Recessed vulva: An overlooked cause of chronic UTI in dogs
Why you should consider this anatomic anomaly in female dogs with recurrent urinary tract infections-and how you can fix it.
Photo 1A: The perineal region of a dog. Note that the vulva is not visible.
No doubt in your practice you’ve seen many urinary tract infections (UTIs). Dogs with UTIs can present with a history of frequent or inappropriate urination, accidents and a change in the color or odor of urine.
Differential diagnoses for UTIs can include bacterial cystitis, renal or cystic calculi, prostatic disease, cystic diverticula, neoplasia, urinary retention and vaginitis. Some cases have multiple contributing factors.
First-time, uncomplicated cases often are treated empirically with antibiotics. Many cases respond well, achieving resolution of the infection and clinical signs. However, dogs with recurrent infections require a more thorough evaluation.
The recommended diagnostic workup for recurrent UTIs should include complete physical examination, baseline blood work, urinalysis, urine culture and imaging with abdominal radiography, ultrasonography or both. Cystoscopy also can be useful in some patients. These tools provide the information needed to reach a definitive diagnosis, initiate appropriate treatment and resolve the UTI.
Photo 1B: The dog in Photo 1A after being shaved and prepped for surgery. Note the prominent dorsal vulvar skin fold completely covering the vulva.
Don’t overlook a recessed vulva
One commonly overlooked physical examination finding that may play a significant role in recurrent UTIs in female dogs is a recessed, or “hooded” vulva. Female dogs with a large skin fold effectively covering the vulva are highly susceptible to perivulvar dermatitis and recurrent UTIs. These dogs may also present with the complaint of incontinence. While perivulvar dermatitis may not be the only abnormality, it’s often a significant contributing factor and should be addressed.
Photo 1C: A preoperative photo of the dog in Photos 1A and 1B. The excessive skin is being held up to expose the vulva and to determine how much skin to remove.
The utility of an episioplasty
Episioplasty, the treatment of choice for dogs with excessive perivulvar skin folds, is a relatively simple procedure in which skin from between the anus and vulva is resected. The resulting wound is closed, and the previously hidden vulva is thereby exposed. See Photos 1A-1F and 2A-2C to see how two cases of recessed vulva were resolved.
Photo 1D: An intraoperative photo of the dog in Photos 1A-1C after skin resection.
Photo 1E: An intraoperative picture of the dog in Photos 1A-1D just before apposing the wound margins. The surgeon is checking to see if adequate skin has been removed to sufficiently expose the vulva.
Photo 1F: The dog in Photos 1A-1E after surgery.
Photo 2A: The perineal region of a dog with a recessed vulva with large lateral skin folds.
Photo 2B: The dog in Photo 2A immediately after surgery.
Photo 2C: The dog in Photos 2A and 2B two weeks after surgery.
The difficulty in this procedure is knowing how much skin to remove. Inadequate removal can result in continued dermatitis and UTIs and an unsatisfactory result (Photos 3A-3C). However, excessive skin removal can lead to tension on the surgical site and wound dehiscence.
Photo 3A: The perineum of a dog that had previously undergone an episioplasty with inadequate skin resection.
Additionally, there’s debate about when the procedure should be done. Many of these dogs present at younger than 1 year of age. Should you wait until maturity is reached? Will the dog outgrow its episioplasty?
In my opinion, episioplasty is indicated when excessive perivulvar skin fold is identified as a factor in a dog’s signs, regardless of the dog’s age.
Photo 3B: An intraoperative view of the dog in Photo 3A after skin resection, prior to wound closure.
Episioplasty should be effective long-term if adequate skin is removed, if there are no concurrent problems or they have been appropriately addressed and if the dog is maintained at a normal body weight. Resolution of the dermatitis, UTI and urine pooling via episioplasty may also result in improvement in previously noted incontinence.
Photo 3C: The dog in Photos 3A and 3B after surgery.
Dr. Janice Buback is a surgeon with Lakeshore Veterinary Specialists in Port Washington, Glendale and Oak Creek, Wis.