Case report: Chylopericardium secondary to dialysis catheter related jugular venous thrombosis in two dogs receiving long-term hemodialysis.

Chylopericardium is a rare entity in veterinary medicine. In this report we document the development of chylopericardium in two dogs undergoing chronic hemodialysis. An 11-year-old female spayed Labrador retriever (Case 1) presented with acute coughing and lethargy 2 months following initial dialysis catheter placement and initiation of dialysis therapy for severe azotemia. Echocardiography demonstrated severe pericardial effusion and cardiac tamponade. Pericardial fluid analysis was consistent with chylous effusion. The dog underwent a subtotal pericardiectomy with thoracic duct ligation, and a PleuralPort™ was placed. The patient continued to receive outpatient hemodialysis therapy after pericardiectomy for several months until she died acutely at home. A 4-year-old male neutered Doberman (Case 2) was being treated for 2 months with outpatient hemodialysis for management of chronic kidney disease. On presentation for the 17th hemodialysis treatment, the patient had increased respiratory rate. Echocardiography demonstrated pleural and pericardial effusions, and fluid analysis in both cavities was consistent with chylous effusion. Use of tissue plasminogen activator (TPA), clot removal and replacement of the catheter was attempted; however pleural and pericardial effusion continued. The patient was euthanized after 25 hemodialysis sessions as owners elected not to pursue more procedures. In both cases, the cause of the chylopericardium was suspected to be secondary to catheter-associated thrombosis and/or stenosis based on multiple imaging modalities. Despite use of rivaroxaban and clopidogrel concurrently in each case, the chylous effusion persisted. This case report describes clinical details of a rare complication of long-term indwelling dialysis catheters in two dogs.

Bilateral external jugular vein anomalies preventing hemodialysis catheter placement in a cat with anuria secondary to Lilium species intoxication.

Case series summary: A 2-year-old female spayed Abyssinian cat was evaluated for lethargy and inappetence that first occurred approximately 4 days prior. In addition, urination had not been observed by the owner for 5 days. A Lilium species plant had been brought into the house approximately 5 days before initial evaluation, and intoxication was therefore suspected. Bloodwork revealed anemia, severe azotemia and hyperkalemia. As the cat was anuric with severe azotemia, hyperkalemia and fluid overload, intermittent hemodialysis was recommended. Attempts were made to place a hemodialysis catheter into the external jugular veins bilaterally, but after initial successful venipuncture, the instrumentation would not pass into either vein. During fluoroscopic angiography, no internal jugular veins or external jugular veins caudal to the thoracic inlet were visualized and venous drainage from the head occurred via the vertebral veins. Owing to the anomalous anatomy in the cervical region, a hemodialysis catheter could not be placed into either jugular vein. Alternative sites for the placement of an extracorporeal catheter were discussed with the owner, but humane euthanasia was elected. Relevance and novel information: To the authors' knowledge, this is the first report of a cat with bilateral external jugular vein anomalies resulting in blind endings that did not communicate with the vena cava. This was discovered during attempts to place a hemodialysis catheter for the management of anuric renal failure secondary to Lilium species intoxication. While this anatomical variation is likely uncommon, it is an important differential to consider when faced with challenging external jugular vein catheterizations in feline patients.

A 20-year scoping review of the veterinary interventional radiology and interventional endoscopy literature (2000-2019).

