A 2 year old female spayed Labrador retriever presented 2 months ago to the WSU Veterinary School with hind limb paralysis of 2 weeks duration. The dog had a 20 month history of inflammatory bowel disease (diagnosed by histologic evaluation of mucosal biopsies obtained by endoscopy) that was controlled with oral prednisone.
On physical examination the dog had increased reflexes in the rear limbs, no deep pain in one rear limb, and no area of pain over the spine. The spleen was enlarged. No ascites was present.
Bloodwork: increased liver enzymes and bile acids. Abdominal ultrasound: splenic thromoses and no portal blood flow seen. No ascites evident. Coag profile normal (previously AT3 had been elevated). MR of the spinal cord: areas of thrombosis. MR of the abdomen: Portal and splenic vein thromboses, splenic thromboses, no portal branches seen in the liver, multiple extrahepatic portosystemic shunts. Titers for Ehrlichia, Lyme's disease, Toxoplasmosis negative.
The dog's neurologic status is gradually improving, with motor returning to the rear limb with deep pain, although it has not returned to the limb that lacks deep pain. An amputation is being scheduled.
The dog's liver enzymes continued to increase and no change was seen in portal flow. On exploratory laparotomy (2 months after presentation), the spleen is revascularized, although the splenic vein itself is thrombosed. The liver looks great (biopsies pending) although multiple shunts are present. The portal vein is thrombosed from its junction with the splenic vein al the way in to the liver. Portal pressure is 19 cm water (normal 8-12 for a dog). The clot in the splenic vein was extremely friable and could not be removed in toto through a venotomy.
Probable differential for this dog is vasculitis (reported as a cause of inflammatory bowel disease in dogs) potentially exacerbated by chronic steroid use (steroids are suspected cause of most portal vein thrombosis in dogs).
The question: Has anyone had experience with medically treating a portal vein thrombosis of more than 2 month's duration, i.e. with streptokinase? What is the usual outcome?