Causes of immune-mediated hemolytic anemia

Physical examination revealed pale mucous membranes with mucus, a rapid heartbeat, and adequate breathing. Symptoms include splenomegaly, hepatomegaly, jaundice and fever. Animals have characteristic lesions of anemia and skin lesions. The injured areas are the tail, nose tip, etc. Blood coagulation is more common. Next, let’s take a look at the causes of immune-mediated hemolytic anemia so that everyone can understand it.

1. Definition

Immune-mediated hemolytic anemia is a type II hypersensitivity reaction caused by a direct cytotoxic reaction between antibodies on the surface of red blood cells and antigens. Direct destruction by antibodies includes intravascular hemolysis and extravascular phagocytosis.

2. Causes

Primary or autoimmune hemolytic anemia is the result of antibody structure antagonizing endogenous non-alternative surface antigens. Secondary immune-mediated hemolytic anemia is the result of antagonism between antibody structures and alternative surface antigens. The causes are mainly drugs and various infectious factors, which is the most common form of confirmed immune-mediated hemolytic anemia. The disease is hereditary in dogs, and is particularly common in Poodles, Old English Sheepdogs, Irish Setters and Cocker Spaniels, especially in female dogs. Over 50% of cats with immune-mediated anemia are associated with feline leukemia virus. Hematobartonellosis and lymphoma are common in cats, with ancestry and sex having no bearing on the incidence.

3. Pathology

Intravascular hemolysis is enhanced by complement activity, and serum immunoglobulins IgM and IgG are highly agglutinated. Extravascular phagocytosis occurs mainly in the spleen and liver or to a lesser extent in the bone marrow. Generally, red blood cells coated with IgG are transported in the spleen, and red blood cells coated with IgM are transported in the liver.

IV. Clinical symptoms

Physical examination revealed pale and mucous membranes, tachycardia, and rapid respiration. The decrease in blood hematocrit causes a systolic heart murmur, and extravascular phagocytosis causes splenomegaly and/or hepatomegaly, as well as symptoms of jaundice and fever. In addition to the characteristic lesions of anemia, the animals also showed skin lesions, especially on the tail, ear tips, nose tip, nail beds, and necrosis in peripheral circulation areas. This is the most common sign of blood clotting at low temperatures in immune-mediated hemolytic anemia.

5. Differential diagnosis

It should be distinguished from diseases such as systemic lupus erythematosus, blood parasitic diseases, poisoning, infectious diseases (such as leptospirosis), cell mechanism defects in the body, tumors, disseminated intravascular coagulation (DIC) and hypersplenism.