Background: A few weeks back I wrote re: my dog cody who nearly died but made it through some freeky illness. When I brough him home he had a scab on his chest, if you recall I called the vet at the emergency clinic and she denied all involvement in him coming home with a large scab on his chest. My husband wrote a letter to the owner and manager of the vet clinic complaining of the fact we were never told he had this scab (which later turned into an infection and abcess and is now being treated by our regular vet) when we picked him up and we found it ourselves.

I just received a response to the letter. THey appologized for the doctor not telling me about the wound. They do not think it happened with clippers (not a clipper burn) but that due to Cody's hemmoraging his vascular system was compromised and they feel the sore is from vasculitus. I did some research and have not found anything that gives the cause of hemmoraging. They do believe vasculitus is caused from a weak immune system, and they did mention rabies shots.
My question: Has anyone had experience with this disease in dogs? Do you have a good link I could go to and learn more about it? I want to help my Cody any way I can.
THank you
Sharon

The very,very sick often have "leaky" blood vessels which can lead to pooling of fluid in dependent areas. I think this is what they mean by vasculitus in this context. It is a symptom of serious disease, not a disease itself. This fluid leaking out of vessels can be the stage right before death, where the blood pressure falls and the whole system collapses.
Once the fluid leaks out, it can be seeded by whatever bacterial agent is circulating in the blood at the time. Hence the abcess.
It sounds to me like your dog really almost died, it sounds like it was a very close call.