BACKGROUND: Interventional radiology (IR) and interventional endoscopy (IE) have broad potential for minimally invasive therapy in veterinary patients, but the scope of original peer-reviewed veterinary IR/IE research publications has not been described. OBJECTIVES: Catalogue published applications and indications for noncardiac therapeutic IR/IE in animals and describe type and quality of veterinary IR/IE research over 20 years. METHODS: Highly-cited veterinary journals were searched to identify articles published 2000 to 2019 involving therapeutic IR/IE applications for clinical veterinary patients. Articles were assigned a level of evidence (LOE) according to published standards. Authorship, animal data, study design, and interventions were described. Change in publication rate, study size, and LOE of IR/IE articles over time was analyzed. RESULTS: One hundred fifty-nine of 15 512 (1%) articles were eligible, including 2972 animals. All studies were low LOE and 43% were case reports with ≤5 animals. Number of IR/IE articles per year (P < .001), proportion of journals' articles pertaining to IR/IE (P = .02), and study size (P = .04) all increased over time, but LOE (P = .07) did not. Common target body systems were urinary (40%), digestive (23%) respiratory (20%), and vascular (13%). Common indications were nonvascular luminal obstructions (47%), object retrieval (14%), and congenital anomalies (13%). Most procedures involved indwelling medical devices or embolic agents, whereas tissue resection and other procedures were less common. Procedures utilized fluoroscopy (43%), endoscopy (33%), ultrasound (8%), digital radiography (1%), or fluoroscopy in combination with other modalities (16%). CONCLUSIONS: Treatments involving IR/IE have wide applicability in veterinary medicine but large, rigorous, and comparative studies describing these procedures are lacking.

Ultrafiltration during intermittent hemodialysis in dogs with acute kidney injury.

BACKGROUND: Ultrafiltration is performed to alleviate fluid overload in dogs with acute kidney injury (AKI) undergoing intermittent hemodialysis (IHD). OBJECTIVES: To describe prescription patterns for ultrafiltration in dogs receiving IHD for AKI and risk factors for ultrafiltration-related complications. ANIMALS: Seventy-seven dogs undergoing 144 IHD treatments between 2009 and 2019. METHODS: Medical records of dogs receiving IHD for AKI were reviewed. The initial 3 IHD treatments in which ultrafiltration was prescribed were included. Ultrafiltration-related complications were defined as those requiring an intervention such as transient or permanent discontinuation of ultrafiltration. RESULTS: Mean fluid removal rate per treatment was 8.1 ± 4.5 mL/kg/h. Ultrafiltration-related complications occurred in 37/144 (25.7%) of treatments. Hypotension was rare (6/144, 4.2% of treatments). No ultrafiltration-related complications resulted in deaths. The mean prescribed fluid removal rate per treatment was higher in dogs with ultrafiltration-related complications than without (10.8 ± 4.9 mL/kg/h vs 8.8 ± 5.1 mL/kg/h, respectively; P = .03). The mean delivered fluid removal rate per treatment was significantly lower in dogs with UF-related complications compared to those without complications (6.8 ± 4.0 mL/kg/h vs 8.6 ± 4.6 mL/kg/h, respectively; P = .04). Variables associated with ultrafiltration-related complications (P < .05) included central venous oxygen saturation, body temperature before IHD treatment, total extracorporeal circuit volume and BUN at the end of IHD treatment. CONCLUSIONS AND CLINICAL IMPORTANCE: Ultrafiltration during IHD in dogs with AKI is overall safe. Higher prescribed ultrafiltration rates were associated with increased risk of complications. Decrease in central venous oxygen saturation is associated with ultrafiltration-related complications, emphasizing the utility of in-line blood monitoring.

MRI characteristics of canine prostatic neoplasia.

Magnetic resonance imaging (MRI) has been used to evaluate dogs with suspected prostatic neoplasia, however, published studies describing MRI characteristics of canine prostatic neoplasia are currently lacking. The aims of the current retrospective case series study were to describe MRI findings of the pelvic region in dogs with a histopathologic or cytologic diagnosis of prostatic neoplasia. Retrospective analysis of these images was then performed by a board-certified veterinary radiologist for shared imaging characteristics. The most consistent characteristics were heterogeneous hyperintensity of the tumor on T2-weighted images (10/10) and short tau inversion recovery images (10/10), prostatic capsular margin distortion by the tumor (10/10), cavitations (10/10), complete effacement of the prostatic architecture (9/10), neurovascular bundle (NVB) compression or invasion (9/10), heterogeneous isointensity of the tumor on T1-weighted images (9/10), and strong contrast enhancement of the tumor (8/10). Additional features included an overlying pattern of distorted radiating striations (7/10), regional lymphadenomegaly (5/10), mineralization within the mass (5/10), urinary bladder trigone involvement (6/10), and post-prostatic urethral involvement (7/10). These findings supported the use of MRI as an adjunct imaging modality for diagnosis and therapeutic planning of prostatic neoplasia and including prostatic neoplasia as a likely differential diagnosis for dogs with these MRI characteristics.

