A persistent hymen resulting in an open cervix but closed pyometra and pyocolpos in a mixed-breed female domestic dog

Abstract

A rescued mixed-breed (Africanis type), entire, female dog, approximately 2 years old, with an unknown history, presented with a prominent perineal swelling between the anus and vulva. Ultrasound identified it as a fluid-filled structure, and an aspirate revealed an exudate consisting of degenerate neutrophils, bacterial cocci and rods. A vaginal exam showed a persistent hymen, while an abdominal ultrasound revealed distended, fluid-filled uterine loops consistent with a pyometra. Under general anaesthesia, an ovariohysterectomy was performed, and the persistent hymen was resected via an episiotomy to allow drainage of the purulent material. The surgery and recovery were without complications. This report describes an unusual presentation of a pyocolpos and ‘closed’ pyometra because of a persistent hymen.