Persistent Hymen and Pyocolpos in a Female Shih-Tzu Dog

A 9-year-old intact female Shih-Tzu was presented with abdominal pain and abdominal distension. Since the animal’s birth, the owner had never observed proestrous bleeding in the patient. Ultrasonography revealed segmental enlargement of the genital system. An ovariohysterovaginectomy was performed to remove the genital mass. The vagina was grossly dilated as a result of being filled with a solid black-green substance. A vaginogram was performed. Based on the surgical findings and vaginogram results, an imperforate hymen was diagnosed. One month from the first surgery, a stump pyocolpos developed between the sutured site and the obstructed portion. The persistent hymen was removed by endoscopy. However, peritonitis and sepsis developed after the procedure, and the dog died. Therefore, During operation of persistent hymen, a cruciate incision over the hymen strongly recommended to avoid additional post operative complications.