Effect of standard-dose and high-dose pimobendan on select indices of renal and cardiac function in dogs with American College of Veterinary Internal Medicine stage B2 myxomatous mitral valve disease.

BACKGROUND: Pimobendan might have favorable effects on renal function but this has not been well-studied in dogs with myxomatous mitral valve disease (MMVD). OBJECTIVES: Determine the effects of standard-dose (SD_pimo) and high-dose pimobendan (HD_pimo) on glomerular filtration rate (GFR) and cardiac size and function in dogs with preclinical MMVD. ANIMALS: Thirty nonazotemic dogs with stage B2 MMVD. METHODS: Prospective, randomized, double-blinded, placebo-controlled clinical study. Dogs had an echocardiographic examination, assessment of GFR (iohexol clearance), N-terminal probrain natriuretic peptide (NT-proBNP), and quality of life (QOL) score at baseline and 7 to 10 days after placebo (n = 6), SD_pimo 0.2 to 0.3 mg/kg q12 (n = 12), or HD_pimo 0.5 to 0.6 mg/kg q12h (n = 12). RESULTS: No significant differences in GFR or QOL scores were detected between groups (P ≥ .07). After HD_pimo, the mean [SD] percent change of NT_proBNP (-46.1 [20.2]%), left atrial volume (LAV; -27.1 [16.9]%), left ventricular end-diastolic volume (EDV; -21.8 [15.0]%), and end-systolic volume (ESV; -55.0 [20.7]%) were significantly different (P ≤ .004) from placebo (0.5 [19.9]%, 1.3 [15.6]%, -0.2 [8.2]%, -7.3 [35.6]%, respectively) but not the percent change after SD_pimo (-36.6 [16.1]%, -22.7 [14.9]%, -16.7 [12.5]%, -41.6 [14.8]%, respectively; P > .05). After SD_pimo, percent change of NT_proBNP, LAV, EDV, and ESV were significantly different from placebo (P < .05). CONCLUSIONS AND CLINICAL IMPORTANCE: Results suggest that pimobendan (SD_pimo or HD_pimo) might not affect renal function in nonazotemic dogs with stage B2 MMVD. High-dose pimobendan did not demonstrate advantages over SD_pimo within the constraints of our study.

Diagnosis, management, and outcome of urethral obstruction secondary to the capsule associated with the artificial urethral sphincter device.

BACKGROUND: Urethral obstruction secondary to artificial urethral sphincter (AUS) implantation is a recognized complication in dogs. However, urethral obstruction secondary to AUS-associated capsule formation has been described rarely. HYPOTHESIS: Describe clinical and diagnostic findings, management, and outcome in 6 dogs with urethral obstruction secondary to AUS-associated capsule formation. ANIMALS: Six client-owned dogs. METHODS: Retrospective study. Medical records between January 1, 2010, and June 30, 2021, were reviewed to identify dogs with urethral obstruction associated with the AUS device. RESULTS: The AUS device was implanted a median of 884 days (range, 20-2457 days) before presentation for urethral obstruction. Median age at time of urethral obstruction was 4.7 years (range, 3.1-8.7 years). Clinical signs at the time of urethral obstruction were stranguria (n = 4), pollakiuria (3), weak urine stream (2), and worsened urinary incontinence (1). In all dogs, the urethra was noted to be stenotic during urethroscopy and positive contrast cystourethrography. All dogs underwent surgery, and a fibrous capsule associated with the AUS was found to be causing urethral stenosis. Resolution of urethral obstruction occurred in all dogs after transection or removal of the capsule. Positive bacterial cultures were obtained from the capsule, AUS, or both in all dogs. Recurrence of urethral obstruction had not occurred in any dog at the time of follow-up. CONCLUSIONS AND CLINICAL IMPORTANCE: Urethral obstruction secondary to capsule formation is an uncommon but clinically important complication associated with use of the AUS. Continued investigation is needed to evaluate this complication more thoroughly, and its possible association with infection.

