Prolonged estrus in an intact Doberman

Abstract

A 17 month old intact female Doberman presented with serosanguinous vulvar discharge of 2 months duration. On physical examination, vulva was moderately swollen with a notable amount of serosanguinous discharge. Vaginal cytology revealed 100% cornification of vaginal epithelial cells, confirming the influence of estrogen and serum progesterone concentrations were < 0.02 ng/ml. On ultrasonography, a 2.0 x 3.0 cm fluid filled structure was identified on the cranial aspect of left ovary. Differential diagnoses included follicular cyst, exogenous estrogen exposure and neoplasia. Based on history, physical examination and diagnostics, a follicular cyst was placed at top of the differential list. Follicular cysts are well recognized in association with prolongation of clinical signs of proestrus or estrus. Most follicular cysts have a granulosa cell lining, are anovulatory, and secrete substantial amounts of estrogen, which explains the clinical signs commonly associated with this condition. These cysts are usually solitary, occur in bitches < 3 years of age, and measure 1 - 1.5 cm in diameter, but some cysts can be as large as 5 cm.1 Most common reason owners seek veterinary care is vaginal bleeding that persists for weeks, rather than the expected 7 - 10 days. Diagnosis of follicular cysts is based on observation of prolonged vulvar discharge, persistent estrous behavior, increased blood estrogen concentrations as evidenced by vaginal cytology findings, and abdominal ultrasonography.2 Ovariohysterectomy was performed. Left ovary and uterine horn appeared enlarged. Histopathology of ovary confirmed a follicular cyst. Surgical recovery and healing were uneventful and the patient’s clinical signs resolved. This case demonstrated a practical approach to the diagnosis and treatment of canine follicular cyst.