Preoperative parameters (signalment, digital radiography, urinalysis, urine microbiological culture) and novel algorithm improve prediction of canine urocystolith composition.

OBJECTIVE: To determine the accuracy of 4 preoperative parameters (signalment, urinalysis, urine microbiological culture, and digital radiography) in predicting urocystolith composition, compare accuracy between evaluators of varying clinical experience and a mobile application, and propose a novel algorithm to improve accuracy. ANIMALS: 175 client-owned dogs with quantitative analyses of urocystoliths between January 1, 2012, and July 31, 2020. METHODS: Prospective experimental study. Canine urocystolith cases were randomly presented to 6 blinded "stone evaluators" (rotating interns, radiologists, internists) in 3 rounds, each separated by 2 weeks: case data alone, case data with a urolith teaching lecture, and case data with a novel algorithm. Case data were also entered into the Minnesota Urolith Center mobile application. Prediction accuracy was determined by comparison to quantitative laboratory stone analysis results. RESULTS: Prediction accuracy of evaluators varied with experience when shown case data alone (accuracy, 57% to 82%) but improved with a teaching lecture (accuracy, 76% to 89%) and further improved with a novel algorithm (accuracy, 93% to 96%). Mixed stone compositions were the most incorrectly predicted type. Mobile application accuracy was 74%. CLINICAL RELEVANCE: Use of the 4 preoperative parameters resulted in variable accuracy of urocystolith composition predictions among evaluators. The proposed novel algorithm improves accuracy for all clinicians, surpassing accuracy of the mobile application, and may help guide patient management.

Pharmacokinetic study comparing doxorubicin concentrations after chemoembolization or intravenous administration in dogs with naturally occurring nonresectable hepatic carcinoma.

BACKGROUND: Chemoembolization is a viable treatment option for patients with nonresectable hepatic carcinoma (HC) and may allow delivery of chemotherapeutic drugs with decreased systemic toxicity. HYPOTHESIS/OBJECTIVE: Compare the serum concentrations of doxorubicin after chemoembolization or IV administration in the same patient. We hypothesized that locoregional delivery may result in increased tumor chemotherapeutic drug concentrations, reflected by decreased measurable serum drug concentrations. Adverse hematological events were hypothesized to be decreased after locoregional delivery. ANIMALS: Seventeen client-owned dogs with incompletely resectable HC. METHODS: Prospective, single-arm clinical trial. Drug-eluting bead transarterial chemoembolization was performed to varying levels of blood flow stasis (NO STASIS, STASIS). Intravenous doxorubicin (IVC) subsequently was administered in selected patients. Systemic exposure was quantified by area under the serum doxorubicin concentration time curve (AUC), maximum serum doxorubicin concentration (Cmax ), and time doxorubicin was last above the limit of quantitation (Tlast ). Nadir test results after treatments were used to evaluate adverse hematological events. RESULTS: Thirteen NO STASIS treatments, 15 STASIS treatments, and 9 IVC treatments were performed. Maximum serum doxorubicin concentration, AUC, and Tlast were significantly lower when comparing NO STASIS or STASIS to IVC treatments. Of the patients with nadir results available, no adverse hematological events were observed after NO STASIS or STASIS treatments. Two patients developed adverse hematological events after IVC treatment. CONCLUSIONS/CLINICAL RELEVANCE: Drug-eluting bead transarterial chemoembolization offers a viable treatment option for patients with incompletely resectable HC with the potential for increased local tumor doxorubicin concentrations, decreased systemic chemotherapeutic exposure, and fewer adverse hematological events.

Stenting of the caudal aorta and aortic trifurcation for the treatment of thrombosis in 7 dogs.

