Ultrasonographic diagnosis of a lymphomatous lymph node presumptively infiltrating the ureter causing hydronephrosis in a 3-year-old dog

A 3-year-old male neutered mixed breed dog was presented for chronic vomiting and diarrhea. Abdominal ultrasound revealed a large amorphous, heterogeneous mass within the left mid to caudal abdomen most consistent with medial iliac lymph node. It appeared to invade the left ureter and extend distally causing ureteral obstruction and hydronephrosis. Concurrent additional ultrasound findings were consistent with metastatic or multicentric neoplasia. Fine needle aspirates of the lymph node and spleen both confirmed large cell lymphoma. These findings present evidence of lymphoma invading directly from an organ into the ureter which has not previously been reported in dogs.

Ureteroneocystostomy for treatment of struvite urolithiasis in a ferret

OBJECTIVE

To assess the clinical outcome of a ferret undergoing a ureteroneocystostomy for treatment of urolithiasis.

ANIMAL

A 10-month-old spayed female ferret.

CLINICAL PRESENTATION, PROGRESSION, AND PROCEDURES

The ferret was evaluated for straining to urinate and defecate, hematochezia, and a rectal prolapse. Plain radiographs revealed large cystic and ureteral calculi. Clinicopathologic analyses indicated the ferret was anemic with an elevated creatinine concentration. Exploratory laparotomy defined bilateral ureteral calculi that were unable to be successfully moved into the bladder. A cystotomy was performed to remove a large cystic calculus. Serial abdominal ultrasonographic examinations showed progressive hydronephrosis of the left kidney and persistent pyelectasia of the right kidney secondary to bilateral ureteral calculi. This confirmed a left ureteral obstruction secondary to the distal calculus while the right ureter remained patent.

TREATMENT AND OUTCOME

A ureteroneocystostomy was performed to allow for left renal decompression. The ferret recovered well despite worsening hydronephrosis of the left kidney in the perioperative period. The ferret was discharged from the hospital 10 days after initial evaluation. At 3-week follow-up, abdominal ultrasonography confirmed resolution of hydronephrosis and ureteral dilation of the left kidney and ureter.

CLINICAL RELEVANCE

A ureteroneocystostomy successfully allowed renal decompression and ureteral patency in a ferret with urolithiasis. To the authors' knowledge, this is the first time this procedure has been reported in a ferret for treatment of a ureteral calculus obstruction and may result in good long-term outcome.

Surgical treatment of retroiliac ectopic ureters with secondary hydronephrosis and hydroureter in a dog

CASE DESCRIPTION

An 8-month-old 41.2-kg (90.6-lb) sexually intact male Dogue de Bordeaux with urinary incontinence and signs of nausea was referred for further evaluation and treatment of bilateral hydronephrosis, hydroureter, and ectopic ureters.

CLINICAL FINDINGS

Clinicopathologic analyses revealed urine specific gravity and serum concentrations of urea nitrogen and creatinine within reference limits. Abdominal ultrasonography and CT revealed unilateral abdominal cryptorchidism, ureters that bilaterally passed dorsal to and appeared compressed by the external iliac arteries (retroiliac ureters), and bilateral hydronephrosis, hydroureter, and ectopic ureters. On CT, minimal uptake of contrast medium by the right kidney indicated either a lack of renal function or ureteral obstruction.

TREATMENT AND OUTCOME

The dog underwent exploratory laparotomy, right ureteronephrectomy, left neoureterocystostomy, bilateral castration, and incisional gastropexy without complication and was discharged 2 days postoperatively. Eleven days after surgery, the dog had improved but continued urinary incontinence, improved left hydronephrosis and hydroureter, and serum concentrations of urea nitrogen and creatinine within reference limits. At 24 months after surgery, the dog was reportedly clinically normal, other than having persistent urinary incontinence.