Untargeted Metabolomics Identify a Panel of Urinary Biomarkers for the Diagnosis of Urothelial Carcinoma of the Bladder, as Compared to Urolithiasis with or without Urinary Tract Infection in Dogs.

Urothelial carcinoma (UC), the most common urologic cancer in dogs, is often diagnosed late because the clinical signs are shared by other non-malignant lower urinary tract disorders (LUTD). The urine-based BRAFV595E test for UC is highly effective only in certain breeds; hence additional non-invasive biomarkers of UC are needed. Here, urine from dogs with UC (n = 27), urolithiasis (n = 8), or urolithiasis with urinary tract infection (UTI) (n = 8) were subjected to untargeted metabolomics analyses, using GC-TOF-MS for primary metabolites, QTOF-MS for complex lipids, and HILIC-QTOF MS for secondary and charged metabolites. After adjusting for age and sex, we identified 1123 known metabolites that were differentially expressed between UC and LUTD. Twenty-seven metabolites were significant (1.5 ≤ log2FC ≤ −1.5, adjusted p-value < 0.05); however, 10 of these could be attributed to treatment-related changes. Of the remaining 17, 6 (hippuric acid, N-Acetylphenylalanine, sarcosine, octanoylcarnitine, N-alpha-methylhistamine, glycerol-3-galactoside) discriminated between UC and LUTD (area under the ROC curve > 0.85). Of the 6 metabolites, only hippuric acid and N-alpha-methylhistamine were discriminatory in both male (n = 20) and female (n = 23) dogs, while sarcosine was an effective discriminator in several breeds, but only in females. Further investigation of these metabolites is warranted for potential use as non-invasive diagnostic biomarkers of dogs with UC that present with LUTD-related clinical signs.

Outcome of dogs with bone marrow suppression secondary to Sertoli cell tumour.

Sertoli cell tumours are one of the most common canine testicular neoplasia. These tumours are significantly more likely to arise in cryptorchid dogs and are often functional, oestrogen-secreting tumours which can lead to fatal myelotoxicity. The goal of this study was to describe the outcome of dogs with oestrogen-induced bone marrow suppression secondary to Sertoli cell tumours in seven client-owned dogs. Medical records from April 1, 2011 through April 1, 2021 were reviewed to identify dogs that underwent surgical management of a Sertoli cell tumour with documented bone marrow suppression. Overall, 5/7 dogs required transfusion of blood products peri-operatively. Cases 1 and 6 received a transfusion of packed red blood cells (RBC) prior to surgery and case 5 required a transfusion of whole blood. Case 1 also required a transfusion of platelets before surgery. Post-operatively, cases 1 and 2 received packed RBC's and case 6 received two transfusions of whole blood. Case 3 required transfusions of both fresh frozen plasma and platelets post-operatively. All dogs survived to discharge and 6/7 dogs had documented improvement in haematopoietic values. Two dogs remained chronically thrombocytopenic. The median hospital stay was 4 days. One dog died within 4 weeks of surgery from worsening pancytopenia. Survival for greater than 1 year was documented in 4/7 dogs, and one dog was lost to follow-up 4 months post-operatively. One dog remained severely pancytopenic 4 weeks post-operatively and received oral lithium treatment. Improvements in all blood cell lines were observed within the 4 weeks and resolution of pancytopenia within 6 weeks. Historically, the prognosis for dogs with bone marrow suppression secondary to Sertoli cell tumours was guarded to poor. This report documented improved outcomes for dogs that underwent surgery, including one dog that received lithium chloride as treatment for Sertoli cell tumour-induced bone marrow suppression.