BACKGROUND: Aortic and aortoiliac thrombosis in dogs causes disease and death. OBJECTIVE: To describe the procedure and outcomes for stenting the caudal aorta and aortoiliac trifurcation. ANIMALS: Seven client-owned dogs that underwent aortic/aortoiliac stenting for treatment of thrombosis. METHODS: Retrospective multi-center investigation. Medical records were reviewed for dogs that underwent stenting of the aorta or aortoiliac trifurcation between 2008 and 2020. Information collected included history, signalment, clinicopathologic data, diagnostic imaging, procedure reports, and outcomes. RESULTS: Seven dogs with an occlusive thrombus located at or near the aortic trifurcation were included. Four of 7 dogs were non-ambulatory. Hind limbs were paretic in 5 dogs, paralyzed in 1 dog, and claudication alone was noted in 1 dog. Five of the 7 dogs had protein-losing nephropathy (PLN). Of 5 dogs with PLN, 1 had protein-losing enteropathy (PLE) and controlled hypothyroidism and 1 had caudal aortic chondrosarcoma. Two dogs had no identified underlying disease. Angiography was performed before catheter directed thrombolysis and stent placement. No deaths occurred during the procedure. Postoperative complications included pain (4/7), bruising and edema (3/7), bruising only (1/7), and edema only (1/7). Median survival time (MST) of the 7 dogs was 264 days (range, 1-1053 days). Five of 7 dogs were ambulatory within 2 days of stenting and survived to discharge with a MST of 425 days (range, 208-1053 days). CONCLUSIONS AND CLINICAL IMPORTANCE: Stenting of the aorta and aortoiliac trifurcation can provide an apparently safe and effective treatment with rapid return to ambulation for some dogs with aortic thrombosis.

Bladder wall adhesion causing a vesicular septum in a dog following surgical cystotomy.

CASE DESCRIPTION: An 8-year-old spayed female Yorkshire Terrier-Poodle dog was evaluated for persistent pollakiuria and stranguria following routine cystotomy for calcium oxalate cystoliths. CLINICAL FINDINGS: The dog presented for a cystotomy with intermittent hematuria. Postoperative radiographs revealed no remaining cystoliths. Urine, cystolith, and bladder mucosal aerobic cultures were negative. Pollakiuria, stranguria, and hematuria developed immediately after surgery and persisted despite antibiotics. Ultrasound revealed suspected fibrous adhesions within the urinary bladder lumen connecting the dorsal and ventral bladder wall creating a septum. This was confirmed cystoscopically 4 weeks after surgery. TREATMENT AND OUTCOME: Cystoscopic-guided laser ablation was performed to incise abnormal tissue connecting the ventral and dorsal bladder wall using a holmium:yttrium-aluminum-garnet laser. Three weeks later, ultrasound revealed adhesion resolution though mild pollakiuria and stranguria persisted. Oxybutynin was prescribed and clinical signs resolved. At 27 months after ablation, hematuria occurred with recurrent cystoliths. These cystoliths were removed by percutaneous cystolithotomy, documenting a cystoscopically normal bladder wall. The patient had normal urination for 55.5 months after ablation, with normal bladder wall thickness on ultrasound repeated at 27 and 36 months after ablation. CLINICAL RELEVANCE: To the authors' knowledge, an adhesion creating a septum between the dorsal and ventral bladder wall has not been previously reported as a complication after cystotomy in any species and should be considered as a cause of persistent lower urinary signs after surgery. Ultrasound identified the lesion in this dog. Because bladder abnormalities can develop quickly after surgery, ultrasound might be considered if urine testing is not supportive of infection. Cystoscopic-guided laser ablation was a successful minimally invasive treatment in this case.

Assessment of serum symmetric dimethylarginine and creatinine concentrations in cats with urethral obstruction.

OBJECTIVES: The aims of this study were to evaluate serum symmetric dimethylarginine (SDMA) and creatinine concentrations in cats with urethral obstruction pre- and post-decompression of the obstruction, and to determine if pre-decompression values were predictive of post-decompression renal function, as measured by SDMA and creatinine. METHODS: This was a prospective observational study. Twenty-five client-owned cats with urethral obstruction were hospitalized for decompression of the obstruction. Serum SDMA and creatinine were prospectively assessed at presentation, 24 h post-decompression and 5-20 days post-decompression. Urinalysis and culture were assessed at presentation and at the final follow-up. Exclusion criteria included positive urine culture, reobstruction or failure to obtain required samples. RESULTS: Mean SDMA concentration dropped by 41.8% from an initial pre-decompression concentration of 17.6 µg/dl to 10.3 µg/dl 24 h post-decompression (P <0.001). The mean creatinine value dropped by 38.4% from an initial pre-decompression concentration of 2.5 mg/dl to 1.5 mg/dl 24 h post-decompression (P <0.001). There was no association between SDMA concentration at initial presentation and SDMA concentration 5-20 days after urethral catheterization (Spearman's ρ = 0.205, P = 0.314). Creatinine concentration upon initial presentation was associated with the 5-20 day values after urethral catheterization (Spearman's ρ = 0.583, P <0.002). Twenty percent of cases were excluded due to bacterial growth on initial urine culture. SDMA and creatinine concentrations were significantly higher in these cases (median 59 µg/dl and 10.9 mg/dl, respectively) compared with those with negative cultures (median 14 µg/dl and 1.6 mg/dl [P <0.002 and P <0.001], respectively). CONCLUSIONS AND RELEVANCE: Both SDMA and creatinine decreased significantly after urethral catheterization, suggesting that renal function post-decompression cannot be predicted by the pre-decompression concentrations of these values.

