Pyometra with inguinal herniation of the left uterine horn and omentum in a Beagle dog

Objective: To describe a unique case of pyometra with inguinal herniation of the left uterine horn and omentum. Case summary: A 7-year-old, 19 kg, intact female Beagle dog presented for surgical treatment of presumptive pyometra and biopsy of a caudal abdominal mass in the left inguinal mammary gland region. Ventral midline celiotomy was performed, and a distended, fluid-filled uterus with passage of the distal aspect of the left uterine horn through the left vaginal process into the inguinal canal was identified. The patient recovered uneventfully following ovariohysterectomy and left inguinal herniorrhaphy. New or unique information provided: This is the first documented report of inguinal herniation of a uterine horn associated with a pyometra.