Association of ultrasonographic features with histologic findings in 71 dogs with protein-losing nephropathy (2008-2018).

OBJECTIVE: To determine whether ultrasonographic features in dogs with protein-losing nephropathy (PLN) were associated with renal biopsy findings and compare corticomedullary ratios between dogs with PLN versus non-renal disease. ANIMALS: 71 dogs with PLN and 33 dogs without renal disease. PROCEDURES: Medical records and archived ultrasonographic images for dogs with PLN that underwent renal biopsy between 2008 and 2018 were reviewed. Corticomedullary ratios were measured. RESULTS: In dogs with PLN, median serum creatinine and BUN concentrations and urine-protein-to-creatinine-ratio prior to renal biopsy were 3.4 mg/dL (interquartile range [IQR], 1.2 to 5.3 mg/dL), 80 mg/dL (IQR, 28 to 105 mg/dL), and 11.4 (IQR, 6.4 to 18.3), respectively. Histologic abnormalities within the tubulointerstitial space were associated with cortical echogenicity. Gastric wall thickness > 5 mm was associated with a histologic diagnosis of acute glomerular disease. Dogs with immune complex-mediated glomerular disease were more likely to have abnormal gastric mural architecture. Other ultrasonographic features of the kidneys, liver, and stomach and the presence of ascites did not help to differentiate immune complex-mediated from non-immune complex-mediated glomerular disease, acute from chronic disease, or amyloid from non-amyloid disease or distinguish whether tubulointerstitial disease was present or absent. Median left corticomedullary ratio for 66 dogs with PLN (1.2) was significantly higher than that for the 33 dogs without renal disease (1.0). CLINICAL RELEVANCE: Ultrasonographic features were poorly associated with specific pathological disorders in dogs with PLN. In this study, the corticomedullary ratio was higher in dogs with PLN, indicating the presence of cortical thickening, but the clinical relevance is unknown.

Procedural description and prospective evaluation of short-term outcome for the use of prostatic artery embolization in dogs with carcinoma of the prostate.

OBJECTIVE: To describe the procedure of prostatic artery embolization (PAE) in dogs with prostatic carcinoma and to evaluate the short-term outcome for treated dogs. ANIMALS: 20 client-owned dogs with prostatic carcinomas between May 2014 and July 2017. PROCEDURES: In this prospective cohort study, dogs with carcinoma of the prostate underwent PAE with fluoroscopic guidance. Before and after PAE, dogs underwent CT and ultrasonographic examinations of the prostate, and each owner completed a questionnaire about the dog's clinical signs. Results for before versus after PAE were compared. RESULTS: Prostatic artery embolization was successfully performed in all 20 dogs. Tenesmus, stranguria, and lethargy were significantly less common 30 days after PAE (n = 2, 1, and 0 dogs, respectively), compared with before PAE (9, 10, and 6 dogs, respectively). Median prostatic volume was significantly less 30 days after PAE (14.8 cm3; range, 0.4 to 48.1 cm3; interquartile [25th to 75th percentile] range, 6.7 to 19.5 cm3), compared with before PAE (21.7 cm3; range, 2.9 to 77.7 cm3; interquartile range, 11.0 to 35.1 cm3). All dogs had a reduction in prostatic volume after PAE, with a median prostatic volume loss of 39.4% (95% CI, 20.3% to 59.3%). CONCLUSIONS AND CLINICAL RELEVANCE: Prostatic artery embolization was associated with decreased prostate volume and improved clinical signs in this cohort. The short-term response to PAE appears promising, and evaluation of the long-term impact on survival time is needed.

Use of percutaneous microwave ablation in the treatment of retroperitoneal neoplasia in three dogs.

