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Ureteral obstruction is a common problem facing the urologist. Tumors, either primary in the urinary tract or metastases from other organs, may be the causal agent. Herein we present the first case reported of ureteral obstruction caused by metastases from adenocarcinoma of the gallbladder.
Ureteric obstruction is rarely encountered in abdominal aortic aneurysms and is due to perianeurysmal fibrosis. 3 cases are described in which aortic aneurysm and retroperitoneal fibrosis are found. Excision of the aneurysm and ureterolysis with intraperitonization of the ureter is the most appropriate surgical procedure but treatment must be individualized according to the patient's condition and the operative discoveries.
Ureteral obstruction occurring five years or more after renal transplantation is uncommon and may mimic allograft rejection. In 2 patients who had received cadaveric renal allograft, ureteral obstruction was detected six and one-half and five and one-half years after transplantation. In both patients, surgery was needed to restore normal renal function and to prevent further renal damage. Excretory urography is important in the follow-up of patients who have undergone renal transplantation, and conditions such as ureteral obstruction should be ruled out before antirejection treatment is started.
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%.
Two cases of spontaneous extravasation of urine in chronic ureteric obstruction are presented. In 1 case the long-standing partial ureteric obstruction was caused by enlarged lymphomatous glands, and extravasation was followed by a perinephric abscess. In the second case, believed to be unique, there was a moderate chronic ureteric obstruction post irradiation, and extravasation was induced by a sudden rise in intra-abdominal pressure due to vomiting.
Three cases of ureteral obstruction associated with aortoiliac aneurysms were studied with computed tomography. CT was able to document the presence of aneurysm and display the perianeurysmal, fibrotic, contrast-enhancing mass accounting for ureteral obstruction. The value of computed tomography in the diagnosis and evaluation of these cases is described.
In 50 consecutive renal allograft recipients, operated upon between September 1975 and March 1977, we have encountered 10 cases of ureteric obstruction. The patients fell into two groups: those with ureteric obstruction of early onset due to intraluminal blood clot, oedema of the distal end of the ureter, ureteric tip necrosis or extrinsic compression by the spermatic cord, and those with obstruction of late onset due to ureteric fibrosis. Two cases of ureteric obstruction due to oedema and 1 due to intraluminal blood clot resolved spontaneously. Transurethral ureteric meatotomy, a recommended procedure for the relief of ureteric obstruction in suitable cases, was successful in 1 of our patients. The remaining 6 patients required open surgical procedures for relief of obstruction. In no instance did ureteric obstruction result in death or graft failure.
The kinetics for mesangial uptake and transport of radiolabeled aggregated human immunoglobulin (Ig)G (AHIgG(125)I) deviated markedly from normal in male Sprague-Dawley rats with ureteral obstruction. Four experimental groups, each containing 25 rats, were used: (a) bilateral ureteral ligation (BUL) with release of one ureter 24 h later; (b) unilateral ureteral ligation with release 24 h later [UUL(R)]; (c) unilateral ureteral ligation without release (unreleased) [UUL(U)]; (d) uremia-control, which consisted of rats with ligated left ureter and a severed right ureter. A similar number of sham-operated rats served as control for each group. AHIgG(125)I (45 mg/100 g body wt) was given intravenously 1 h after release of the ureteral obstruction (25 h after ureteral obstruction or sham surgery). Groups of five control and five experimental animals were sacrificed at 2, 4, 8, 16, and 24 h after injection. At all time intervals, concentrations of AHIgG(125)I in isolated glomeruli from control animals were similar to values obtained from nonobstructed kidneys of UUL(U) and UUL(R) rats: a linear decrease in concentration over a period of 24 h was observed when the logarithm of glomerular AHIgG(125)I concentration was plotted against time. Aberrations in the kinetics were apparent in obstructed kidneys but not in liver, spleen, or blood concentrations of AHIgG(125)I: (a) At 2 h in all obstructed kidneys, glomerular concentration of AHIgG(125)I was markedly reduced. (b) In BUL (released or unreleased), glomerular concentrations of AHIgG(125)I from 4 to 16 h were congruent with 10-fold those in UUL(U) or UUL(R) kidneys. (c) The significant decline in glomerular concentration between 4 and 16 h in control and nonobstructed kidneys was not observed in UUL(R), UUL(U), or BUL (released or unreleased) kidneys; in all obstructed kidneys, a plateau in glomerular concentrations of AHIgG(125)I was observed between 4 and 16 h. (d) After 16 h at a time when the blood level of AHIgG(125)I had decreased to 3% of initial values, there was progressive fall in glomerular AHIgG(125)I. Similar results were obtained in the uremia-control group in rats, which indicated that uremia per se had no measurable effect on mesangial kinetics. These studies demonstrate that ureteral occlusion induces alterations in mesangial uptake (afferent limb) and egress (efferent limb) of macromolecules. Particularly evident is the "blockade" of the efferent limb which is demonstrable at high blood levels of AHIgG(125)I. These alterations in the transit of macromolecules through the mesangium may be mediated in part by the hemodynamic changes that accompany ureteral obstruction.
