. Fractional excretion of bicarbonate averaged 0.02% in the control and 3.17% in the experimental kidney. In eight animals with unilateral release of bilateral ureteral obstruction, mean plasma bicarbonate was 16.9 mEq/min and plasma pH was7.35. Mean urine pH in the postreleased Kidney was 6.11, net acid excretion averaged 2.01 plus or minus 0.69 muEq/min and fractional bicarbonate excretion averaged 0.84%.

Ammonium Chloride↗
PubMedDate not supplied

Ureteral obstruction after ureteroneocystostomy in dogs assessed by technetium TC 99m diethylenetriamine pentaacetic acid (DTPA) scintigraphy.

OBJECTIVE: To use technetium Tc 99m diethylenetriamine pentaacetic acid (99mTc-DTPA) renal scintigraphy to monitor ureteral obstruction after ureteroneocystostomy in a canine model of partial ureteral obstruction. STUDY DESIGN: Experimental study. ANIMALS: Eight normal adult dogs. METHODS: Partial ureteral obstruction was created in 8 dogs by incomplete ligation of the terminal right ureter. Two weeks later, ureteroneocystostomy was performed in 7 dogs with unilateral partial ureteral obstruction and in 1 dog that had developed bilateral partial ureteral obstruction. 99mTc-DTPA scintigraphy was performed intermittently for 2 weeks after ureteroneocystostomy. Renal transit time of each kidney, as assessed by the time to maximal uptake (time of peak), and glomerular filtration rate, as assessed by percentage of kidney uptake of the radiopharmaceutical between 1 and 3 minutes, were estimated. Comparison between affected and nonaffected kidneys was performed with the Wilcoxon rank sum test. RESULTS: Unilateral partial ureteral obstruction was induced successfully in 7 dogs. In 1 dog, bilateral partial obstruction was induced inadvertently. After ureteroneocystostomy, percentage of kidney uptake of 99mTc-DTPA was low in 4 affected kidneys. The uptake returned to within normal limits in 2 of the kidneys during the observation period. The time activity curve had a more rounded appearance or was increasing continuously for all affected kidneys. A significant increase in renal transit time was observed 2 and 4 days after ureteroneocystostomy. Transit time progressively returned to normal by 4 to 11 days for all affected kidneys except 1. CONCLUSION: Ureteroneocystostomy resulted in persistent partial ureteral obstruction for 4 to 11 days as determined by 99mTc-DTPA scintigraphy. CLINICAL RELEVANCE: 99mTc-DTPA scintigraphy may be a useful procedure for monitoring renal function and ureteral obstruction after ureteroneocystostomy. Persistent partial ureteral obstruction may be seen 1 to 2 weeks after ureteral reimplantation in dogs with previously existing dilated ureters.

Animals↗
PubMed1994

Prognostic significance of ureteral obstruction in primary cervical cancer.

OBJECTIVES: To evaluate the prognostic significance of ureteral obstruction in women with cervical cancer and the result of aggressive urinary diversion. METHODS: The clinical history and X-rays of 52 women with Stage III and IV cervical cancer seen at Vanderbilt University between 1981 and 1991 were retrospectively reviewed. RESULTS: Twenty-nine (55.8%) of these patients had unilateral [15] or bilateral [14] ureteral obstruction. There was no statistically significant difference in the survival of patients whether or not ureteral obstruction was present. Ten of fourteen women with bilateral ureteral obstruction and 4 of the 15 patients with unilateral obstruction underwent urinary diversion by percutaneous nephrostomy [9] or retrograde ureteral catheterization [5]. Complications were few. Although patients who underwent urinary diversion had somewhat better survival, it was not statistically significant. CONCLUSIONS: Some patients with ureteral obstruction due to advanced cervical cancer can be salvaged by prompt, aggressive urinary diversion, but large trials are needed to validate this approach.

Adult↗
PubMed1990

The possible involvement of calcium in renal proximal tubular reabsorptive defect in the rat after release of ureteral obstruction.