CASE DESCRIPTION: 3 dogs with retroperitoneal masses (2 renal and 1 located near the diaphragm) were treated by percutaneous microwave ablation (MWA). CLINICAL FINDINGS: Dogs between 11 and 13 years of age weighing between 13.7 and 43.8 kg had either a renal mass (n = 2) or a mass located in the caudodorsal aspect of the retroperitoneal space near the right side of the diaphragm (1). Cytology revealed that one of the renal masses and the mass located near the diaphragm were malignant neoplasias. Findings on cytologic evaluation of a sample of the other renal mass was nondiagnostic. Maximum mass diameters ranged between 1.4 and 2.5 cm. TREATMENT AND OUTCOME: All dogs were treated by percutaneous MWA. Probes were directed into tumors by use of ultrasound and CT guidance, and microwave energy was applied to each mass. Findings on imaging of each mass following MWA was consistent with successful treatment. No intraprocedural or major postprocedural complications occurred, and all dogs were discharged from the hospital within 3 days of treatment. Two dogs died at 3 and 21 months after MWA with no known local recurrence; 1 dog was still alive 64 months after treatment. CLINICAL RELEVANCE: Although the indications for MWA in the treatment of neoplasia in companion animals are limited, the outcomes of dogs in the present report provided preliminary evidence that percutaneous MWA can be safely used to effectively treat retroperitoneal neoplasia. This procedure was successfully performed with image guidance in all 3 dogs.

Suspected contrast-induced nephropathy in three sequential patients undergoing computed tomography angiography and transarterial embolization for nonresectable neoplasia.

CASE DESCRIPTION: During the same week, 3 sequential patients (a 10-year-old 8.7-kg spayed female poodle cross [dog 1], 13-year-old 2.6-kg spayed female domestic longhair cat, and 13-year-old 9.0-kg castrated male mixed-breed dog [dog 2]) underwent CT-angiography (day 0) and transarterial embolization (day 1) for nonresectable hepatocellular carcinoma (n = 2) or prostatic carcinoma (1). CLINICAL FINDINGS: Contrast-induced nephropathy (CIN) was suspected in all animals on the basis of higher serum creatinine concentrations after contrast medium administration (exposure), compared with baseline concentrations before exposure, consistent with CIN definitions. The total dose of contrast medium was < 3 mL/kg for each exposure. For all 3 patients, creatinine concentration peaked at a median of 3 days (range, 2 to 3 days) after the first exposure (day 0), and the median absolute and relative increases in creatinine concentration after exposure (vs baseline concentrations before exposure) were 2.9 mg/dL (range, 2.2 to 3.7 mg/dL) and 410% (range, 260 to 720%), respectively. TREATMENT AND OUTCOME: The patients received individually tailored supportive care for acute kidney injury. Serum creatinine concentrations began to improve at a median of 4 days (range, 3 to 4 days) and returned to within reference limits at a median of 7 days (range, 3 to 13 days) following initial exposure. CLINICAL RELEVANCE: CIN should be considered as a potential complication following IV administration of contrast medium. Short-term outcome following CIN can be excellent with supportive care.

Treatment of a Congenital Imperforate Vestibulovaginal Junction and Secondary Hydrocolpos With Endoscopic Laser Ablation in Two Dogs.

Two dogs were evaluated for clinical signs including dysuria, stranguria, and/or dyschezia. Physical examination findings were consistent with a caudal abdominal and intra-pelvic mass. Imaging with abdominal ultrasonography confirmed the presence of a tubular fluid-filled structure. In 1 dog computed tomography identified the fluid-filled structure to be the vagina and hydrocolpos was suspected. Endoscopic evaluation of the urogenital tracts identified imperforate vaginas in both dogs, and endoscopic-guided laser ablation was used to create a vaginal opening into the vestibule. Initial response to treatment was positive in both dogs, although 1 dog developed a recurrence of hydrocolpos 1-month after treatment. Endoscopic laser ablation provided a minimally invasive option for opening an imperforate vagina and no procedural complications occurred. Further evaluation is needed to determine the long-term effectiveness of this procedure.