Micropuncture studies were performed in Munich-Wistar rats with surgically created chronic partial unilateral ureteral obstruction (UUO). Mean values for superficial single nephron (SN)GFR, total GFR, and initial glomerular plasma flow rate (QA) in obstructed kidneys were essentially identical to values in nonobstructed kidneys. Nevertheless, glomerular capillary hydraulic pressure (PGC) was significantly higher in obstructed than in nonobstructed kidneys. This increase in PGC served to offset the markedly reduced glomerular capillary ultrafiltration coefficient that was also confined to the kidneys ipsilateral to the ureteral obstruction. During infusion of indomethacin or meclofenamate, SNGFR and QA decreased significantly, in association with elevations in arteriolar resistances in obstructed kidneys, whereas such changes were not observed in nonobstructed kidneys. The results suggest that local intrarenal factors, rather than circulating or systemic factor(s), bring about functional adaptations to partial ureteral obstruction. In particular, an indomethacin- and meclofenamate-sensitive vasodilator (presumably prostaglandin) plays a role in antagonizing the effects of a simultaneously acting vasoconstrictor which, although not identified, displayed the functional properties of angiotensin II.
In 43 patients with equivocal pelvi-ureteric obstruction, conventional urography was supplemented with diuresis urography. After peroral hydration with 0.5 liters fluid, a large volume of urographic contrast medium was administered and increased diuresis provoked by intravenous injection of furosemide. A relative obstruction of flow was then accentuated by increased dilatation of the renal pelvis. The technique deserves a wider use in the radiologic investigation of patients with equivocal obstruction at the pelvi-ureteric junction.
5 cases of ureteric obstruction occurring in renal allotransplant recipients who had received their grafts more than 3 years prior to presentation are reviewed.
Carcinoma metastatic to the ureter is uncommon, only 160 patients having been reported upon to date. During a ten year period, 82 patients with ureteral obstruction, secondary to metastatic disease, were seen at the UCLA Hospital. A critical analysis of the records of these patients revealed important clinical and diagnostic criteria to aid in the evaluation and treatment of extrinsic ureteral obstruction. Tumors of the cervix, prostate, breast and colon-rectum were the most common primary lesions to metastasize to the ureter. Subtle changes in urinary symptoms or in laboratory values should alert the physician to the possibility of ureteral involvement. Early detection of metastatic ureteral obstruction prior to the ravages of uremia may allow time for more aggressive use of adjuvant therapeutic modalities that would, at a later stage of the disease, be ineffectual or contraindicated.