CLINICAL RELEVANCE

To our knowledge, this was the first report of a dog with retroiliac ureters and compression-induced ureteral obstruction with secondary hydroureter and hydronephrosis. Retroiliac ureters should be considered as a differential diagnosis in young dogs with ureteral obstruction. Our findings indicated that a good outcome was possible for a dog with retroiliac ureters treated surgically; however, the presence of additional congenital anomalies should be considered and may alter the prognosis in dogs with retroiliac ureters.

Hydronephrosis in a dairy calf: A diagnosis delayed by a clinician's Bayesian brain reasoning

A 3-week-old female dairy calf was presented because of severe weakness and diarrhea. Physical examination and ultrasound findings lead to a tentative diagnosis of intestinal obstruction, although serum biochemistry suggested a primary renal disorder. Reassessment of ultrasound images allowed diagnosis of hydronephrosis that had been misdiagnosed probably because of the clinician's biased Bayesian reasoning. Pyelonephritis without renal failure was diagnosed 2.5 months later. The calf was euthanized and the diagnoses were confirmed.

Resolution of nonurine transudative pleural effusion in a cat after removal of a hydronephrotic kidney

CASE DESCRIPTION A 3-year-old spayed female Bengal cat was evaluated because of a history of bilateral pleural effusion and hydronephrosis of the right kidney. CLINICAL FINDINGS Cytologic analysis of a pleural fluid sample revealed characteristics of a pure transudate with a high percentage of lymphocytes. Results of fluid biochemical testing were not consistent with urine or chyle. Serum biochemical analysis and echocardiography yielded no evidence of hypoalbuminemia or high hydrostatic pressure secondary to cardiac disease. Abdominal ultrasonography revealed hydronephrosis of the right kidney and hydroureter of the right ureter. TREATMENT AND OUTCOME Exploratory laparotomy with nephrectomy of the right kidney was performed. At the time of surgery, there was no evidence of communication between the retroperitoneal space and thoracic cavity. No other treatments were performed. No evidence of pleural fluid accumulation was detected 1 week after surgery, and no recurrence of clinical signs associated with pleural effusion was observed for > 1 year after surgery. CLINICAL RELEVANCE Transudative, or nonchylous lymphatic, pleural effusion secondary to intra-abdominal disease, but independent of a low plasma protein concentration, is uncommon in veterinary medicine. This case emphasized that urinary tract obstruction should be considered as a differential diagnosis for cats with pleural effusion when more common disorders are not identified. Even without evidence of direct communication between the abnormal kidney or retroperitoneal space and the pleural space, removal of the hydronephrotic kidney appeared curative.

Surgical management of vesicoureteral reflux with recurrent urinary tract infection after renal transplantation in a dog

CASE DESCRIPTION A 3-year-old male Cocker Spaniel renal transplant recipient was readmitted 39 weeks after transplantation because of acute clinical signs of pollakiuria, intermittent vomiting, decreased appetite, lethargy, and mild fever. CLINICAL FINDINGS Hydronephrosis and hydroureter were observed with ultrasonography and contrast cystography, and a diagnosis of vesicoureteral reflux (VUR) was made. Urinary tract infection (UTI) caused by Escherichia coli was also diagnosed on the basis of results of urine culture. TREATMENT AND OUTCOME Despite treatment of the UTI with an appropriate antimicrobial for 6 weeks, the VUR persisted and the UTI recurred 9 weeks after cessation of antimicrobial treatment. Therefore, surgical correction by means of revision extravesicular ureteroneocytostomy was performed. Both VUR and hydronephrosis resolved after surgery. No recurrences of clinical signs of urinary tract complications were observed during the subsequent 22-month follow-up period. CLINICAL RELEVANCE Results suggested that ureteral reimplantation with an extravesicular technique incorporating a long submucosal tunnel may be an effective treatment for VUR when medical management fails in canine renal transplant recipients with recurrent UTIs.

Bilateral congenital ureteral strictures in a young cat

An 8-month-old cat was presented with bilateral hydronephrosis. Bilateral ureteral obstructions were identified by diagnostic imaging and confirmed by necropsy. Histopathologic findings revealed polypoid transitional epithelial hyperplasia with chronic lymphoplasmacytic inflammation. This report documents congenital ureteral strictures as a cause of ureteral obstruction in a young cat.

