Vaginourethroplasty for treatment of urethral obstruction in the bitch

Novel surgical approach to neoplastic lesions in the distal part of the urethra: A pilot cadaver study comparing open and hybrid techniques

Tumours of the distal urethra in female dogs are often difficult to treat, and the surgical methods described thus far have technical limitations. This study aimed to present a novel approach to the surgical treatment of distal urethral tumours. This study used dog cadavers to evaluate the technical feasibility of surgically removing neoplastic lesions in the distal urethra and compared surgical outcomes of open surgery with those of hybrid surgery (combination of laparoscopy and open surgery). Open intact, open spayed, hybrid intact, and hybrid spayed dog cadaver groups underwent surgery (n = 6 per group). The novel surgical method was based on vulvovaginectomy (ovariohysterectomy in intact dogs), resection of the distal part of the urethra, and pre-pubic urethrostomy. Outcomes of interest included technical feasibility of each procedure, using both surgical techniques, wound length, time required to complete the procedure, and the incidence of intraoperative ureter and rectum injuries. Surgical technique and reproductive status affected operating time. Technique choice affected wound length; the surgical wound was longer in the open group than in the hybrid group. Macroscopic evaluation of the rectum did not reveal any damage to the wall. There was no evidence of ureter leakage or obstruction in any case. The present findings suggest that both open and hybrid surgery can be used to treat distal urethral tumours.

Case report laparoscopy-assisted pre-pubic urethrostomy as a palliative procedure for resection of distal urethral tumor in a female dog

Background

This paper presents the first described case of laparoscopy-assisted prepubic urethrostomy and laparoscopic resection of a tumor of the distal part of the urethra in a female dog as a palliative treatment.

Case presentation

An intact, 11 -year-old, mixed breed female dog, weighing 15 kg, was admitted with signs of urinary obstruction and difficulty with catheterization. Vaginal, rectal, and endoscopic examinations revealed a firm mass in the pelvic cavity at the level of the pelvic urethra. Ultrasound and computed tomography examination showed enlargement of the urethral wall (5.5 cm width and 3 cm thick), which was significantly restricting the patency of the urethra. The lesion affected only the distal part of the urethra without the presence of local or distant metastatic changes.

The affected portion of the urethra was laparoscopically removed while performing pre-pubic urethrostomy with laparoscopy. The patient regained full consciousness immediately after the end of anesthesia, without signs of urinary incontinence. Histopathological examination of the removed urethra revealed an oncological margin only from the side of the bladder. In the period of 2.5 months after the procedure, the owner did not notice any symptoms that could indicate a postoperative recurrence, which was diagnosed three months after the procedure.

Conclusions

Pre-pubic urethrostomy can be successfully performed with the assistance of laparoscopy. The use of minimally invasive surgery will allow, in selected cases, removal of the urethral tumor, and in inoperable cases, to perform a minimally invasive palliative pre-pubic urethrostomy.

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.

Outcomes associated with vaginectomy and vulvovaginectomy in 21 dogs

OBJECTIVE

To report the outcomes of dogs with lesions of the genitourinary tract treated by vaginectomy or vulvovaginectomy.

STUDY DESIGN

Multi-institutional retrospective study.

ANIMALS

Female dogs that underwent vulvovaginectomy, complete vaginectomy, or subtotal vaginectomy from 2003 to 2018 with complete medical records and a minimum of 60 days follow-up.

METHODS

Data collected from medical records included preoperative, intraoperative, and postoperative data, such as the occurrence of urinary incontinence (UIC), disease recurrence, and death/euthanasia.

RESULTS

This study included 21 dogs. Four dogs had vulvovaginectomy, six had complete vaginectomy, and 11 had a subtotal vaginectomy performed. The mean age at surgery was 9.2 years (SD, 3.3). Thirteen dogs were intact at presentation. Smooth muscle tumors were diagnosed most commonly (10 leiomyomata, three leiomyosarcomas, two leiomyofibromas). The median duration of follow-up was 520 days (range, 71-1955). Major complications requiring revision surgery were recorded in two dogs. Postoperative UIC occurred in six of 21 dogs, resolving spontaneously within 60 days in three dogs. Dogs with malignant tumors (n = 6) survived at least 71 days (median, 626; 95% CI, 71-1245), and recurrence of disease occurred in two dogs. In dogs with benign tumors (n = 15), the median survival time was not reached. These dogs survived at least 104 days and had no recurrence of the disease.

CONCLUSION

Vaginectomy and vulvovaginectomy resulted in prolonged survival and low rates of major complications and UIC.