Prostaglandins (PGs) E2 and F2 alpha in the rabbit kidney were determined by radioimmunoassay to study the effects of unilateral ureteral obstruction on intrarenal PGs. An increase of PGE2 in the inner medulla was observed in the hydronephrotic kidney. When isotonic glucose solution was infused after the release of ureteral obstruction, an elevation of PGE2 in the outer medulla occurred in the hydronephrotic kidney. Under water diuresis immediately following the release of obstruction, PGE2 in the inner medulla showed significant correlations to urinary flow rate, urinary osmolar concentration and free water clearance. The present study indicates that PGE2 in the inner medulla is enhanced by ureteral obstruction and may have a close relation to renal functional damage in mild hydronephrosis.
In 285 renal transplantations, performed during the years 1967-1978, 6 ureteral obstructions (2,1%) and 15 urinary fistulas (5,3%) were observed. Ureteral obstructions occurred in the late phase after transplantation and were caused by strictures at the uretero-vesical anastomosis (two patients), compression of the ureter by enlarged kidney during rejection (one patient) resp. lymphocele (one patient) and strictures at the pyelo-ureteral junction (two patients). Satisfactory results were achieved by surgical treatment in all patients. Urinary fistulas occurred in the early postoperative phase. Two vesical, 12 vesico-ureteral and one calyceal fistula were observed. 7 fistulas (1 vesical, 6 vesico-ureteral) closed spontaneously after temporary drainage of the bladder. 8 fistulas were repaired surgically. While satisfactory results were obtained in 13 patients, two patients died due to infection and sepsis after reoccurrence of fistulas.
A canine model of bilateral chronic partial ureteral obstruction with one side severely obstructed and the other side moderately obstructed was used to determine which kidney should be released initially to facilitate maximum recovery of renal function. The data show a significantly greater return of total renal function (20%) if the more severely injured kidney is released first.
A canine model of bilateral chronic partial ureteral obstruction with one side severely obstructed and the other moderately obstructed was used to determine which kidney should be initially released to facilitate maximum recovery of renal function. The data show a significantly greater return of total renal function (20 per cent) if the more severely injured kidney is released first.
The effect of 24 h of unilateral ureteral obstruction on HCO3 reabsroption and urinary acidification was studied in dogs. The postobstructed kidney (EK) had a significantly lower glomerular filtration rate and renal plasma flow than the contralateral kidney (CK). Urinary pH prior to HCO3 loading was significantly higher in the EK as was maximal HCO3 reabsorption. Saline loading depressed HCO3 reabsorption to the same degree in both kidneys. Urinary PCO2, during HCO3 loading, and during phosphate infusion, was significantly lower in the EK than the CK. Fractional Na excretion was significantly higher in the EK than the CK after deoxycorticosterone acetate administration. Na2SO4 administration enhanced acid excretion only in the CK. K excretion was significantly lower in the EK than the CK both during HCO3 loading and Na2SO4 administration. There was redistribution of cortical blood flow from the outer cortex toward the inner cortex in the EK as compared to the CK. There was no difference in plasma renin activity from both renal veins. These data demonstrate enhanced proximal H+ secretion (which is abolished by volume expansion) and impaired distal H+ secretion by the postobstructed kidney. The distal defect is likely an effect of a generalized disorder of distal transport in that both K secretion and steroid-responsive Na reabsorption were impaired in the postobstructed kidney.
During a 4-year-period, 5 cases of ureteral obstruction by aorto-iliac aneurysm were detected. Over the same period 50 aorto-iliac aneurysms were resected. One of the 5 patients was not operated on. In the remaining 4, the aneurysm was resected and replaced by a Dacron bifurcation graft. Nephrectomy was performed in the first 2 patients. Autotransplantation of the remaining kidney was carried out in one case following enucleation of a hypernephroma ex vivo. In the other 2 patients, ureterolysis and intraperitoneal transposition of the ureter was performed in conjunction with resection of the aneurysm. One of the latter patients suffered from uraemia due to a non-functioning kidney on the other side. Ureteral obstruction appears to be a relatively common complication of aorto-iliac aneurysm. Elective evaluation of patients with aortic aneurysms should include late aortograms visualizing the ureters.