Warm autoimmune hemolytic anemia and cold agglutinin (NORD)

Summary

Warm autoimmune hemolytic anemia (WAHA) and cold agglutinin disease (CAD) are autoimmune disorders where the immune system destroys healthy red blood cells. WAHA occurs at body temperature, while CAD is triggered by cold temperatures. Symptoms include fatigue, dizziness, palpitations, and in severe cases, chest pain or confusion. Diagnosis is confirmed through blood tests, including the Coombs test. Treatment includes corticosteroids, rituximab, and in some cases, blood transfusions or spleen removal. While WAHA is more common, CAD typically affects older individuals. Both conditions require careful management to prevent complications such as blood clots or organ damage.

Takeaways

• 😀 WAH (Warm Autoimmune Hemolytic Anemia) and CAD (Cold Agglutinin Disease) are autoimmune conditions where the immune system attacks healthy red blood cells, leading to anemia.
• 😀 WAH occurs at normal body temperatures, while CAD occurs at cold temperatures, typically between 37°F and 39°F (3°C - 4°C).
• 😀 WAH is the most common autoimmune hemolytic anemia and can occur at any age, while CAD generally affects individuals between 40 to 80 years of age.
• 😀 Common symptoms of WAH and CAD include dizziness, palpitations, shortness of breath, dark urine, pale skin, jaundice, and fatigue.
• 😀 Severe cases may cause chest pain, confusion, fainting, abnormalities in heart rate and blood pressure, as well as deep vein thrombosis (DVT) or pulmonary embolism.
• 😀 WAH patients may develop an enlarged spleen, causing abdominal fullness, while CAD patients may experience Raynaud's phenomenon (cold, bluish fingers/toes).
• 😀 Both conditions are caused by autoantibodies: IGG in WAH and IGM in CAD, which target red blood cells for destruction.
• 😀 Primary or idiopathic WAH or CAD has an unknown cause, while secondary cases arise from conditions like infections, autoimmune diseases, or cancers.
• 😀 Diagnosis includes blood tests for anemia (low hemoglobin, low hematocrit, elevated reticulocytes) and specialized tests like the Coombs test for autoantibodies.
• 😀 Treatment includes corticosteroids (e.g., prednisone), rituximab, and immunosuppressive agents. In severe cases, spleen removal and blood transfusions may be necessary.

Q & A

What is the main difference between Warm Autoimmune Hemolytic Anemia (WAHA) and Cold Agglutinin Disease (CAD)?

The primary difference between WAHA and CAD is the temperature at which hemolysis occurs. In WAHA, hemolysis happens at body temperature, while in CAD, hemolysis occurs at colder temperatures, usually between 37 to 39 degrees Fahrenheit or 3 to 4 degrees Celsius.

What symptoms are common in both WAHA and CAD?

Common symptoms of both WAHA and CAD include dizziness, palpitations, shortness of breath, dark urine, pale skin, jaundice, and fatigue. In severe cases, chest pain, confusion, fainting, and abnormal heart rate and blood pressure may occur.

What are the unique symptoms associated with WAHA?

Individuals with WAHA may develop an enlarged spleen, causing a full feeling in the abdomen. They may also experience deep vein thrombosis (DVT), leading to pain, swelling, redness, and warmth in one leg.

What is Raynaud's phenomenon and in which condition is it most commonly seen?

Raynaud's phenomenon is a condition where fingers, toes, ankles, and wrists become cold and painful with bluish or reddish discoloration due to restricted blood flow. It is most commonly seen in CAD.

What type of antibodies are responsible for WAHA and CAD?

In WAHA, IGG antibodies are primarily responsible for tagging red blood cells for destruction. In CAD, IGM antibodies tag red blood cells, causing them to clump together or agglutinate.

How is hemolysis confirmed in individuals with WAHA or CAD?

Hemolysis is confirmed through blood tests showing low levels of haptoglobins, elevated bilirubin, and lactate dehydrogenase. The presence of autoantibodies is detected using a Coombs test.

What are the main treatments for WAHA and CAD?

The main treatments for both WAHA and CAD include corticosteroid therapy, with prednisone being commonly used. In severe cases, rituximab, immunosuppressive agents, or chemotherapy may be considered, along with blood transfusions if necessary.

What secondary conditions can cause WAHA or CAD?

Secondary WAHA or CAD may occur due to infections, autoimmune diseases, or cancers, which can lead to the production of autoantibodies.

How does rituximab help in the treatment of WAHA and CAD?

Rituximab is a monoclonal antibody that targets the immune cells responsible for hemolysis. It can be used in combination with other therapies like prednisone or chemotherapy agents to treat both WAHA and CAD.

What are some preventive measures for individuals with CAD?

Individuals with CAD should avoid exposure to cold, especially on their head, face, arms, and legs, to reduce the risk of hemolysis. This is a critical preventive measure for managing the condition.