Evaluation of preoperative ultrasonographic parameters to predict renal recovery in long-term survivors after treatment of feline ureteral obstructions: 2012-2019.

OBJECTIVES: The aim of this study was to determine whether preoperative ultrasound imaging characteristic(s) in cats suffering from unilateral benign ureteral obstructions are predictive of outcome after successful renal decompression with a subcutaneous ureteral bypass (SUB) device. METHODS: This was a retrospective study of 37 cats with unilateral, benign ureteral obstruction. Preoperative imaging characteristics (including renal pelvis diameter, parenchymal thickness [transverse plane], renal length and pelvic size:overall renal size) and biochemical data were evaluated for all cats diagnosed with a unilateral ureteral obstruction treated with a SUB device. Any patient with bilateral obstructions or documented bacteriuria/infection in the data collection period was excluded. All patients were followed between 3 and 6 months postoperatively to obtain postoperative biochemical data. Long-term outcome was defined as serum creatinine concentration at 3-6 months postoperatively. RESULTS: No preoperative imaging characteristics or biochemical findings were found to be significantly associated with long-term serum creatinine concentrations. The length of the kidney was found to be associated with change in blood urea nitrogen and creatinine with decompression but not with long-term renal values. CONCLUSIONS AND RELEVANCE: In this study, long-term renal function based on preoperative ultrasound imaging findings could not be predicted in cats with unilateral ureteral obstruction, regardless of the severity of the biochemical parameters, renal pelvic dilation (large or small pelvis), kidney size or thickness of renal parenchyma assessed.

Drug-eluting bead chemoembolization for the treatment of nonresectable hepatic carcinoma in dogs: A prospective clinical trial.

BACKGROUND: Effective treatment options for nonresectable hepatic carcinoma (HC) in dogs are limited. HYPOTHESIS/OBJECTIVE: Objectives were to report outcomes, complications, and tumor responses via computed tomography (CT) assessment after drug-eluting bead transarterial chemoembolization (DEB-TACE) for nonresectable HC in dogs. The authors hypothesized that major complications would be uncommon and short-term CT assessment would demonstrate stable disease or partial response. ANIMALS: Client-owned dogs (n = 16) with nonresectable HC. METHODS: Prospective, single-arm clinical trial. Drug-eluting bead transarterial chemoembolization was performed to varying levels of blood flow stasis. Computed tomography imaging was compared before and approximately 12 weeks after initial treatment. RESULTS: Drug-eluting bead transarterial chemoembolization was successfully administered in all attempts. Based on percent change in elliptical tumor volume response (mL), stable disease (8/13; 62%) was the most common outcome followed by partial response (3/13; 23%) and progressive disease (2/13; 15%) with a median of 74 days (range, 39-125) after initial treatment. Median tumor volume (mL) after DEB-TACE decreased in volume by 13% (range, 56% decrease to 77% increase). Mild complications consistent with postembolization syndrome occurred after 7/27 (26%) treatments. Major complications occurred after 3/27 (11%) treatments: hepatic abscess/septicemia (2) and cholecystitis/death (1), resulting in treatment-induced death after 2/27 (7%) treatments. Median survival time after treatment was 337 days (range, 22-1061). Dogs with a presenting complaint of weight loss (P = .02) had a significantly shorter median survival time (126 days; range, 46-337) than those dogs without prior history of weight loss (582 days; range, 22-1061). CONCLUSIONS: Drug-eluting bead transarterial chemoembolization for nonresectable HC is a feasible procedure, which promoted stable disease or partial response in 85% of dogs in this study sample.

