VetNet®
VetNet® AIHA discussion forum
VetNet® Forum
Lifelong Learning Network
www.vetnetlln.ac.uk
Veterinary Recruitment
Premier Partner Program
Canine Autoimmune Hemolytic Anemia (AIHA & IMHA) - following the retic count
| Not that I should even think to ask this today- Trooper the Border Collie is back in the hospital with an infection... But...reading other recent threads...how many of you are maintained on prednisone...with monitoring the retic count. Troop has had a normal PCV since the end of December, but because of an elevated retic count- they have been reluctant to lower the prednisone... She has been about 1.9% (and normal is 1.0%) now that we have had an infection...I wonder if the retic count can be managed by the Imuran ... ANY thoughts??? |
| Chris Connecticut |
| Hi Chris, First so sorry to hear that Trooper is back in the hospital with an infection. Hopefully they will get that resolved soon. On to the retic count, I always think that I am the only one or our Internist that is ever concerned about the retic count. Not many on here seem to mention the retic count. Holly, dachshund, was diagnosed March 2007, and is doing well but still on 4mg of prednisone a day and Imuran daily. Beginning of the year all her numbers were good, including the retic count, so we were down to 2.5mg prednisone every other day, but of course within 2 weeks her retic count went up to 1.4, so the internist said to go back to 5mg a day that we needed to get this retic count down. I often ask the same question about the Imuran. Our internist has always told me that Imuran is more of a therapeudic drug then cyclosporin, which Holly was on last year for several months. Everytime I ask she never really gives me an answer, but always says the prednisone has to be decreased or stopped first before stopping the Imuran. I guess because in Holly's case the disease was slow for her taking place over about 5 months before her PCV went down to 8. One thing the internist says is that if the retic count is still above normal, then destruction is still going on and will eventually lower her PCV again. Is and has Trooper been on Imuran from the start? Hope this helps. Linda |
| Linda Sapphire |
| Hi Chris, Reticulocytes are a confusing part of the blood work. I spent a month studying it before I really was able to understand it fully. But here is what I have come away with from that. All body systems are interconnected in a complex dance. In essence, the body would like everything to stay in a state of homeostasis. If one thing goes too low, another thing monitoring that system acts in some way to get things back to normal. When our dogs become ill, those systems can sometimes get out of whack. One thing goes down but for some reason the other system has a hard time getting the whole ball rolling. In a normal dog (or human), if the combination (or relationship) of the pcv, the count of the red blood cells and the hemoglobin content of the red blood cells are all within a normal range, reticulocytes (baby blood cells) are created from precursor cells in the bone marrow, mature into red blood cells and are sent out into circulation to replace old worn out rbc. The body will be very happy with the oxygen carrying capacity of the rbc in circulation. RBC live about 120 days and when worn out, are dissembled in the spleen and the parts are either reused or removed from the body. Some reticulocytes will generally be out in circulation in a healthy animal, generally around .5% to 1% of the total count of red blood cells or an absolute number around 60,000. When the number of red blood cells drops below a certain point and the hemoglobin carrying capacity for oxygen drops below a certain point (and thus pcv falls below normal), the body begins to realize it doesn't have enough oxygen for the body cells. It calls to the bone marrow to make more baby blood cells, reticulocytes, and send them out early into the general circulation. They aren't very good at carrying O2 for a few days so they are kind of like dead weight. They show up on the blood smear as larger and containing RNA. After about 3-5 days they drop the RNA and mature into RBC. In hemolytic anemia, the RBC are being destroyed quicker than the body can make new ones. So there is a rush of reticulocytes going into the blood stream trying to mature. With severe anemia, say 11% PCV, there could be as many as 5% or more with an absolute number as high as 500,000! This is called reticulosis. I like to use the "filling the glass with water" analogy. Say you fill a glass with water from the tap and finish filling it. You stop the tap and the glass stays full, perhaps occasionally needing a touch up because of evaporation. But what if the glass has a hole in the bottom? You would keep running the tap to try to fill the glass but eventually you are not going to be able to keep up, the glass will begin to empty. This is reticulosis. In autoimmune hemoytic anemia it signals red blood cell destruction. What is hard for us to understand is after the crisis is over, the pcv seems to be normal, but we keep seeing this reticulocyte count bounce around a little. Will it finally settle out? Well, what would happen if during the severe crisis, our dog was very sick and is still recovering from things like liver problems or maybe a kidney infection? Do things like that affect the blood making process? How about diet and nutrition? Is the thyroid normal? Did the adrenal glands recover fully? Are all these new blood cells really healthy ones that operate at peak efficiency? A reticulocyte count of 1.9% must be viewed in a relationship to the number of red blood cells and the current PCV. If I told you that my dog's pcv just hovers around 37-38% but his reticulocyte count is .9% you might think something is wrong. But in reality his body is quite happy with the quality and number of red blood cells and the amount of hemoglobin they contain. Perhaps your dog's body needs a higher PCV than he is at. Some breeds have a normal requirement for PCV's higher than 55%! For example, Greyhounds normally have a PCV of greater than 60%. Other breeds can get by fine with apparently very low PCV, puppies tend to have lower pcvs. If I were to test my dog's blood every week and I saw the PCV fluctuate from 45% to 32% to 30% and there was an accompanying reticulocyte count from 1.9% to 3% to 5%, I would be very worried. There is a call for a lot of reticulocytes and a decrease in the PCV. Something is destroying RBC. If I tested Chance every week and I saw 39% one week and 37% next week and then 38% and the retic count was .9% to 1.4% and then 1%, I would not be worried. His overall health is excellent and clinically the vet would say, "I am not worried, he looks great!" An infection could impact the whole process and indicates that clinically, Trooper might not be as well as he could be yet. This comes under the category: Stress to the body. If Trooper has been at the same dose of prednisone for a very long time, it might be time to ask the vet if they think another drug might be able to take over some of the job of the prednisone. High doses of prednsone for long periods are not necessarily a good thing and is one of the reasons that other drugs are brought in. I can't tell you what you should do, but I hope that I have given you some information to help you think about this process and understand it better. Patrice |
| Patrice NY |
| Thanks for your reply..Troop is home this morning, with a full leg bandage and that big hood...she does not appreciate it..and 2 antibiotics. Anyway...the vet at the center (not the internist) encouraged us to start to lower the prednisone...so...after 2 or 3 weeks - and healing I hope, and another round of blood work...we may go on the plan. Antibiotics look like at least 10 days. Any suggestions on wound healing for our pups?/ |
| Chris Connecticut |
| Thanks for your responses....I will be getting a retic count next week....and lets see what happens??? |
| Chris Connecticut |
This thread was discussed between 30/03/2008 and 09/04/2008
Canine Autoimmune Hemolytic Anemia (AIHA & IMHA) forum index
This thread is from the Vetnet archive. The live Vetnet forum is active now.