CLINICAL SIGNIFICANCE

This study provides evidence to recommend that the risks of this procedure and expectations should be discussed with clients.

Clinical, histopathologic, cystoscopic, and fluorescence in situ hybridization analysis of proliferative urethritis in 22 dogs

Background

Proliferative urethritis (PU) is a lower urinary tract disease of dogs characterized by frond‐like lesions in the urethra. The etiology of PU is unknown, although an association with bacterial cystitis is reported.

Objectives

Deep‐seated bacterial cystitis is associated with PU, particularly in dogs with neutrophilic or granulomatous inflammation.

Animals

Twenty‐two client‐owned dogs with PU and 5 control dogs euthanized for non‐urinary disease.

Methods

In retrospective analysis, medical records of dogs with PU from 1986 to 2016 were reviewed. Signalment, clinical signs, cystoscopic findings, antimicrobial use, and results of urine, bladder, or urethral tissue cultures, if available, were recorded. Histopathology was reviewed and classified as lymphocytic‐plasmacytic (LP), neutrophilic, LP‐neutrophilic (LPN), granulomatous, or pleocellular. Eubacterial fluorescence in situ hybridization (FISH) was performed on 18 tissue samples (13 cases, 5 controls), with subsequent evaluation of bacterial species.

Results

Of the 22 dogs, 9 had LP urethritis, 6 had LPN, 4 had pleocellular, and 3 had neutrophilic urethritis. Of note, 7 of 13 PU samples were FISH+ for adherent or invasive bacteria; 1 of 5 controls were FISH+ for adherent bacteria. Five dogs had negative urine and tissue cultures when FISH was positive. There was no association detected between the type of urethral inflammation and the results of urine and tissue culture or FISH.

Conclusions and Clinical Importance

The type of inflammation varied widely in these 22 PU cases. Deep‐seated bacterial urethritis could be contributing to the inflammatory process in some dogs, regardless of the inflammation type. Urine and tissue cultures likely underestimate bacterial colonization of the urethra in dogs.

Palliative ultrasound-guided endoscopic diode laser ablation of transitional cell carcinomas of the lower urinary tract in dogs

OBJECTIVE

To describe the development of ultrasound-guided endoscopic diode laser ablation for palliative management of urinary tract obstruction due to transitional cell carcinoma (TCC).

DESIGN

Prospective case series. Animals-38 dogs with urinary tract obstruction or potential obstruction caused by TCC.

PROCEDURES

Diagnosis of TCC of the urinary bladder and urethra was made by means of transabdominal ultrasonography and transurethral endoscopic biopsy. Transurethral endoscopic near-infrared diode laser ablation was performed to debulk and remove obstructive and potentially obstructive TCC lesions. Transabdominal ultrasonography permitted proper alignment of the endoscope and laser fiber for monitoring laser fiber penetration and subsequent tissue alteration or ablation. The primary outcome measured was median survival time.

RESULTS

Median survival time for all dogs was 380 days, with a range of 11 to 1,906 days. There was no significant difference in survival time between dogs that had TCCs with urethral involvement versus dogs that had TCCs without urethral involvement. Complications were stranguria, hematuria, stenosis at the cystourethral junction, spread of TCC within the lower urinary tract, spread to the urethrostomy site, urethral perforation, and bacterial cystitis.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggested that ultrasound-guided endoscopic diode laser ablation holds promise as a palliative treatment for dogs with TCC of the urinary tract. Ultrasonographic guidance and monitoring during laser irradiation was a useful addition to endoscopically applied transurethral diode laser ablation.

Subtotal vaginectomy for management of extensive vaginal disease in 11 dogs

OBJECTIVE

To report (1) a surgical technique for subtotal vaginectomy using a combined abdominal and vestibular approach; (2) intra- and postoperative complications; and (3) long-term outcome.

STUDY DESIGN

Retrospective case series.

ANIMALS

Female dogs (n = 11) with extensive intramural vaginal disease.

METHODS

Through a ventral median celiotomy, the cranial aspect of the vagina was freed and ovariohysterectomy (OVH) was performed in intact females. After episiotomy, the vaginal wall was incised at the vestibulovaginal junction cranial to the urethral orifice, and the vagina freed from any remaining pelvic attachments. Dogs were reexamined at 4 weeks and 6 months. Long-term outcome was evaluated by contacting the primary veterinarian by phone.