Ultrasound-guided percutaneous antegrade hydropropulsion to relieve ureteral obstruction in a pet guinea pig (Cavia porcellus)

Severe hydroureter and hydronephrosis secondary to ureteral obstruction by calculus were present in a guinea pig. A palliative ultrasound-guided percutaneous antegrade hydropropulsion was performed under general anesthesia to relieve the ureteral obstruction and the associated clinical signs. We describe the technique and the considerations for its potential application in similar cases.

Obstructive uropathy secondary to uterine leiomyoma in a chimpanzee (Pan troglodytes)

Complications due to uterine leiomyomata in chimpanzees have rarely been documented. Here we describe a female chimpanzee that developed severe hydronephrosis in the right kidney due to leiomyoma. Because hysterectomy did not alleviate the hydronephrosis, nephrectomy was elected. After these procedures, the chimpanzee is doing well. Leiomyomata screening programs with treatment algorithms are a useful component of a comprehensive chimpanzee program.

Ultrasound-guided percutaneous antegrade pyelography with computed tomography for the diagnosis of spontaneous partial ureteral rupture in a dog

A 10-year-old spayed female dalmatian dog developed acute vomiting and abdominal pain. Ultrasound examination of the abdomen showed right hydronephrosis and proximal ureter dilation with mild retroperitoneal free fluid. Computed tomography (CT) of the abdomen confirmed the ultrasonographic findings and revealed, additionally, a right ureteral stone. Spontaneus rupture of the right ureter was confirmed with CT post ultrasound-guided percutaneous antegrade pyelography. Pyeloureteral rupture and the presence of a ureteral stone were confirmed at surgery.

Obstructive urolithiasis, unilateral hydronephrosis, and probable nephrolithiasis in a 12-year-old Clydesdale gelding

A 12-year-old Clydesdale gelding was presented for colic and dysuria. Obstructive urolithiasis and chronic renal disease were diagnosed via transurethral endoscopy and percutaneous ultrasonography. Nephroliths, hydronephrosis, and peri-ureteral fibrosis were present. Surgical intervention was declined and the gelding was managed medically with antibiotics and dietary modification.

Unilateral nephrectomy for hydronephrosis in a pet rabbit

A young rabbit was diagnosed with unilateral hydronephrosis. The affected kidney was surgically removed. Nearly 3 years after the nephrectomy, the rabbit is doing well. The diagnosis, surgery, and pathophysiology of unilateral renal obstruction are discussed in this article.

Proximal ureteral ectopia causing hydronephrosis in a kitten

A 2-month-old, female cat was presented for abdomen dilation. The patient was undernourished, and severe left hydronephrosis was diagnosed after clinical, ultrasonographical and radiographical examination. Although pyelography was performed in order to visualise the ureteral course, surgery was necessary to reach a final aetiological diagnosis and treatment. At gross examination, the left ureter crossed the renal capsula at the level of the caudal renal pole, and the subcapsular ureteral segment was markedly dilated. Distal to the renal capsula, the left ureter was very thin when compared to the right. The parenchyma of the left kidney, as suggested by ultrasonographical evaluation, was extremely reduced in thickness. An ureteronephrectomy was performed. Histopathological evaluation revealed glomerular sclerosis and diffuse parenchymal fibrosis. Severe hydronephrosis derived from an altered renal pelvic anatomy and abnormal ureteral course determining functional stenosis. Diagnosis of congenital anomaly before development of complications such as hydronephrosis could have allowed a surgical renal capsulectomy and obstruction relief. To the author's knowledge, this is the first report of severe hydronephrosis associated to altered renal pelvic anatomy and proximal ureteral ectopia in cat.