The temporal relationship between changes in cytosolic free calcium and proximal tubular function was examined in rats following 24 h of unilateral and bilateral ureteral obstruction. Immediately after release of unilateral ureteral obstruction, proximal tubular functions were found to be normal. Cytosolic free calcium in isolated proximal tubules of the ureteral obstructed and contralateral kidneys were 160 +/- 8 and 172 +/- 15 nM, respectively. On the 7th day after release, cytosolic free calcium was not different from the sham control value (135 +/- 6 vs. 149 +/- 7 nM). In contrast, immediately after release of bilateral ureteral obstruction, cytosolic free calcium was increased significantly to 219 +/- 6 from 139 +/- 9 nM in sham-operated controls. Subsequent declines in cytosolic free calcium to 196 +/- 15 and 148 +/- 7 nM were observed at 3 and 7 days after release of bilateral ureteral obstruction, respectively. Over this period, renal tubular functions gradually returned to normal. Changes in cytosolic free calcium correlate well with the reported improvement in renal tubular function after release of bilateral ureteral obstruction. Therefore, one possible mechanism for the impairment of tubular function observed in bilateral ureteral obstruction may be an increase in cytosolic free calcium.

Animals↗
PubMed1994

[A case of inflammatory abdominal aortic aneurysm with associated inferior vena caval and bilateral ureteral obstruction].

One year ago, a 48-year-old man complained of dyspnea, and was diagnosed as mitral valve regurgitation and aortic dissection. He underwent mitral valve replacement and aortic arch grafting. He was also pointed out to have an inflammatory aortic aneurysm (IAAA) in the infrarenal abdominal aorta, but did not undergo surgery. At this admission, he had lumbago and low grade fever probably due to deterioration of the IAAA. On the preoperative radionuclide studies, inferior vena caval obstruction and bilateral ureteral obstruction or severe stenosis were demonstrated by 99mTc-MAA venography and 123I-OIH renogram, respectively. 67Ga scan showed faint abnormal accumulation at the IAAA. He underwent surgery. IAAA had a thick wall in white and hard fibrotic tissue adhered closely to duodenum, jejunum, inferior vena cava and bilateral ureters. After surgery, his renal function was improved. In this case, radionuclide studies were useful for detecting the inferior vena caval obstruction, assessing renal function and inflammatory activity.

Aneurysm, Infected↗
PubMed1984

Contralateral renal hyperplasia and increased renal function after relief of chronic unilateral ureteral obstruction.

Following relief of 1, 2 or 3 weeks of unilateral ureteral obstruction, contralateral compensatory renal growth and increased renal function were measured 3 and 6 months later. Compensatory growth occurred predominantly by hyperplasia, demonstrated by a significant increase in DNA content and a decrease in the RNA:DNA ratio (p less than 0.04). This is in contrast to compensatory growth following nephrectomy or unrelieved unilateral ureteral obstruction, which occurred primarily by hypertrophy with no significant change in DNA content but a significant increase in RNA content and the RNA:DNA ratio (p less than 0.04). Contralateral renal function in animals with relieved unilateral ureteral obstruction was greater than in controls with 2 normal kidneys (p less than 0.05). The contralateral increase in renal function was greater than that in animals subjected to ipsilateral nephrectomy or unrelieved ureteral obstruction, but this did not reach statistical significance. Thus, when growth occurred by hyperplasia, there was a trend to greater increases in renal function than when growth occurred by hypertrophy. Contralateral compensatory renal hyperplasia and increased renal function occurred in conjunction with a decrease in renal mass and function of the ipsilateral post-obstructed kidney. These experiments suggest that the post-obstructed, poorly functioning kidney stimulates contralateral hyperplastic growth and increased renal function. This hyperplastic response is different from the hypertrophic response following nephrectomy or unrelieved unilateral ureteral obstruction, implicating the post-obstructed kidney as the stimulus of the hyperplastic response.

Animals↗
PubMed1989

Renal candidiasis in the rat: effects of ureteral obstruction and diabetes.

The effect of ureteral obstruction on the course of renal candidiasis in a rat model was studied, using both normal and diabetic Sprague-Dawley rats, and a clinical isolate of Candida albicans. Diabetes was induced by streptozotocin injection 1 week prior to inoculation and transabdominal ligation of the left ureter. On day 9 post inoculation, mean titers of Candida were similar in right and left kidneys of obstructed rats. Mean left renal titers for obstructed and control rats were similar (log10 2.68 CFU/g +/- 0.73 (SE) vs. log10 2.21 +/- 0.09, P greater than 0.01). Diabetes produced higher renal titers of Candida, regardless of the presence of ureteral obstruction (log10 5.74 CFU/g +/- 0.57 (SE) vs. log10 2.21 +/- 0.09, P less than 0.01). Animals treated for one week with amphotericin B showed a marked difference in Candida titers between obstructed and control animals (log10 4.14 CFU/g +/- 0.45 (SE) vs. 1.57 +/- 0.38) for both kidneys, and between obstructed and nonobstructed kidneys in the same animals.

Amphotericin B↗