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Canine Autoimmune Hemolytic Anemia (AIHA & IMHA) - Dexter, removal of spleen
| His levels are dropping daily and he is the maximum dose of Pred, Cyclosporine and Azan that he can have. Can'd find any cause for it apart from the fact that his body does not appear to want to fight. vet is considering removing his spleen, anyone heard or had that done with their little one. Not sure he will survive op if he loses too much blood. At the moment we are being lead by the Vet as the next steps with his treatment, just wish we could keep it at a level. He liver and Spleen are enlarged due to the Preds, which I understand is quite normal side effects. Due at Vets in morning looking at the colour inside his mouth, I fear his PCV has dropped even lower. |
| Bev England |
| Dear Bev, I am so sorry to hear about these developments with Dexter. How long has he been on these meds? If it is only a short time, they may start to be more effective given some time. Many of us have had to give transfusions while we waited for the drugs to kick in. Have you talked with your vet about this? Chance has had his spleen removed, not specifically for this reason your vet wants to, but for another reason at a time 2 months earlier than his diagnosis of anemia. I can explain to you the functions of the spleen and why your vet is considering this operation. Humans and dogs both have spleens. It is actually part of the lymphatic system and participates in immunity. However, it also plays a large role in the circulatory system as well. It's major day to day job is to take old worn out red blood cells and platelets, break them up and macrophages help the body recycle the materials in them. It does this by passing blood cells through very tortuous pathways that weave back and forth tightly in the spleen. The young healthy blood cells can navigate tight corners because they are supple. Older cells can't and they break apart. The average life span of a rbc is about 120 days. So this process occurs all the time as cells age. When the spleen is removed, this job falls to the liver and the bone marrow and they do an amazingly adequate job. Another function of the spleen to to produce B cells which develop into antibody producing plasma cells. A third function is to store blood and release it when there is a great demand for it. My vet says it is like an "instant transfusion." Dogs have incredible capacity for storing blood and use this function to a greater degree than humans do. Imagine you are a sleeping dog in the wild and suddenly your alert ears hear a sound that indicates danger. The spleen has been holding an enormous amount of blood in it during sleep. Suddenly strong muscles of the spleen squeeze it and release all this blood back into circulation so the dog can jump up to fight this enemy. Or, for most of us, it is the ability of a sleeping dog to reach the kitchen in a split second when they hear the cookie door open. Studies done on dogs have indicated that they can actually have anemic levels of blood circulating while they are asleep, something called nocturnal anemia. Most of the blood is in the spleen. This is important because it means that dogs can live ok without a spleen as far as the need for circulating blood goes. They will have a lower average packed cell volume or hematocrit, but they can function ok. Another function of the spleen in dogs is to destroy cells that contain blood parasites. Remember how I said that the pathways that the cells travel is very tortuous? If a cell has a blood parasite inside, it is not healthy and as it passes through the spleen it can break apart spilling the blood parasite. The body's immune system immediately comes and destroys the dangerous invader. It then mounts a systematic attack on these parasites by recognizing the antigen of the disease and developing antibodies to attack. Killer lymphatic t-cells are made that come and attach to the blood cells that have these antigens on them identifying them as "not self." They hook on and destroy the blood cell with the bad thing inside. So if a dog is exposed to a tick disease, the immune system can sometimes mount an attack to this disease and possibly eliminate it in the early stages. A dog without a spleen has less of a chance at doing this properly and so they need special consideration when exposed to tick diseases. What your vet has read in hematology textbooks is that the spleen can sometimes go crazy in this immune system function of destruction. It can begin to see all the red blood cells as "not self." It mounts an attack to red blood cells and destroys them. So the spleen is considered a "site of destruction." You and I know this as autoimmune hemolytic anemia. Or if it is caused by a foreign invader, immune mediated hemolytic anemia. In either case the result is the same, red blood cells are being destroyed. This is called hemolysis. Lysing or destroying heme or red blood cells. Medical literature says that removing the spleen may possibly stop this process or slow it down. I think currently there is not much research to show whether or not this is truly effective. Vets who are experienced in treating AIHA may have clinical experience that it is effective. There may be other vets who do not find in their practice that it is effective. Until there are major studies proving or disproving this, it really falls into the clinical experience realm. The considerations you need to keep in mind with this surgery are the possible drawbacks of a major surgery when Dexter is so ill right now. Can he recover ok from a surgery like this? What are the risks of using anesthesia on such a sick dog? What is the skill level of the vet doing the surgery and do they have instant access to blood transfusions that are properly matched to your dog? What is the vet's actual clinical experience with the efficacy of this surgery? If this were me I would also want to know what other causes of this destruction have actually been explored. In medical terminology they call this "ruling out" all causes. Did they do a full panel tick borne disease test? Have they examined the dog carefully and done at least an x-ray to see if there are any tumors? Did they take a complete history to discover recent travel, exposure to certain drugs or chemicals, possible ingestion of coins containing zinc? Did this dog ever eat any food containing onions? Have they tested the thyroid function? Are the kidney's functioning properly? Have they suggested a bone marrow biopsy to determine the number of and type of cells? The removal of the spleen should probably be suggested after all these things have been ruled out. Chance is doing fine now without a spleen, as most dogs do. His pcv or hematocrit is always lower than most other dogs but that doesn't stop him from taking 3 hour walks. I think he sometimes gets a little more tired and has to lay down for a bit but he will get right back up again. We will always have to pay special attention to protecting him from tick diseases as he has less ability to fight them off himself. I hope that I have given you a complete but understandable look at what is involved in removing the spleen and that this will help you decide what to do. My best to you, Patrice |
| Patrice New York State |
| Patrice Thanks for the lenghty and informative reply. Dexter has had scans, xray's, blood screening's for poisoning and the only thing we know is that he had an infection when he first went down with this disease. We believe that we have found out why his levels have been falling, he has a very upset stomach and runny number two's. Therefore concerned that not receiving full dosage of drugs. Could this be the case !! God I hate all this and then to top it off I thought that this was only a disease that Animals suffered from and today found out that many Humans in UK are also going through this. I think this must be worse than any cancer, my heart goes out to them as well as everyone else on this forum also suffering. God Bless you all. Bev |
| Bev Essex |
This thread was discussed on 09/03/2008
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