RESULTS

Five dogs had benign vaginal disease and 6 had malignant vaginal neoplasia. A combined abdominal and vestibular approach permitted subtotal vaginectomy in all dogs; 6 dogs also had OVH. No major complications occurred and clinical signs had resolved by 4 weeks. One dog with malignant neoplasia was euthanatized 3 months later for metastatic disease and 1 dog developed postoperative urinary incontinence. Local recurrence or metastases were not identified in the other dogs.

CONCLUSION

Combined abdominal and vestibular approach for subtotal vaginectomy allowed complete resection of extensive vaginal lesions, was not associated with major complications, and outcome was favorable.

Fibrossarcoma uretral primário em cadela

Relatou-se um caso de fibrossarcoma localizado na uretra média de uma cadela, sem raça definida, que apresentava sinais de polaquiúria, estrangúria e hematúria no início da micção. O animal também apresentava poliúria, polidipsia, êmese e anorexia há dois dias. Os exames complementares levaram ao diagnóstico de hidronefrose bilateral, hipoplasia renal direita e massa em uretra causando dilatação dorsal de sua porção média. A biópsia não foi realizada antemortem devido ao estado geral do paciente, que, mesmo com a instituição de tratamento para doença renal crônica, não apresentou progresso. A uretrocistografia retrógrada e a histologia foram os exames decisivos para detectar o fibrossarcoma uretral. A ultrassonografia e a citologia por sondagem traumática não foram conclusivos, devido ao fato de a massa apresentar-se em região media de uretra e o caráter pouco esfoliativo da neoplasia.

Delayed Urethral Obstruction After Uterine Torsion in a Pregnant Dog

A 4 yr old pregnant female shih tzu was presented with abdominal discomfort and bloody vulvar discharge. The nongravid uterine horn was reflected caudally over the trigone, obstructing urine outflow. A cesarian section and ovariohysterectomy were performed. Postoperatively, the hematuria and pollakiuria resolved. Seventeen days later, the pelvic urethra was completely obstructed by a soft tissue mass that was identified by rectal palpation, blocked catheterization attempts, contrast radiography, ultrasonography, and surgery. Management included temporary cystostomy tube and definitive prepubic urethrostomy. Histologic diagnosis was severe, multifocal, necrosuppurative urethritis with fibroplasia, fibrosis, and cellulitis, apparently secondary to ischemia. Delayed urethral obstruction is a potential complication of canine uterine torsion.

Vaginourethroplasty as a salvage procedure for management of traumatic urethral rupture in a cat

This report describes a cat that suffered pelvic urethral rupture associated with multiple pelvic fractures. A vaginourethroplasty was performed as a salvage procedure, via intrapelvic anastomosis of the proximal urethra to the caudal vagina, following failure of a primary urethral anastomosis. Urinary diversion was achieved via tube cystostomy and a vagino-urethral catheter was maintained for 3 days postoperatively. Anterograde cystourethrography was performed at 7 days and 14 days postoperatively. Absence of contrast leakage from the vagino-urethral anastomosis was documented at 14 days postoperatively and the tube cystostomy was removed. An Escherichia coli urinary tract infection was treated following removal of the tube cystostomy and subsequent urine culture revealed no evidence of urinary tract infection. The cat retained normal urinary continence and elimination behaviour during the 7-month follow-up period. Vaginourethroplasty could be considered as a salvage option for management of traumatic pelvic urethral rupture in the neutered female cat.

Evaluation of carbon dioxide laser ablation combined with mitoxantrone and piroxicam treatment in dogs with transitional cell carcinoma

CASE DESCRIPTION

8 dogs that underwent carbon dioxide (CO2) laser ablation of transitional cell carcinoma in the bladder trigone and proximal portion of the urethra and were also treated with mitotranxone and piroxicam.

CLINICAL FINDINGS

Transitional cell carcinoma of the bladder frequently involves the trigone and urethra and can be difficult to manage surgically. Dogs underwent laser ablation of the primary tumor and were treated with mitoxantrone at a dosage of 5 mg/m2)every 3 weeks for 4 treatments. Piroxicam was given at a dosage of 0.3 mg/kg (0.14 mg/lb) once daily for the remaining life of the dog.

TREATMENT AND OUTCOME

Median and mean disease-free intervals were 200 and 280 days, respectively. Median and mean survival times were 299 and 411 days, respectively. Adverse treatment effects were observed in 2 dogs; signs included mild, self-limiting inappetance and lethargy. The procedure appeared to be well tolerated; all treated dogs had rapid resolution of clinical signs of disease of the lower portion of the urinary tract.

