Extraluminal urethral obstruction caused by mesonephric remnant cyst in a female dog

Abstract A 5‐year‐old, female, neutered, Airdale Terrier was referred for investigation of dysuria; 3 weeks previously, ovariohysterectomy had been performed due to pyometra. Abdominal ultrasound revealed a circumscribed fluid‐filled anechoic structure located caudodorsally to the bladder, compressing the pre‐pelvic urethra. An exploratory coeliotomy was performed, and an 8 cm diameter extraluminal cervical cystic structure was identified dorsal to the bladder. The cystic structure was excised along with revision of the uterine stump. The excised tissue was submitted for histopathology, and the fluid contents were submitted for fluid analysis and cytology. Normal urination was observed post‐operatively, and the owner reported no concerns at follow‐up. Urethral obstruction is seen far less frequently in the female dog than in males. Urethral obstruction due to a mesonephric remnant cyst has rarely been described.