Allandale Veterinary Clinic

Featured Pet: Wednesday

Our featured pet, Wednesday, is a 22 month old female American Pitt Bull mix.

Wednesday came in one day in January not eating or drinking and feeling lethargic. An unusual behavior for this year and half old rambunctious Pit Bull mix. She was urinating brownish red urine and had been vomiting for a day. She had lost 3 lbs recently and her gums were very pale and even had a yellow color to them. We were able to perform lab tests here in the clinic and get a diagnosis that same day that would allow us to initiate rapid and life saving treatment. Wednesday had a severe form of anemia called Immune Mediated Hemolytic Anemia (IMHA).

Immune-mediated hemolytic anemia is a condition where the patient’s immune system begins attacking his or her own red blood cells. In this condition the red blood cells become quickly coated with tiny antigens, essentially marking these red blood cells for destruction. When the red blood cells are destroyed the patient becomes anemic, and will feel cold and weak. Because the red blood cells are being destroyed internally (and not lost through bleeding), the patient will become yellow-tinged (jaundiced) rather than pale. Once they have lost most of their red blood cells the patient will no longer be able to oxygenate their body and death is imminent. Quick detection and treatment usually provides a 75% or better chance of surviving. Similar disorders involve the platelets only (thrombocytopenia), which causes bleeding problems or a combination of both (Evans syndrome, see archived article on Harley) a very difficult disorder to get a handle on.

Anemia is often measured in terms of percentage or pack cell volume (PCV), which is the percent of the blood that is red blood cells. Normal for a dog is about 45-55% and Wednesday’s PCV on day one was 24%. She was started on high dose steroid treatment, which suppresses the immune response against her own cells. Unfortunately this treatment usually takes 3-5 days to make a difference and the next day her PCV was 17% and she was feeling worse. We needed to buy her time with a blood transfusion so our drugs had a chance to do their job. She was given 2 units of universal donor blood which brought her count back up to 24% and she was started on Cyclosporine a drug used in transplant patients to prevent rejection. The next 3-4 days were touch and go and she required close monitoring. She almost needed more blood but on the 5th day her PCV started climbing. It climbed all the way to normal over the next month.

Wednesday continues to do well but is still on medication. She must be monitored regularly as we slowly wean her off the immunosuppressive drugs. It is also possible she may have a relapse but most dogs with this problem go on to live normal healthy lives. We do not know what caused Wednesday’s IMHA which is frequently the case with this syndrome. Depending on which of several studies are examined, 60-75% of IMHA cases do not have apparent causes. In some cases, though, there is an underlying problem: something that triggered the reaction. A drug can induce a reaction that stimulates the immune system and ultimately mimics some sort of red blood cell membrane protein. Not only will the immune system seek the drug but also it will seek proteins that closely resemble the drug and innocent red blood cells will be consequently destroyed. Drugs are not the only such stimuli; cancers can stimulate the same reaction Red blood cell parasites often transmitted by ticks create a similar situation except the immune system is aiming to destroy the infected red blood cells. The problem is that it gets over-stimulated and begins attacking the normal cells as well.

There is some thinking that vaccination can trigger IMHA. Insect bites have also been implicated. Both have been associated with the development of AIHA. The relationship between recent vaccination and IMHA development is one of the factors that has led most veterinary schools to go to an every 3-year schedule for the standard DHLPP vaccine for dogs rather than the traditional annual schedule. We here at Allandale Veterinary Clinic practice the same philosophy and avoid excessive vaccination.

Wednesday’s story has a happy ending thus far, she is robust and active again and the owners are pleased she is doing well. If you note similar symptoms in your pet, tired anorexic and pale gums, don’t delay, get them in for an exam right away.

Previous Featured Pet: Harley

Previous Featured Pet: Cooper