Use of tissue plasminogen activator to alleviate postoperative subcutaneous ureteral bypass obstruction secondary to blood clot in seven cats.

CASE SERIES SUMMARY: Seven cats were found to have postoperative subcutaneous ureteral bypass (SUB) occlusion secondary to blood clot formation. An increase in serum creatinine led to imaging and clot detection in all but one case. Alteplase, a tissue plasminogen activator, was infused into the SUB via the port in four cats, intravesicularly via a transurethral urinary catheter in one cat, and by both routes in two cats. Patency of the SUB was re-established in all cats within 2 days. No short- or long-term complications directly attributed to alteplase administration were observed. RELEVANCE AND NOVEL INFORMATION: The results of this case series suggest that alteplase infusion via either the SUB port and/or a transurethral catheter should be considered prior to surgical intervention for the treatment of postoperative SUB occlusion secondary to a blood clot.

Comparison of short-, intermediate-, and long-term results between dogs with tracheal collapse that underwent multimodal medical management alone and those that underwent tracheal endoluminal stent placement.

OBJECTIVE: To compare short-, intermediate-, and long-term results between dogs with tracheal collapse (TC) that received multimodal medical management only and those that underwent tracheal endoluminal stent placement. ANIMALS: 159 dogs with TC that underwent medical management only (MM group; n = 84) or were surgically managed by stent placement (SM group; 75). PROCEDURES: Medical records of dogs with TC that underwent medical management only or stent placement at a referral hospital between September 1, 2009, and August 1, 2018, were reviewed. Data regarding signalment, information relevant to TC, and outcome were extracted from the records and aggregated into short-, intermediate-, and long-term follow-up periods for analysis. Descriptive data and median survival times (MSTs) were compared between the MM and SM groups. RESULTS: Clinical signs of dogs in the MM group generally improved during the short term but regressed and worsened over time. The proportion of dogs with malformation-type TC that underwent stent placement (38/43 [88%]) was significantly greater than the proportion of dogs with traditional-type TC that underwent stent placement (37/107 [35%]). The MST from TC diagnosis was 3.7 years for the MM group and 5.2 years for the SM group. For dogs with severe disease, the MST was 12 days for medically managed dogs and 1,338 days for dogs that underwent stent placement. CONCLUSIONS AND CLINICAL RELEVANCE: Multimodal medical management alleviated clinical signs for months to years in dogs with mild to moderate TC disease, but stent placement should be considered for dogs with severe disease.

Retrospective study of proliferative urethritis in dogs: Clinical presentation and outcome using various treatment modalities in 11 dogs.

BACKGROUND: Proliferative urethritis (PU) is an uncommon inflammatory and infiltrative disease of the urethra in female dogs, often associated with urinary tract infection (UTI). It typically presents with evidence of urethral obstruction (UO). OBJECTIVES: Identify clinical features in dogs with PU and determine outcome after different treatment modalities. ANIMALS: Eleven client-owned dogs. METHODS: Medical records of dogs with histopathologic diagnosis of PU from 2011 to 2020 were retrospectively evaluated, including information on clinical pathology, imaging, and histopathology. Outcomes of various treatment modalities were recorded and compared. Long-term urethral patency (>6 months) was considered treatment success. RESULTS: All dogs were female and presented with UO. Eight (73%) had a history of UTI. Ten of 11 survived to discharge and were used for long-term data collection. Seven of 10 (70%) were treated using an effacement procedure (balloon dilatation [BD], stent, or both) and 6/7 (86%) achieved long-term urethral patency (>6 months). Seven of 10 had UO recurrence after their first procedure, including 3/3 (100%) that did not have effacement and 4/7 that did (57%), at a median of 101 days and 687 days, respectively. After effacement, the duration of patency was longer for those treated using a stent than BD alone (median, 843 days and 452 days, respectively). CONCLUSIONS AND CLINICAL IMPORTANCE: Proliferative urethritis is a recurrent disease often associated with UTI. The best outcome of long-term urethral patency occurred after lesion effacement, either by BD or stenting. Future prospective studies should determine the impact of immunosuppressive treatment.