Unilateral perinephric pseudocyst secondary to hydronephrosis in a C57BL/6J mouse

A 9-month-old C57BL/6J mouse had progressive abdominal distension over a 1-week period, and a distended left renal capsule was discovered at postmortem examination. Incision of the capsule showed a tan, cloudy fluid that separated the renal capsule and the remnant left kidney. Microscopically, the capsule was significantly separated from the renal parenchyma by clear space and necrotic cellular debris. The majority of the lining of the renal capsule was composed of fibrous connective tissue and lacked an epithelial lining, consistent with a subcapsular perinephric pseudocyst. In addition, attached to intermittent portions of the renal capsule were thin rims of compressed cortical tissue lined by transitional epithelium. The finding of remnant cortical tissue lined by transitional epithelium is consistent with severe hydronephrosis and indicates that the hydronephrosis preceded the formation of the perinephric pseudocyst. To our knowledge, this is the first case report to characterize a perinephric pseudocyst secondary to severe hydronephrosis in a mouse.

Congenital ectopic ureters in a continent male dog and cat

A male dog and cat were evaluated because of clinical signs associated with hydronephrosis. Both animals had ectopic ureters, but neither had urinary incontinence. The diagnoses were made by use of ultrasonography, excretory urography, retrograde urethrocystography, and surgery. In both animals, hydronephrosis was bilateral but of unequal severity, such that unilateral ureteronephrectomy could be performed. Both animals underwent ureteroneocystostomy of the remaining ureter. This treatment resulted in good clinical outcome during follow-up periods of 18 months and 3 years.

[B-mode and color Doppler sonography of kidneys in healthy lambs and lambs with urolithiasis]

The objectives of this study were to determine some morphological characteristics of kidneys and resistive index (RI) changes in renal interlobar artery using B-Mode and color coded doppler sonography in lambs with urolithiasis. The study was performed in 14 male lambs (8 patients, 6 healthy) aged between 2-2.5 months in the same herd. The kidneys had a mean length of 55.6 +/- 1.6 mm, a width of 31.8 +/- 1.2 mm and a parenchymal width of 10.6 +/- 0.6 mm in healthy lambs. These values were 95.4 +/- 3.6., 52.4 +/- 1.3 and 8.75 +/- 0.5 mm, respectively in lambs with urolithiasis. These differences between both groups were significant. Furthermore, the mean resistive index values in lambs with urolithiasis (0.81 +/- 0.017 m/sn) were significantly higher than controls (0.62 +/- 0.013 m/sn). It was concluded that B-Mode and color coded doppler sonography might provide useful information for detection of changes in kidneys of lambs with urolithiasis like hydronephrosis and renal swelling as well as elevated resistance in the renal interlobar artery.

Percutaneous ultrasound-guided pyelography aided diagnosis of ectopic ureter and hydronephrosis in a 3-week-old filly

Ultrasound-guided percutaneous pyelography has previously been used in dogs to diagnose ectopic ureter. To the authors' knowledge its use has never been reported in the horse. This paper reports the technique used in a three-week-old filly with a suspected ectopic ureter. Pyelography can be performed under sedation and is a relatively simple, safe procedure. The technique enables assessment of individual renal function through collection and analysis of urine from each renal pelvis.

Microvasculature of hydronephrotic kidneys in KK-A(Y) mice

Spontaneous hydronephrosis in KK-A(Y) mice was studied using light and electron microscopy and scanning electron microscopy of resin casts to evaluate micro vascular changes in the kidney. The renal parenchyma was extremely thin as a result of tubular atrophy. Histologically, varying degrees of glomerulosclerosis were observed. Ultrastructurally, marked thickenings of the glomerular basal lamina, an increase in mesangial cells and matrix, and marked effacement of foot processes were observed. In resin casts, a marked reduction in number of glomeruli was evident. The capillaries were thin, strangulated and tom-off to varying degrees in severely affected glomeruli. In the medulla, the three-dimensional capillary network running along the tubules was lost and changed to a two-dimensional vascular bed. Despite severe hydronephrosis, the glomerular capillary network was relatively well preserved, being either slightly or moderately injured in approximately 60% of surviving glomeruli.