Retrospective Evaluation of Acute Kidney Injury After Zoledronic Acid Administration to Dogs With Malignant Osteolysis.

Zoledronic acid (ZOL) is an intravenous bisphosphonate indicated for the use of hypercalcemia of malignancy and management of bony metastases. Its therapeutic effect lies in the targeting of malignant osteoclasts; however, administration can be associated with renal toxicity. The objective of this retrospective study was to evaluate the frequency and severity of acute kidney injury (AKI) following ZOL administration in a cohort of cancer-bearing dogs. A pharmacy search was conducted to identify dogs that received a dose of ZOL between June 2016 and July 2019. Inclusion criteria included baseline and post-treatment chemistry panels. Medical records were reviewed to obtain clinical data including signalment, dose, dosage, number of treatments administered, and changes in renal function. Forty-four dogs met the inclusion criteria. Median number of doses administered was three [interquartile range (IQR), 2-5]. The median highest creatinine value occurred after a median of one dose (IQR, 1-2 doses) compared with the median highest value of blood urea nitrogen, phosphorus, and potassium, which occurred after a median of two doses (IQR, 1-3). Six (13.6%) dogs developed an AKI, and one dog (2.3%) had progression of an existing azotemia after treatment with ZOL was initiated. Two dogs (4.5%) had ZOL treatment discontinued secondary to development of azotemia. Use of concurrent administration of non-steroidal anti-inflammatory drugs or anesthesia did not significantly increase the risk of AKI in this cohort of dogs. Acute kidney injury is observed infrequently in cancer-bearing dogs treated with ZOL and is generally mild to moderate in severity; discontinuation of ZOL due to AKI is uncommon.

NEOURETEROCYSTOSTOMY AND URETHRAL STENT PLACEMENT IN A BLACK-HANDED SPIDER MONKEY (ATELES GEOFFROYI).

A 27-y-old female black-handed spider monkey (Ateles geoffroyi) was evaluated 13 d after an ovariohysterectomy because of abdominal distension, anorexia, and absent urination. The animal was diagnosed with a uroabdomen and urethral obstruction from computed tomographic findings and fluid creatinine levels. During exploratory laparotomy, a defect in the right ureter was confirmed as the source of the uroabdomen. Utilizing intraoperative fluoroscopy, a urethral obstruction with an irregular luminal filling defect was evident. A self-expanding nitinol urethral stent was placed, and a ureteral transposition was performed. Two months after the procedure, the animal developed dysuria, a urinary tract infection, recurrent bladder distension and a partial urethral obstruction. Treatment with prazosin 1 mg/kg PO q12h improved urination. Reobstruction of the urethra occurred 17 mo postsurgery, and the animal was euthanatized. On postmortem examination, the animal had ingrowth into the stent with proliferative granulation tissue, detrusor muscle degeneration, pelvic adhesions, cystitis, pyelonephritis, and hydronephrosis.

Urolithiasis in dogs: Evaluation of trends in urolith composition and risk factors (2006-2018).

BACKGROUND: Urolithiasis is a common and often recurrent problem in dogs. OBJECTIVE: To evaluate trends in urolith composition in dogs and to assess risk factors for urolithiasis, including age, breed, sex, neuter status, urolith location, and bacterial urolith cultures. SAMPLE POPULATION: A total of 10 444 uroliths and the dogs from which they were obtained. METHODS: The laboratory database at the UC Davis Gerald V. Ling Urinary Stone Analysis Laboratory was searched for all urolith submissions from dogs between January 2006 and December 2018. Mineral type, age, breed, sex, neuter status, urolith location, and urolith culture were recorded. Trends were evaluated and variables compared to evaluate risk factors. RESULTS: Calcium oxalate (CaOx) and struvite-containing uroliths comprised the majority of all submissions from dogs, representing 47.0% and 43.6%, respectively. The proportion of CaOx-containing uroliths significantly decreased from 49.5% in 2006 to 41.8% in 2018 (P = .006), with no change in the proportion of struvite-containing urolith submissions. Cystine-containing uroliths comprised 2.7% of all submissions between 2006 and 2018 and a significant nonlinear increase in this mineral type occurred over time (1.4% of all submissions in 2006 to 8.7% in 2018; P < .001). Of all cystine-containing uroliths, 70.3% were from intact male dogs. Age, breed, and sex predispositions for uroliths were similar to those previously identified. CONCLUSIONS AND CLINICAL IMPORTANCE: Although calcium oxalate- and struvite-containing uroliths continue to be the most common uroliths submitted from dogs, a decrease in the proportion of CaOx-containing uroliths and an increase in the proportion of cystine-containing uroliths occurred during the time period evaluated.