Transatrial stenting for long-term management of cardiac tumor obstruction of the right atrium in 3 dogs.

BACKGROUND: Venous obstruction in dogs caused by large intracardiac masses can result in severe morbidity with few safe treatments. HYPOTHESIS/OBJECTIVES: Retrospective study to report results after transatrial stent placement in dogs with naturally occurring cardiac masses causing venous obstruction. ANIMALS: Three client-owned dogs diagnosed with large cardiac masses. METHODS: Retrospective study of patients that received transatrial stents extending from the caudal vena cava, across the right atrium, and into the cranial vena cava (CrVC). Procedures, complications, and outcomes were recorded based upon medical records, referring veterinarians, and client communications. RESULTS: Two dogs had similar clinical signs suggestive of congestive hepatopathy including marked ascites and lethargy. One dog had clinical signs of CrVC syndrome including head and neck swelling with pitting edema and pleural effusion. After stent placement, venous pressure gradients were decreased and repeat angiography confirmed that vascular patency was reestablished. Resolution of clinical signs was marked in all 3 dogs with only mild complications including tachyarrhythmias and hypertension in 1 dog during the perioperative period. Two dogs that required additional transatrial stent placement for reobstruction 6 and 14 months later improved after the second stent implantation. Survival times poststenting for the dogs were 3, 21, and 37 months, with cause of death related to the cardiac tumor in all dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: Endovascular transatrial stenting may provide a long-term palliative treatment option for dogs with clinical signs attributable to tumor-induced venous obstruction when more traditional treatments are declined or not indicated.

Use of percutaneous foam sclerotherapy with 1.5% sodium tetradecyl sulfate for treatment of a pelvic limb venous malformation in a dog.

CASE DESCRIPTION: A 6-year-old 17-kg (37.4-lb) spayed female mixed-breed dog was evaluated because of swelling and intermittent lameness of the right pelvic limb and perianal and vulvar bleeding caused by a suspected arteriovenous malformation. CLINICAL FINDINGS: The right pelvic limb had a diffuse, raised, cobblestone-like appearance with lameness, edema, and multifocal ulcerations. The abdominal skin had multifocal circular erythematous lesions, the perianal region was erythematous, and the vestibule had superficial distended vessels. Ultrasonography and CT did not reveal the presence of an arteriovenous malformation; however, digital subtraction venography confirmed the presence of a venous malformation (VM) throughout the limb. TREATMENT AND OUTCOME: A mixture of foam sclerosant (1.5% sodium tetradecyl sulfate) and contrast medium was agitated with air and injected percutaneously into the VM. The dog received an injection of corticosteroid solution, and a soft-padded bandage was applied to the limb for 3 days. Six weeks later, the dog would intermittently hop when running, and the limb was mildly edematous with ecchymotic lesions; the swelling and lameness had improved considerably. Perianal and vulvar bleeding and dilation of the vestibular vessels had resolved. At 21 months after the procedure, examination revealed no right pelvic limb lameness related to the VM; only small cyst-like lesions and edema around the tarsus remained. CLINICAL RELEVANCE: The favorable clinical outcome for this dog for a 21-month period after treatment of a pelvic limb VM with foam sclerotherapy has suggested that foam sclerotherapy may be used to successfully treat limb VMs in some dogs.

Radiographic features of suspected suture-associated cystic calculi in dogs.

This retrospective case series describes the radiographic features of suspected suture-associated cystic calculi in six dogs with a history of at least one or multiple prior cystotomies. One of the dogs presented twice. Suspected suture-associated cystic calculi were multifocal, short, predominantly linear mineral opacities localized in the center of the urinary bladder on abdominal radiographs. One patient (n = 1) presented with multifocal round, pin point, and linear radiopaque calculi. The calculi were all calcium oxalate in composition. On gross examination, the calculi had a hollow center. Six cystotomies used monofilament absorbable suture material (polydioxanone [n = 4] or poliglecaprone 25 [n = 1]) in prior cystotomies. Suture material in two of the cases was unknown. Suspected suture-associated cystic calculi are a rare occurrence in veterinary medicine but should be considered in dogs that have a history of prior cystotomy, hollow core on gross analysis, and radiographic evidence of mineral opaque, predominantly linear, cystic calculi.

