Hypospadias in animals
Following my son’s urethroplasty when his voiding was dysfunctional, I researched. And I researched some more. I was trying to find some kernel of information I believed I was missing. Something that hadn’t been brought up, I hadn’t asked or hadn’t perhaps *ever* been thought of. After all, we’re moms right? I needed to overturn every stone, ask every expert and understand as best as I could what was going on and how we could fix it. Was it chronic inflammation, was it his kidneys, an infection either of the skin or urinary tract, was it something else beyond a stricture – at that point we were waiting it out with a suprapubic catheter until we were far enough out from the urethroplasty for a re-exam and if needed, a re-repair.
I was researching stranguria, which is the difficulty in micturition where the urine is passed drop by drop, or dribbling, with pain and tenesmus, and came across a case of a a 7 week old male Boston terrier with an incomplete fusion of the urethra distal to the pelvic urethra (perineal hypospadias) and no preputial covering of the glans penis. I hadn’t ever considered hypospadias in animals. This pups’ urethral opening was 8 mm ventral to the anus, and he had an underdeveloped prepuce, ventrally deviated blunt penis, and retained left testicle. His owner had brought him to the vet stating that he dribbled during urination and was unable to form a consistent urine stream. He also presented with mild local dermatitis and penile erythema and inflammation. A urine culture, blood count and serum profile were evaluated.
Due to the risk of chronic recurrent UTIs, scald dermatitis and penile irritation, surgery was scheduled which would include urethral reconstruction with tubularized incised plate (TIP) urethroplasty, bilateral orchiectomy and penile and preputial amputation. His surgical treatment was designed to eliminate the source of inflammation and irritation, help focus the urine stream to reduce urine scald and increase the length of the urethra.
At two weeks post-op the dog’s owner estimated the frequency of urination had improved by 50%, however, similar to pre-op, the stream wasn’t always continuous. A urine culture showed an active mixed Escherichia coli and Enterococcus urocystitis so he was treated with amoxicillin/clavulanate for 14 days. After this round, all signs had improved with the exception of the stream. At one year post-op the dog had a thin stream and the occasional inconsistent stream and the infection had returned. He was re-treated with with amoxicillin/clavulanate for 14 days. At two years post-op he had the same thin, inconsistent stream, however there was still no evidence of stranguria. A voiding cystourethrogram (VCUG) was done to find the cause of the thin and inconsistent stream and recurrent urocystitis. The cystourethrogram showed a small urethral diverticulum, no strictures and an adequate diameter urethra for his smaller breed. This time he was treated with a 4 week course of amoxicillin/clavulanate.
After this last course, the dog had no evidence of pollakiuria or stranguria and was able to form a consistent urine stream. During this visit, the residual urine volume was assessed by catheterizing him just after voiding. To test this, he was allowed to urinate and was sedated, catheterized and syringed. It was concluded there was no residual urine left in his bladder. The dog’s owner was given a final round of antibiotics and instructed to re-test following the course and every month for two months and every two months for a year. If future cultures remained positive, surgery to remove the urethral diverticulum would be considered, otherwise long term antibiotic treatment would be necessary. If he remained asymptomatic, a diverticulum of its size wouldn’t require surgical correction.
The outcome of this case of hypospadias in animals would be the same with humans: in absence of stone formation, incomplete voiding, infection or post void dribbling, hematuria, incontinence, or any other functional abnormality, urethral diverticulae typically wouldn’t be corrected, as the risks of complications from surgery must be considered and outweigh the benefit of removal.