Congenital Diseases of the Lower Urinary Tract

Renal Agenesis, Extramural Ectopic Ureter, and Nonfunctioning Urinary Bladder: A Difficult Clinical Case with an Innovative Approach

Summary. A 7-month-old female Jack Russell Terrier weighing 4.6 kg was referred to a veterinary hospital for persistent urinary incontinence. Blood test results and vital signs were within the normal range. Computed tomography allowed the diagnosis of extramural ectopic ureter and unilateral renal agenesis. After the first neoureterocystostomy surgery, the dog had severe complications, such as hydroureter and hydronephrosis, so a second surgery was performed. A commercial ureteral stent was not an option, and it was decided to fabricate a homemade stent to avoid euthanasia. The stent used was a soft, DEHP-free PVC tube with a lumen of 3 × 4.1 mm and a length of approximately 40 mm that connected the ureter to the urinary bladder. Two years after surgery, the dog is in good general condition, and the results of regularly performed blood and urine tests are within the normal range for dogs.

Cystoscopic Guided Laser Cauterization in a Dog with Complete Y-Type Urethral Duplication

Duplication of the urethra is a rare congenital malformation. A 14-month-old, sexually intact, male, Lagotto dog with complete Y-type urethral duplication was subjected to accessory urethra treatment for cystoscopic guided laser cauterization, with a 10-Watt diode laser with 550-micron fiber and 2.3 Fr outer diameter. The laser cauterization, that was repeated every 14 days for a total of three times, was performed by inserting the instrument from the accessory urethra outlet in the perianal area until it could be seen by the urethroscope, inside the ischial urethra. Nevertheless, this technique that proved to be non-invasive, less expensive than surgery, of short duration, and safe, did not allow the complete closure of the abnormal urethral tract. Therefore, the subsequent surgical removal of the accessory urethra was carried out. To the authors' knowledge this is the first report on the use of cystoscopic guided diode laser cauterization for accessory urethra treatment.

Ultrasonographic detection of apex nodules in the urinary bladder of Scottish Terriers

An apex nodule was recently identified in the urinary bladder of Scottish Terriers being screened for bladder cancer at our institution. This prospective, single-center, case series study was performed to better characterize the apex nodule and assess the clinical importance of the nodule. Scottish Terriers ≥6 years of age with no evidence of urinary tract disease underwent urinary tract ultrasonography and urinalysis at 6-month intervals. In dogs with evidence of the apex nodule, ultrasound features such as location, margins, number, echogenicity, size, and shape of the lesion were recorded by a veterinary oncologist and veterinary radiologist. The apex nodule was identified in eight (6%) of 134 dogs in the absence of other detectable bladder disease. Features of the nodules included the following: one nodule per dog, triangular to an oval shape, smooth mucosal covering, well-defined margins, isoechoic to the bladder wall, 2-4 mm at the base, and 4-6 mm protruding into the bladder lumen. In five dogs undergoing multiple ultrasonographic examinations, the nodule did not appear to change over time (up to 3.5 years). Cystoscopy performed in three dogs revealed a column of tissue covered by normal mucosa protruding into the bladder lumen. Histological features consistent with a neoplastic growth were absent. Five dogs remained free of any bladder disease. Three dogs developed urothelial carcinoma at sites distant to the nodule at 8-53 months after the nodule was first observed. Findings indicated that incidental apex nodules could mimic neoplasia and other bladder diseases in Scottish Terriers.

Feline urinary incontinence: a retrospective case series (2009-2019)

OBJECTIVES

The objective of this retrospective study was to describe the feline population presented for urinary incontinence at a veterinary teaching hospital between 2009 and 2019, with a particular focus on cats with a non-neurologic underlying cause.

METHODS

The medical records of cats diagnosed with urinary incontinence were retrospectively evaluated. Signalment, clinical presentation, results of diagnostic tests, diagnosis of the underlying cause and treatments were recorded. When information was available, outcome was recorded and follow-ups divided into three time frames (0-1 week, 1 week to 3 months and >3 months).

RESULTS

Thirty-five cats were presented with urinary incontinence. Of these, 18 cats with complete medical records presented urinary incontinence of non-neurologic origin. The most common clinical signs at presentation were urine leakage while resting (12/18), urine-soiled perineum (8/18), urine dribbling (8/18) and no spontaneous micturition (5/18). The most common underlying cause was urethral obstruction (67%; 12/18), with a majority due to urethral strictures (58%; 7/12). Other causes were suspected inflammation (2/12), neoplasia (1/12), urolithiasis (1/12) and foreign body (1/12). In 8/10 cats in which it was performed, cystoscopy and contrast cystourethrography were the methods that led to the diagnosis. Twelve cats with urethral obstruction underwent interventional procedures, resulting in complete resolution of incontinence in 7/12 and improvement in 1/12. Urinary tract infection was a common complication after 3 months (4/18).

CONCLUSIONS AND RELEVANCE

When incontinence of non-neurologic origin is suspected in a cat, urethral obstruction should be considered. Advanced imaging studies (cystoscopy and contrast studies) are useful for diagnosis. A good prognosis was reported in cats undergoing interventional procedures with no long-term treatment.