Urolithiasis in cats: Evaluation of trends in urolith composition and risk factors (2005-2018).

BACKGROUND: Urolithiasis is an important upper and lower urinary tract disease in cats that results in morbidity and mortality. OBJECTIVE: To describe trends in composition of uroliths in cats and evaluate risk factors related to age, breed, sex, urolith location, and bacterial urolith cultures. SAMPLE POPULATION: A total of 3940 uroliths and the cats from which they were obtained. METHODS: The database of the UC Davis Gerald V. Ling Urinary Stone Analysis Laboratory was searched for all urolith submissions from cats between January 2005 and December 2018. Mineral type, age, breed, sex, and urolith location and culture results were recorded. Trends were evaluated and variables compared to evaluate risk factors. RESULTS: A significant decrease in the proportion of calcium oxalate (CaOx)-containing uroliths occurred over time (P = .02), from 50.1% (204/407) of all submissions in 2005 to 37.7% (58/154) in 2018. In contrast, the proportion of struvite-containing uroliths increased significantly (P = .002), from 41.8% (170/407) in 2005 to 54.5% (84/154) in 2018. The proportion of CaOx-containing uroliths in the upper urinary tract was significantly higher compared to the proportion of other urolith types in the upper urinary tract. Urate-containing uroliths were the third most common type (361/3940, 9.2%). Overall, sex and age predispositions were similar to those reported previously. CONCLUSIONS AND CLINICAL IMPORTANCE: The decrease in the proportion of CaOx-containing uroliths and increase in the proportion of struvite-containing uroliths warrants investigation. Further education regarding the efficacy of medical dissolution of struvite-containing uroliths is recommended.

Removal and repositioning of urinary tract implants by use of an endovascular snare system in dogs and cats (2013-2019).

OBJECTIVE: To report the fluoroscopic removal or repositioning of urinary tract implants in dogs and cats by use of an endovascular snare system (ESS) and to report procedural usefulness and complications in dogs and cats. ANIMALS: 3 cats and 14 dogs. PROCEDURES: A medical records review was performed to identify dogs and cats that underwent removal or repositioning of urinary tract foreign bodies or implants by use of an ESS with fluoroscopic guidance at a veterinary teaching hospital from 2013 to 2019. RESULTS: Dogs had a median weight of 25 kg (55 lb) with a range of 3.5 to 60.6 kg (7.7 to 133.3 lb), and cats had a median weight of 5 kg (11 lb) with a range of 4.2 to 5.4 kg (9.2 to 11.9 lb). By use of an ESS, 12 patients (2 cats and 10 dogs) underwent transurethral retrieval of retained vesicourethral implants or ureteral stents, 2 dogs underwent transurethral ureteral stent repositioning, 1 cat and 2 dogs underwent transnephric retrieval of ureteral stents, and 1 dog underwent cystoscopic-assisted transureteral ureteral stent retrieval. All procedures were successfully performed, and there were no associated procedural complications. CONCLUSIONS AND CLINICAL RELEVANCE: Retained vesicourethral implants or ureteral stents were successfully retrieved by use of an ESS in dogs and cats transurethrally or with an open or percutaneous transnephric approach and fluoroscopic guidance. These techniques should be considered as an alternative or adjunct to more invasive methods for implant retrieval or manipulation.

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.