Congenital bilateral ureteral stenosis and hydronephrosis in a neonatal puppy

Three days after an uneventful parturition, a Brittany spaniel/beagle puppy (Canis familiaris) was nursing but not gaining weight as rapidly as were its littermates. Although its diet was supplemented, the puppy died 10 days after birth. The renal pelves were enlarged and filled with urine. Both ureters were thin throughout their length, and urine could not be expressed from either kidney into its respective ureter. The bladder contained no urine and was firmly embedded in the umbilicus. Histologically, both kidneys were hydronephrotic and contained hypoplastic collecting tubules. The diameter of the right (0.55 mm) and left (0.57 mm) ureters at the uteropelvic junction were narrower than those of an age-matched control of the same breed (1.03 mm and 1.02 mm) and were lined by hypoplastic urothelium. Trichrome staining of the ureters revealed excessive collagen and disorganized smooth muscle fibers; in contrast, the control had predominantly circular smooth muscle fibers and less fibrous tissue. Although neither blood nor aqueous humor could be evaluated for urea nitrogen, we suspect that the puppy died from uremia. The congenital bilateral ureteral stenosis and hydronephrosis of the described puppy is similar to a form of uteropelvic obstruction in humans.

Congenital cystic disease of the liver and kidney in a pygmy goat

A 1-month-old pygmy goat was presented with abdominal distension and hematuria. Anemia, leukocytosis, and increased bilirubin and blood urea nitrogen levels suggested renal and hepatic disease. Radiographs revealed bilateral renomegaly, and ultrasound confirmed bilateral hydronephrosis. Necropsy findings determined that the renomegaly was due in part to edema and marked cystic tubular distension. Similarly, intrahepatic bile ducts were ectatic. The character and distribution of the gross and histologic lesions were consistent with a polycystic disorder, presumably congenital, affecting the liver and the kidney.

Use of 99mTc-mercaptoacetyltriglycine to evaluate renal function in horses

Ten healthy horses were injected intravenously with 99mTc-MAG3 and the disappearance of radioactivity from the blood was measured. The total body clearance (Cl(B)) and elimination half-life (t1/2(beta)) were 7.9 +/- 1.5 ml/kg/minute and 32.8 +/- 4.1 minutes, respectively. The disappearance of 99mTc-MAG3 from the blood of 2 horses with compromised renal function was also measured. The data suggest that 99mTc-MAG3 is a useful and clinically applicable radiopharmaceutical for measurement of effective renal blood flow in the horse.

Hydronephrosis and ureteral duplication in a young alpaca

A seven-month-old male alpaca (Lama pacos) with signs of abdominal straining was examined. A fluid-filled structure was palpable in the mid-abdominal region, and ultrasonography revealed a hydronephrosis of the right kidney, with an associated mega-ureter. The affected kidney was removed and the clinical signs resolved. Histological examination of the kidney revealed the unusual congenital abnormality of ureteral duplication. It is suggested that the hydronephrosis developed as a result of this underlying condition.

Chronic renal failure associated with nephrolithiasis, ureterolithiasis, and renal dysplasia in a 2-year-old quarter horse gelding

A 2-year-old quarter horse gelding presented for evaluation of polyuria and polydipsia. Azotemia was detected on serum chemistry profile. Small, misshapen, hyperechoic kidneys with decreased corticomedullary demarcation, hydronephrosis, and a right nephrolith were noted ultrasonographically. The diagnosis of end-stage kidney disease and dysplasia was made histopathologically using ultrasound-guided biopsy. Two ureteroliths were found in the right ureter via cystoscopy, and a nephrolith was seen in the right kidney at necropsy. Clinical, ultrasonographic, and pathologic features of equine urolithiasis and renal dysplasia are discussed.