Ultrasonographic Diagnosis of Urachal Anomalies in Cats and Dogs: Retrospective Study of 98 Cases (2009-2019)

This retrospective study investigated the prevalence of different urachal anomalies (UA) in cats (n = 60) and dogs (n = 38) and their association with clinical symptoms and urinalysis alterations. Among UA, the vesicourachal diverticulum was the most prevalent UA diagnosed in both cats (96.7%) and dogs (89.5%): the intramural vesicourachal diverticulum was diagnosed in 76.7% of cats and 71.1% of dogs, followed by extramural vesicourachal diverticulum (20.0% and 18.4% respectively). In both cats and dogs, bladder wall diffuse or regional thickening was the most prevalent alteration. The most common alterations of the urinary bladder content were urolithiasis sediment in cats (33.3%) and in dogs (31.6%). Dogs with UA were more often asymptomatic (p = 0.01). No difference was found in cats. Stranguria, hematuria, and urethral obstruction were the most frequently reported clinical signs, while hematuria and leukocyturia were the most prevalent abnormalities at urinalysis. In conclusion, our study confirmed UA as uncommon, and often incidental findings, with a high prevalence of animals without clinical signs.

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.

Contrast-enhanced voiding urosonography: A new, radiation-free, alternative method for imaging of urinary bladder and urethra in healthy dogs

Contrast-enhanced voiding urosonography (CE-VUS) has been generally considered as a promising tool to diagnose vesicoureteral reflux and abnormalities in lower urinary tract in human patients, especially in children. The purpose of this prospective study is to evaluate the quality of images of the urinary bladder and urethra obtained by CE-VUS using a second-generation ultrasound contrast agent (SonoVue®) in healthy dogs and to investigate the safety profile of SonoVue® after intravesical administration. Eighty-four CE-VUS examinations with SonoVue® were successfully performed in both unsedated (39/84) and sedated (45/84) dogs. Contrast-enhanced voiding urosonography examination of urinary bladder was technically successful in all (84/84) dogs. The image quality was not considered adequate in five (5/84) dogs including three dogs in whom layering of contrast media during filling phase was observed and two dogs with premature destruction of microbubbles. In these five dogs, the problem was readily recognized and corrected such that the procedure was still successfully undertaken. The assessment of the urethra during spontaneous micturition was successfully performed in all (84/84) dogs in whom voiding was elicited during the examination. No side effects were observed after intravesical application of SonoVue®. This study demonstrates that CE-VUS is a feasible and valuable technique to evaluate low urinary tract morphology and function in dogs. Based on our review of the literature, there are no published reports about the use of this method in dogs.

Urethral obstruction and urolithiasis associated with patent urachus in a 12-week-old kitten

Case summary

A 12-week-old intact male domestic shorthair kitten presented for dysuria. The patient had a urethral obstruction that was relieved with urinary catheter placement. A cutaneous opening at the umbilicus was identified. Three-view abdominal radiographs and a contrast study revealed a patent urachus with no evidence of urine leakage into the abdomen. An exploratory laparotomy was performed that confirmed a patent urachus, which was excised, and cystic and urethral calculi, which were removed via cystotomy. The patient recovered well from surgery, with a 12 h period of stranguria occurring 2 days postoperatively, attributed to residual inflammation. Calculi analysis revealed struvite stones, likely secondary to infection and inflammation. At the time of writing, 3 months postoperatively, the kitten had one episode of hematuria and inappropriate urination, which resolved with a short course of non-steroidal anti-inflammatory drugs, but had been otherwise been asymptomatic and healthy.

Relevance and novel information

To our knowledge, this is the first report of urolithiasis and patent urachus in a pediatric feline patient. Based on the occurrence of struvite stones in the presence of a patent urachus in an animal of this age, we suspect that chronic infection and inflammation led to the development of urolithiasis. Correction of the patent urachus resulted in almost complete resolution of clinical signs and no crystal formation was appreciated on recheck urinalysis.

Retrospective analysis of diagnoses and outcomes of 45 cats with micturition disorders presenting as urinary incontinence

Background

In contrast to dogs, the causes and outcomes of urinary incontinence (UI) in cats are largely unknown.

Objectives

To determine the causes, identify comorbid conditions, and assess outcomes of cats with micturition disorders presenting as UI.

Animals

Forty‐five cats with UI.

Methods

Retrospective study. Medical records of cats presented from January 2006 to December 2017 were searched using 45 keywords related to UI. History, presenting complaint, and physical examination findings were used to confirm a diagnosis. Cases were categorized based on functional and anatomic localizations.

Results

Forty‐five cats met inclusion criteria. Spinal cord disease was the most common cause of UI (n = 18), followed by urethral (n = 17), bladder (n = 9), and ureteral (n = 1) disorders. Proportions of voiding and storage phase disorders were similar (53% and 47%, respectively). However, voiding‐phase disorders were observed more frequently in males and younger‐aged cats (P < .03). Urinary tract infection was detected in 11 of 28 (39%) cats. Outcomes were available in 38/45 cases; 16 cats (42%) regained continence, 3 (8%) improved with treatment, and 19 (50%) remained incontinent or were euthanized. Multiple variable logistic regressions indicated that spinal cord disease was significantly more likely to be associated with poor outcomes compared to bladder or urethral disorders (P < .04).

Conclusions and Clinical Importance

Urinary incontinence in cats was associated with a variety of congenital and acquired disorders that affected both phases of micturition with similar frequency. Incontinent cats with spinal cord disorders were common and warrant a more guarded prognosis than do cats with bladder or urethral disorders.

Urethral prolapse corrected by microsurgery in a cat: a case report

Urethral prolapse is a rare condition in dogs and cats. A 7-month-old male cat presented with intermittent penile bleeding and a red mass protruding from the tip of the penis. Urethral prolapse was diagnosed by using a surgical microcamera to examine the genital area. Urethroplasty and preputial advancement surgery were performed using a surgical microscope, to successfully correct the urethral prolapse.