Therapeutic use of tetrasodium ethylenediaminetetraacetic acid solution for treatment of subcutaneous ureteral bypass device mineralization in cats.

BACKGROUND: Subcutaneous ureteral bypass (SUB) device placement is an increasingly popular treatment option for decompression of ureteral obstruction in cats. Mineralization occlusion of the device occurs in a minority of cases but is the most common complication. OBJECTIVE: To evaluate a 2% tetrasodium ethylenediaminetetraacetic acid (tEDTA) solution for treatment of mineralization occlusion in cats with SUBs. ANIMALS: Six client-owned cats (8 obstructed devices). METHODS: Case series. Each cat was found to have device occlusion based on a combination of ultrasound examination, SUB irrigation, and failure to identify another cause of device obstruction. Each SUB was drained, irrigated using sterile saline, and infused with 1-2 mL of 2% tEDTA solution. Success was defined as normalization of flow during subsequent ultrasound visualization while irrigating. The volume and frequency of tEDTA instillations, time to achieve device patency, follow-up biochemical and ultrasound findings, and future reobstruction events were recorded. RESULTS: Resolution of mineralization was documented in all 8 SUBs. Reobstruction events occurred in 2 cats, all of which resolved after additional tEDTA infusions, but 1 cat ultimately required device exchange at 356 days from the first tEDTA infusion. In 1 cat, a single infusion was prematurely discontinued because of persistent pelvic dilatation after 1.25 mL of tEDTA had been instilled. No complications were observed. CONCLUSIONS AND CLINICAL IMPORTANCE: Tetrasodium EDTA infusions can be safely considered as a treatment option for mineralized SUB devices in cats. This solution was easily infused, well tolerated, and avoided the need for SUB device exchange in the majority of cats in which it was used.

Correlations among tracheal dimensions, tracheal stent dimensions, and major complications after endoluminal stenting of tracheal collapse syndrome in dogs.

BACKGROUND: Endoluminal tracheal stenting can relieve signs associated with tracheal collapse syndrome (TCS) in dogs, but major complications can result. OBJECTIVE: To identify associations among tracheal dimensions, stent dimensions, and subsequent complications requiring additional stent placement after endoluminal stenting for TCS. ANIMALS: Fifty-two dogs from the hospital population. METHODS: Medical records of dogs that received an endoluminal self-expanding tracheal stent for TCS by the interventional radiology service between 2009 and 2014 were reviewed for relevant data. Signalment and clinical details, including tracheal collapse type, tracheal measurements, nominal stent dimensions, follow-up evaluation times, and stent complications, were recorded. RESULTS: Fifty-two dogs that received an endoluminal stent for TCS met the inclusion criteria. Major complications included stent fracture (13/52; 25%), obstructive tissue ingrowth (10/52; 19%), and progressive tracheal collapse (6/52; 12%). Natural tracheal taper (P = .04) and more stent diameter oversizing (P = .04) in the intrathoracic (IT) trachea were associated with caudodorsal stent fracture. Only stents with a 14-mm nominal diameter fractured. Progressive tracheal collapse was associated with smaller maximum tracheal diameters (P = .02). The majority of dogs with obstructive tissue ingrowth (7/10; 70%; P = .30) and all dogs with thoracic inlet fractures (3/3; 100%) had tracheal malformations. CONCLUSIONS AND CLINICAL IMPORTANCE: A higher taper in tracheal diameter may lead to increased risk of fracture in the IT location. Dogs with tracheal malformations may have higher risk for thoracic inlet fracture and development of obstructive tissue ingrowth. Clinicians should be aware of the possible risk factors for tracheal stent complications.

Endoscopic nephrolithotomy for the removal of complicated nephroliths in dogs and cats: 16 kidneys in 12 patients (2005-2017).

