Autoimmune hemolytic anemia (AIMA, IMHA) is not especially easy to diagnose. Veterinarians must conduct a number of tests to rule out other causes of anemia to ultimately arrive at a diagnosis of IMHA. Owners must be patient and committed to the diagnostic regimen.
The initial database for dogs that show signs suggestive of anemia includes a complete blood count (CBC), a serum biochemistry panel and a urinalysis. The CBC should include what is called red blood cell morphology and a reticulocyte count, because the hallmarks of IMHA include some identifiable and recognizable physical changes to the red blood cell structure, which these tests can disclose. A fresh blood smear is helpful to identify any contributing RBC parasites, such as Babesia and Mycoplasma hemofelis. A Coombs’ test, also called a direct antibody test, and/or a flow cytometry test, as well as a coagulation panel, may also be useful, depending upon the type of anemia involved. Chest radiographs (x-rays) can help identify or exclude metastatic disease as the cause of the anemia, and abdominal ultrasound can be useful to look for evidence of neoplasia (cancer).
Many dogs diagnosed with autoimmune hemolytic anemia will get better with treatment and then relapse a year or so down the road. Owners should be watchful for recurring signs of anemia.