Idiopathic ischemic priapism in a Shih Tzu

A 14-year-old castrated Shih Tzu weighing 5.4 kg presented with painful penile erection and dysuria that had been ongoing for 2 days. Treatment with salbutamol and gabapentin was initiated, but after 24 hours, the dog had not responded, so it was decided to proceed with penile amputation. The patient went into cardiac arrest during the surgery and died, despite attempted cardiopulmonary resuscitation. During the surgery, the penis was found to have an enlarged, tortuous, purple blood vessel located dorso-caudally to the bulbus glandis. A hemi-circular fibrous mass was found inside the vessel on histopathological examination; this mass may have induced the ischemic priapism by occluding the vein. This report describes a rare case of ischemic priapism in dogs.