Warm antibody autoimmune hemolytic anemia

Warm antibody autoimmune hemolytic anemia (WAIHA) is a type of autoimmune hemolytic anemia (AIHA) where the body's immune system produces antibodies that target and destroy its own red blood cells (RBCs) at body temperature. This condition is characterized by the presence of IgG antibodies that react optimally at 37°C (98.6°F).

Pathophysiology

In WAIHA, the immune system mistakenly identifies RBCs as foreign and produces autoantibodies against them. These autoantibodies are typically of the IgG class and bind to the RBC surface antigens. The bound antibodies mark the RBCs for destruction, primarily in the spleen and, to a lesser extent, in the liver. This process leads to hemolysis, or the breakdown of RBCs, resulting in anemia.

Symptoms

The symptoms of WAIHA can vary but often include:

• Fatigue
• Pallor
• Jaundice
• Shortness of breath
• Tachycardia
• Dark urine

Diagnosis

Diagnosis of WAIHA typically involves several laboratory tests, including:

• Complete blood count (CBC) showing anemia
• Reticulocyte count indicating increased production of RBCs
• Direct antiglobulin test (DAT), also known as the Coombs test, which detects antibodies attached to RBCs
• Indirect antiglobulin test to detect free antibodies in the serum

Treatment

Treatment of WAIHA may include:

• Corticosteroids such as prednisone to suppress the immune response
• Immunosuppressive drugs like rituximab
• Intravenous immunoglobulin (IVIG)
• Blood transfusions in severe cases
• Splenectomy in refractory cases

Prognosis

The prognosis for individuals with WAIHA varies. Some patients respond well to treatment and achieve remission, while others may experience chronic or recurrent episodes of hemolysis.

Related Pages

• Autoimmune hemolytic anemia
• Hemolytic anemia
• Red blood cell
• Immune system
• Spleen
• Liver
• Corticosteroids
• Rituximab
• Intravenous immunoglobulin
• Splenectomy