OBJECTIVE: To describe techniques and outcomes for dogs and cats undergoing endoscopic nephrolithotomy (ENL) for the removal of complicated nephroliths. ANIMALS: 11 dogs and 1 cat (n = 16 renal units) with complicated nephroliths that underwent ENL via a surgically assisted ENL approach (12 renal units) or a percutaneous nephrolithotomy approach (4 renal units) between December 2005 and June 2017. PROCEDURES: Data were obtained from the medical records regarding preoperative, operative, and postoperative findings. Follow-up information on complications and outcomes was also collected. RESULTS: Indications for nephrolith removal included massive calculi displacing parenchyma (n = 7), recurrent urinary tract infections (5), and ureteral outflow obstruction (4). Median nephrolith diameter was 2.5 cm (range, 0.5 to 5.7 cm). Nephrolith composition differed among patients; calcium oxalate was the most common type (n = 7 [including 2 mixed nephroliths containing ≥ 60% calcium oxalate]). Following ENL (median duration, 180 minutes), 15 of 16 renal units were completely nephrolith free. Procedure-related complications included renal puncture-associated hemorrhage requiring a blood transfusion (n = 1), renal capsule tear (1), and ureteral puncture (1); all were managed without adverse consequence. Five of 12 patients remained alive at the final follow-up (median, 557 days after ENL), and none died from the procedure. CONCLUSIONS AND CLINICAL RELEVANCE: ENL as performed was safe and effective in removing complicated nephroliths in a renal-sparing manner for the patients in this study. This procedure requires technical training and could be considered for the treatment of complicated nephrolithiasis in dogs and possibly cats.

Vesicovaginal fistula in a dog with urinary incontinence.

CASE DESCRIPTION: A 5-year-old spayed female Maltese mixed-breed dog was referred for evaluation because of severe urinary incontinence refractory to medical management. CLINICAL FINDINGS: Physical examination revealed constant dribbling of urine and urine scalding. Culture of a urine sample yielded methicillin-resistant Staphylococcus pseudintermedius and Proteus mirabilis. Abdominal ultrasonographic examination revealed absence of the left kidney, a small, nondistended urinary bladder, and diffuse hepatopathy. Urinary incontinence persisted despite appropriate antimicrobial treatment. Cystourethroscopy and vaginoscopy were subsequently performed and revealed a hypoplastic bladder and a vesicovaginal fistula with urinary leakage through the vaginal diverticulum; no left ureterovesicular junction was identified, consistent with suspected left renal aplasia. TREATMENT AND OUTCOME: Exploratory laparotomy was performed, and the cranial aspect of the vagina was circumferentially ligated immediately caudal to the fistula. The urinary incontinence resolved immediately after surgery, and lower urinary tract signs improved over the next 2 weeks. Moderate urinary incontinence recurred approximately 6 months later, and a urinary tract infection with Escherichia coli was subsequently identified and treated; clinical signs resolved ≤ 48 hours after treatment was initiated. CLINICAL RELEVANCE: To the author's knowledge, vesicovaginal fistulas in dogs have not been previously described and should be considered a differential diagnosis for persistent urinary incontinence and recurrent urinary tract infections in female dogs. Vaginoscopy in addition to cystourethroscopy was required to identify the abnormality in this patient. Because multiple concurrent anomalies can be present, both procedures should be performed in female dogs with these clinical signs, even if an abnormality is identified cystoscopically.

Use of cystoscopy or cystourethroscopy in treating benign macroscopic hematuria caused by lower urinary tract hemorrhage in three dogs.

CASE DESCRIPTION: A 5-year-old 11.5-kg (25.3-lb) castrated male Boston Terrier (dog 1), an 8-year-old 27.8-kg (61.2-lb) castrated male Boxer (dog 2), and a 10.5-year-old 15.9-kg (35.0-lb) spayed female Pembroke Welsh Corgi (dog 3) were evaluated because of severe, gross hematuria and suspected idiopathic renal hematuria. CLINICAL FINDINGS: All 3 dogs had hematuria, anemia, blood clots in their urinary bladders, and unremarkable findings on coagulation and mucosal bleeding time assessments. With cystourethroscopy, lower urinary tract hemorrhage originating from a small lesion in the urinary bladder (n = 2) or urethra (1) and normal-appearing yellow urine jetting from both ureterovesicular junctions were visualized in each dog. TREATMENT AND OUTCOME: Cystoscopically guided surgical resection of a hemorrhagic lesion of the urinary bladder was performed on dog 1, and histologic evaluation of the resected tissue confirmed urinary bladder telangiectasia. Dogs 2 and 3 each underwent cystourethroscopically guided laser ablation of a hemorrhagic lesion (presumptively diagnosed as hemangioma, angioma, or telangiectasia) in the urinary bladder (dog 2) or urethra (dog 3). The longest follow-up duration was 7 years, and none of the 3 dogs had subsequent recurrence of gross hematuria. CLINICAL RELEVANCE: Findings suggested that cystourethroscopy should be considered part of the diagnostic plan for hematuria in dogs before pursuing major surgical treatment or when results of conventional diagnostic procedures do not indicate the underlying cause. In addition, histologic results for dog 1 indicated urinary bladder telangiectasia, previously an unreported cause of severe, chronic lower urinary tract hematuria in dogs.