Bilateral hydroureter and hydronephrosis in a nine-year-old female German shepherd dog

A nine-year-old female German shepherd dog was presented in severe renal failure. Clinical and ultrasonographic examination revealed the presence of adrenal neoplasia, bilateral hydroureter and hydronephrosis but no evidence of urolithiasis or bladder neoplasia. In the absence of anuria, therapy for the renal failure was attempted but the azotaemia did not improve. Remarkably, bilateral hydroureter appeared to have been induced by a past routine surgical procedure--ovariohysterectomy.

Obstructive uropathy and hydronephrosis in male KK-Ay mice: a report of cases

Uropathy associated with hydronephrosis was observed frequently in our male KK-Ay mouse colony during a long-term study of diabetes. The lesion occurred in 24 of the 31 KK-Ay male mice and accounted for the greatest number of spontaneous deaths among them. It was observed after 4 months of age and involved about hard plugs of altered seminal material resembling the seminal vesicle secretion. The plugs became impacted in the urethral bulb and the bladder. The penile anatomy, with its flexure, pressure on the urethra from the bulbocavernosus muscle, and the characteristic ability of the seminal fluid to easily coagulate to form the vaginal plug may have contributed to the lesion. Correlation between development of the uropathy and diabetes has not been established.

Ultrasonographic detection of adrenal gland tumor and ureterolithiasis in a guinea pig

A 5-year-old guinea pig was presented to the University of Berne Small Animal Radiology Department for an ultrasound examination of the abdomen to confirm a suspected diagnosis of Cushing's syndrome. The patient had bilateral alopecia, was apathic and obese. Ultrasonographically, a tumor of the left adrenal gland, obstruction of the left ureter by an ureterolith, as well as hydronephrosis of the left kidney were detected. During surgery to relieve the ureteral obstruction the adrenal gland tumor was removed. The guinea pig died post-operatively due to blood loss. The left adrenal gland tumor was found histopathologically to be an adenoma and the right adrenal gland also had multiple small adenomas, but grossly appeared normal. The ureterolith was analyzed and found by x-ray diffraction to consist of calcium carbonate.

Congenital defects in northern elephant seals stranded along the central California coast

Eleven cases of congenital anomalies were identified in 210 (5%) juvenile northern elephant seals (Mirounga angustirostris) found stranded along the central California (USA) coast from 1 January 1988 to 31 December 1995. Seven individuals had mild-to-moderate hydrocephalus involving the lateral ventricles bilaterally, or the lateral and third ventricles. Two animals had severe cardiac anomalies: hypoplasia of the right ventricle with overriding aorta, and ventricular septal defect. Other anomalies included single cases of hydronephrosis, focal pulmonary dysplasia, and congenital epidermal angiomatosis. Common intercurrent disease processes were verminous pneumonia and arteritis, verminous enteritis and coliti, and splenic and hepatic hemosiderosis. The more severe anomalies were considered to be the cause of debilitation and stranding. Milder anomalies were found incidentally during routine gross necropsy and histopathologic examination.

Early and persistent up-regulated expression of renal cortical osteopontin in experimental hydronephrosis

The mechanical disturbance after unilateral ureteral obstruction (UUO) is a nonimmune stimulus that is capable of eliciting a florid macrophage infiltration of the kidney and subsequent post-inflammatory renal scarring. Osteopontin has potential chemoattractant activity and, for this reason, we delineated the kinetics of its expression in the renal cortex of rats with UUO. Whole body X-irradiation and reversal of UUO were utilized as interventional maneuvers to give additional pathobiological insight into this protein's role in the response of the kidneys to ureteral obstruction. Increased osteopontin mRNA levels in obstructed kidneys versus contralateral unobstructed specimens were evident as early as 4 hours after UUO and steadily increased at 12, 24, 48, and 96 hours after UUO. Both X-irradiation and reversal of UUO failed to significantly modulate renal cortical osteopontin mRNA expression at all of the above time points. Paralleling the increments in renal cortical osteopontin mRNA levels were significant elevations in the cortical renal interstitial macrophage number, which was significantly diminished by previous X-irradiation but not reversal of UUO. Focal labeling of osteopontin was noted in both tubular and Bowman's capsular epithelium in obstructed kidneys as early as 4 hours after UUO, whereas, in the contralateral unobstructed specimens, there was only faint staining in Bowman's capsule. By 96 hours after UUO, obstructed kidneys exhibited intense, diffuse staining for osteopontin in both tubules and Bowman's capsule. Osteopontin's immunolocalization was not modulated by X-irradiation or reversal of UUO. These data support the contention that osteopontin is involved in the accumulation of macrophages within the peritubular and periglomerular interstitium in the obstructed renal cortex.

