Vaginal prolapse

From Dog
Vaginal prolapse-hyperplasia in a Great Dane bitch[1]

Vaginal prolapse-hyperplasia syndrome (vaginal edema, vaginal fold prolapse) is a relatively rare obstetrical disorder of dogs characterized by vaginal swelling and protrusion from the vulva[2].

A breed predisposition has been suggested in the Bull Mastiff and Bulldog.

Vaginal prolapse usually occurs during the pro-oestrus and oestrus stages of the sexual cycle. True vaginal prolapse may occur near parturition, as the concentration of serum progesterone declines and the concentration of serum estrogen increases[3].

Vaginal prolapse may be observed in older dogs associated with extreme abdominal contractions associated with dystocia[4][5], constipation or as a consequence of estrogen therapy, fibroepithelial polyps[6] or transmissible venereal tumors.

In rare cases, herniation of the uterine body, urinary bladder, and distal aspect of the colon may occur, resulting in a medical emergency[7].

Diagnosis is usually achieved by digital examination of the vagina and exclusion of other causes, supported with radiographic and ultrasonographic evidence of a primary vaginal disorder. Histopathological examination of vaginal biopsies may help establish a hyperplastic disease.

A differential diagnosis would include vaginal polyposis, vaginal adenocarcinoma, clitoral hypertrophy, urethral neoplasia protruding into the vaginal vault, uterine prolapse, vaginal abscessation or hematoma[8].

In many cases, hyperplastic tissue will regress during diestrus but cystitis is a common sequela due to bacterial overgrowth associated with epithelial damage[9]. Treatments with GnRH or hCG to induce premature ovulation have been used with limited success[10].

Tissue that is excessively traumatized and/or prolapse of the entire vaginal circumference may be removed surgically.

Ovariohysterectomy may be used to prevent recurrence[11].

References

  1. Puppyer
  2. McNamara PS (1997) Chronic vaginocervical prolapse with visceral incarceration in a dog. J Am Anim Hosp Ass 33:533-36
  3. Sarrafzadeh-Rezaei F et al (2008) First report of vaginal prolapse in a bitch treated with estrogen. Anim Reprod Sci 106(1-2):194-199
  4. Prassinos NN et al (2010) Vaginal rupture and evisceration in a dog. Acta Vet Hung 58(3):309-315
  5. Alan M et al (2007) True vaginal prolapse in a bitch. Anim Reprod Sci 100(3-4):411-414
  6. Brown PJ et al (2012) Fibroepithelial polyps of the vagina in bitches: a histological and immunohistochemical study. J Comp Pathol 147(2-3):181-185
  7. McNamara PS et al (1997) Chronic vaginocervical prolapse with visceral incarceration in a dog. J Am Anim Hosp Assoc 33(6):533-536
  8. Manothaiudom K & Johnston SD (1991) Clinical approach to vaginal/vestibular masses in the bitch. Vet Clin North Am Small Anim Pract 21(3):509-521
  9. Kieves NR et al (2011) Vaginal resection and anastomosis for treatment of vestibulovaginal stenosis in 4 dogs with recurrent urinary tract infections. J Am Vet Med Assoc 239(7):972-980
  10. Rushmer RA (1980) Vaginal hyperplasia and uterine prolapse. In: Kirk R.W. ed. Current Veterinary Therapy VII, Small Animal Practice. Philadelphia: WB Saunders Co. pp:1222-1224
  11. Soderberg SF (1986) Vaginal disorders. Vet Clin North Am Small Anim Pract 16(3):543-559