Intra-arterial renal infusion of autologous mesenchymal stem cells for treatment of chronic kidney disease in cats: Phase I clinical trial.

BACKGROUND: There are no known treatments that halt or reverse chronic kidney disease (CKD) in cats. In rodent models, stem cell treatment has been associated with improvement in renal function parameters, especially when stem cells were delivered intra-arterially to the kidney. To date, only IV and intrarenal stem cell infusions have been studied in cats with CKD with no clinically relevant improvement noted. OBJECTIVE: To assess the safety and feasibility of intra-arterial delivery of autologous mesenchymal stem cells (MSC) in stromal vascular fraction (SVF) to the kidney in cats with CKD. ANIMALS: Five client-owned domestic cats with International Renal Interest Society stage III CKD. METHODS: Prospective cohort study (phase I clinical trial). Adipose tissue was harvested from study animals on day 0. On days 2 and 14, an infusion of MSC in SVF was administered into the renal artery via the femoral or carotid artery using fluoroscopic guidance. Serum creatinine and blood urea nitrogen concentration, plasma iohexol clearance, and quality of life assessments were monitored between days 0 and 90. RESULTS: The procedure was performed successfully in all cats. No severe adverse events were observed in any cat during the study period. CONCLUSIONS AND CLINICAL IMPORTANCE: Intra-arterial infusion of MSC into the renal artery in CKD cats was feasible and safe within a 3-month postoperative period. Efficacy and long-term safety have yet to be established. This procedure requires careful technique and training.

Endoscopic laser-ablation for the treatment of orthotopic and ectopic ureteroceles in dogs: 13 cases (2008-2017).

BACKGROUND: Ureteroceles are a rare condition in dogs in which conventional treatments can result in substantial morbidity. Cystoscopic and fluoroscopic-guided laser ablation (CLA) of ureteroceles can successfully relieve obstruction. OBJECTIVES: To describe the technique and outcomes of attempting CLA for treatment of ureteroceles in dogs. ANIMALS: Thirteen client-owned dogs that underwent CLA for treatment of ureteroceles. METHODS: Retrospective multicentered study. Medical records were reviewed in all dogs that underwent CLA for ureterocele(s). A laser was used to extend the opening of the ureteral orifice (UO) unless surgical conversion was necessary. Data collected included signalment, clinicopathologic data, imaging, procedural findings, complications, and short- and long-term outcome. RESULTS: Thirteen dogs with 13 ureteroceles associated with 14 UOs resulting in ureteral obstruction were included. One ureterocele extended bilaterally. Treatment was initiated via retrograde cystoscopy (7 females), percutaneous perineal urethrocystoscopy (4 males), or percutaneous antegrade cystoscopy (2 males). Surgical conversion was necessary in 2 males. Ten of 14 (71%) UOs associated with the ureteroceles were ectopic. Thirteen of 14 had stenotic or imperforate UOs. No postoperative complications were noted. Preoperative incontinence or pollakiuria was present in 9 of 13 and 3 of 13 dogs and resolved in 8 of 9 and 3 of 3 dogs, respectively. Follow-up imaging showed resolution of all ureteroceles and improved ureteral/renal pelvic dilatation. Median follow-up time was 27 months (range, 3-96 months). CONCLUSIONS AND CLINICAL IMPORTANCE: Cystoscopic-guided laser ablation was effective for the treatment of ureteroceles(s) in 11 of 13 dogs.