[Urolithiasis in male sheep and goats. Clinical picture, therapeutic possibilities and prognostic evaluation]

A report is given about the course of urolithiasis in 34 rams and 18 castrated billy-goats. Different therapeutic procedures of this disease are discussed. Concrements in the processus urethrae (n = 27) were removed by amputation of this organ. In animals with a further proximal situated urethral obstruction an ischiourethrostomy was done (n = 7). 21 animals were healed and 9 animals were sent home in an improved condition, but with urine leaking from an artificial opening. Complications as: hyperdistended and ruptured bladder (n = 9) or hydronephrosis caused by severe urine pressure were mostly seen when the diagnosis urolithiasis had been urine pressure were mostly seen when the diagnosis urolithiasis had been confirmed too late, or when the animals had been treated for several days only with analgetics or spasmolytics. Urine cellulitis of the ventral abdomen (n = 11) had not always a bad prognosis. 7 of 11 cases were healed.

Renal dysplasia and benign ureteropelvic polyps associated with hydronephrosis in a foal

A 4-month-old male Trakehner foal with a history of hematuria, poor growth, and abnormal hair was found to have unilateral hydronephrosis and hydroureter, as determined by ultrasonography and surgical exploration. Nephrectomy and ureterectomy were performed as treatment. Gross examination of the ureter and kidney revealed renal pelvic and ureteral polyps causing obstruction and subsequent hydronephrosis. The histologic features were consistent with renal dysplasia. The polyps and renal dysplasia were likely to be congenital, but the etiopathogenesis is not known. The finding that urinary outflow obstruction can disrupt nephrogenesis and lead to renal dysplasia supports the view that the polyps developed, blocked urine flow, and caused the hydronephrosis and renal dysplasia in the foal.

Postoperative evaluation of renal function after surgical correction of a ureterovaginal fistula in a cat

Unilateral hydronephrosis and urinary incontinence, secondary to a ureterovaginal fistula, were corrected in a cat after surgical excision of the fistula and implantation of the affected ureter into the bladder. Salvage of the kidney was attempted because underlying chronic bilateral renal disease was suspected. Renal scintigraphy was used to monitor improvement in the function of the previously obstructed kidney after surgery.

Hereditary hydronephrosis in C57L/MsNrs mice

Inbred C57L/MsNrs mice (66 males and 72 females) maintained at the National Institute of Health, Japan, were examined grossly for hydronephrosis. Unlike the hydronephrotic strains of mice reported so far, C57L mice showed no sex-related difference in the incidence (62% in males and 75% in females; P > 0.05) and severity of hydronephrosis. The right kidney was more severely affected than the left kidney in both sexes. Age appeared to have no influence on the incidence.

Chronic partial obstructive urolithiasis causing hydronephrosis and chronic renal failure in a steer

A 13-month-old Angus steer was examined with a 6-week history of lethargy, malaise and dribbling urine. Laboratory exam revealed crystalluria and poor renal function. Ultrasound revealed hydronephrosis and hydroureter. Euthanasia was chosen because of a poor prognosis for economic recovery. Necropsy demonstrated numerous calculi causing partial urethral obstruction approximately 25 cm from the end of the penis. Secondary renal changes were confirmed. Urolithiasis occurs commonly in ruminants. Secondary obstruction is usually complete with severe consequences. This is the first report of chronic partial obstructive urolithiasis resulting in endstage renal disease.