CLINICAL RELEVANCE

Although survival times achieved with CO2 laser ablation and treatment with mitoxantrone and piroxicam were similar to survival times associated with chemotherapy alone, resolution of clinical signs was better with the combined treatment.

Urethral transitional cell carcinoma in a cat

A 15-year-old, male neutered cat was referred for investigation of dysuria. A retrograde urethrography was performed which showed two space-occupying masses within the lumen of the mid-to-proximal urethra. Exploratory coeliotomy revealed two urethral masses. Segmental urethrectomy was performed to resect the mass, and the lower urinary tract was reconstructed by vesico-urethral anastomosis. Histopathology showed the mass to be a transitional cell carcinoma with incomplete surgical margins. Tumour regrowth was suspected when dysuria was found approximately 318 days after surgery. Clinical signs were palliated by radiation using weekly fractions of 6 Gy for three weeks. The cat died of unknown causes 386 days postoperatively.

Urethral haemangiosarcoma in a boxer

A seven-year-old, entire female boxer presented with a history of restless behaviour and inappetence. Physical examination revealed that the dog was listless and had a hunched gait. Neurological examination was normal. Abdominal ultrasonography revealed a 4 cm x 4 cm mass in the cranial pelvic canal. Neurological abnormalities were detected three days after presentation, and progressed from proprioceptive deficits to loss of deep pain sensation in the pelvic limbs over a two-day period. The dog was euthanased and postmortem examination revealed that the pelvic mass was a urethral haemangiosarcoma with metastasis to the second lumbar vertebra. This case is unusual as urethral tumours are usually transitional cell carcinomas and frequently present with signs of dysuria.

Vaginectomy and urethroplasty as a treatment for non-pedunculated vaginal tumours in four bitches

Vaginal tumours are uncommon in dogs. Previous reports have shown that 73 to 94 per cent of documented vaginal tumours are benign and pedunculated, often on narrow stalks. Some vaginal tumours are non-pedunculated. They grow in a concentric way either towards the vestibular area or towards the cervix. Their growth can locally affect the function of other organs. Urethral and rectal compression as well as local neurological disturbances have been described. This case series describes total and partial vaginectomy associated with urethroplasty as a treatment for non-pedunculated vaginal tumours in four dogs. These surgical procedures allowed complete resection of the tumour and were associated with low morbidity. Postoperative management and short term outcome are discussed. The final outcome was favourable; throughout the follow-up period, no local recurrence or metastasis was encountered in the animals.

The use of a low-profile cystostomy tube to relieve urethral obstruction in a dog

A 10-year-old, spayed female Dalmatian was diagnosed with granulomatous urethritis causing urethral obstruction. Due to the extensive involvement of the urethra, a urethrostomy was not possible. A commercially available, silicone, low-profile gastrostomy tube was placed as a prepubic cystostomy tube to achieve urinary diversion. This tube is easy to use, has a one-way valve, and lies flush with the skin margin, thereby decreasing the likelihood of inadvertent removal. This tube should be considered to achieve long-term urinary diversion when urethral involvement is extensive.

Evaluation of a bladder tumor antigen test for the diagnosis of lower urinary tract malignancies in dogs

OBJECTIVE

To evaluate the use of a human bladder tumor antigen test for diagnosis of lower urinary tract malignancies in dogs.

SAMPLE POPULATION

Urine samples from dogs without urinary tract abnormalities (n = 18) and from dogs with lower urinary tract neoplasia (20) or nonmalignant urinary tract disease (16).

PROCEDURE

Test results were compared among groups and among 3 observers. The effects of urine pH and specific gravity, degree of hematuria, and storage temperature and time of urine samples on test results were also assessed.

RESULTS

Test sensitivity and specificity were 90 and 94.4%, respectively, for differentiating dogs with lower urinary tract neoplasia from dogs without abnormalities. However, specificity decreased to 35% for differentiating dogs with neoplasia from dogs with nonmalignant urinary tract disease. In dogs with neoplasia, results were significantly affected by degree of hematuria. However, addition of blood to urine from dogs without hematuria had no significant effect on test results. Although intraobserver variation was significant, urine pH, specific gravity, or storage time or temperature had no significant effect on results.

CONCLUSIONS AND CLINICAL RELEVANCE

Although this bladder tumor antigen test was sensitive for differentiating dogs with malignancies of the lower urinary tract from dogs without urinary tract disease, it was not specific for differentiating dogs with neoplasia from dogs with other lower urinary tract abnormalities. It cannot, therefore, be recommended as a definitive diagnostic aid for the detection of lower urinary tract malignancies in dogs.