Autoimmune Hemolytic Anemia

Overview


Plain-Language Overview

Autoimmune Hemolytic Anemia is a condition where the body's immune system mistakenly attacks its own red blood cells. This affects the blood, which is part of the circulatory system, leading to a decrease in healthy red blood cells. Red blood cells are important because they carry oxygen to all parts of the body. When these cells are destroyed faster than they can be made, it causes symptoms like fatigue, paleness, and shortness of breath. The immune system produces special proteins called autoantibodies that target red blood cells for destruction. This process can cause the body to break down red blood cells in the spleen or bloodstream. The condition can vary in severity and may require medical evaluation to understand its cause and effects.

Clinical Definition

Autoimmune Hemolytic Anemia (AIHA) is a disorder characterized by premature destruction of red blood cells due to the presence of autoantibodies directed against erythrocyte surface antigens. The core pathology involves immune-mediated hemolysis, which can be classified as warm antibody AIHA (IgG-mediated, active at body temperature) or cold antibody AIHA (IgM-mediated, active at lower temperatures). This leads to anemia with compensatory reticulocytosis and increased erythrocyte destruction primarily in the spleen or intravascularly. AIHA can be idiopathic or secondary to conditions such as lymphoproliferative disorders, autoimmune diseases, infections, or certain drugs. The clinical significance lies in its potential to cause severe anemia, jaundice, and splenomegaly, requiring prompt diagnosis and management to prevent complications.

Clinical Presentation


Diagnostic Workup


Pathophysiology


Treatments


Prevention


Outcome & Complications


Differential Diagnoses


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