Continent jejunal reservoir (Kock pouch) for urinary diversion in dogs

Urinary diversion by transplantation of both ureters into a reservoir constructed from 60 cm of jejunum was performed in six clinically normal dogs. The reservoir was connected to a stoma on the abdominal wall through a valve constructed from a short segment of intussuscepted bowel to provide continence. The reservoir was emptied three times daily by catheterization. One dog did not survive the surgical procedure and two dogs died within 1 week of surgical complications. The postoperative capacity of the reservoir in surviving dogs was 100 to 200 mL; it increased during the first month to 600 to 750 mL. Continence was excellent in two dogs. One dog was continent until month 2, when partial slippage of the intussusception occurred. A reversible hyponatremic, hypochloremic, hypokalemic metabolic acidosis developed. Bacteriuria was not responsive to systemic or local instillation of antibiotics. Ascending pyelonephritis, hydroureter, and hydronephrosis occurred in two dogs. Struvite urinary calculi formed in one dog. The procedure as described would be unsuitable for clinical use in dogs.

Gastric conduit urinary diversion in normal dogs. Part I, Upper urinary tract structure, function, and sepsis

The urinary bladder of 10 clinically normal dogs was excised and the ureters were implanted into an isolated, vagotomized gastric segment derived from the fundic region of the stomach. The gastric segment was closed to form a conduit. Continence was maintained with a modified Kock "nipple valve" created from an isolated segment of ileum. Four dogs were euthanatized by day 30 because of complications related to the early onset of renal failure and electrolyte alterations. Six dogs were euthanatized on day 150. Ureteral dilatation, hydronephrosis, and decreased endogenous creatinine clearance rates were measured in all dogs at the end of the survival period. Pyelonephritis was diagnosed histologically in seven dogs. Positive renal cultures were obtained from seven dogs at necropsy. It was concluded that gastric conduit urinary diversion is unsatisfactory for long-term or short-term clinical use in dogs.

Hydronephrosis and pyelonephritis associated with an anomalous vas deferens in a bull

Hydronephrosis and pyelonephritis were diagnosed in a 2-year-old Limousin bull. Salient historical and clinical observations included weight loss, anorexia, intermittent colic, polyuria, polydypsia, and an ammoniacal breath odor. Intravenous treatment with fluids and antibiotics did not induce a favorable response. An anomalous vas deferens was observed on postmortem examination. The vas deferens ended in a blind polyp that protruded into the lumen of the urethra. This polyp may have caused chronic intermittent obstruction, predisposing to the hydronephrosis and pyelonephritis.

Reduction of hydronephrosis and hydroureter associated with ectopic ureters in two dogs after ureterovesical anastomosis

Severe hydronephrosis and hydroureter associated with ectopic ureters were diagnosed in 2 dogs. Surgical transplantation of the ectopic ureters into the urinary bladder resulted in urinary continence in both dogs. Intravenous urography revealed a marked decrease in the size of hydronephrosis and hydroureter in both dogs 28 to 35 weeks after surgery. In 1 dog with bilateral ureteral ectopia, kidney size and renal function remained normal for 5 years after surgery. A dog with one ectopic ureter and an associated ureterocele had a marked reduction in size of the affected kidney and an apparent decrease in function of that kidney, as indicated by decreased opacification on an intravenous urogram.

Spontaneous hydronephrosis in C57BL/KsJ mice

Spontaneous hydronephrosis was observed in 15 of 33 necropsied C57BL/KsJ mice. The gross and histological appearances of these lesions are described. Spontaneous hydronephrosis is rare in mice and has not been previously described in this strain. At least four different mutations are reported to cause hydronephrosis in the mouse; each is associated with a high incidence of severe skeletal defects. Because no skeletal malformations were observed in the present study, it is likely that either a multigenic trait which has been present for a long time but is expressed variably, or a mutation other than those previously described may be responsible for hydronephrosis in C57BL/KsJ mice.