Lupus is a complex autoimmune disease where the body’s immune system mistakenly attacks its own healthy tissues and organs, leading to inflammation and damage in various body systems, including the skin, joints, kidneys, and blood cells. A common question arises regarding its impact on fundamental biological characteristics, specifically whether lupus can alter an individual’s blood type. This article addresses this query, explaining the stable nature of blood types and detailing how lupus affects the blood.
What Determines Your Blood Type?
Blood type is a stable, lifelong characteristic determined by genetics, inherited from both parents. It is classified based on specific protein molecules called antigens on the surface of red blood cells. The main classification systems are ABO and Rh.
In the ABO system, individuals have A, B, both (AB), or neither (O) antigens on their red blood cells. The Rh system determines if blood is positive or negative based on the RhD antigen. For example, someone with A antigens and the RhD antigen has A-positive blood. These antigens are an integral part of the red blood cell structure, meaning a person’s blood type remains constant from birth.
Lupus and Blood Type: A Clear Answer
Lupus does not change a person’s inherent blood type. Blood type is genetically determined and remains fixed throughout life. The misconception that lupus might alter blood type could stem from the disease’s effects on blood components and its ability to cause other hematological issues.
While lupus can lead to significant changes in blood cell counts and function, these effects are distinct from altering the fundamental ABO or Rh classification of red blood cells. For instance, certain lupus-related conditions might cause discrepancies in blood typing tests. These are due to antibodies or other factors interfering with the test, not a change in the individual’s genetic blood type.
How Lupus Impacts Your Blood (Beyond Type)
Even though lupus does not change blood type, it significantly affects blood cells and components, leading to various hematological conditions. These conditions arise from the immune system’s attack on healthy blood cells. The impact can range from mild to severe, affecting different blood cell types.
One common issue is anemia, characterized by a reduced number of healthy red blood cells or low hemoglobin. About half of all people with lupus may experience anemia. This can occur due to chronic inflammation, which interferes with red blood cell production, or autoimmune hemolytic anemia (AIHA), where the immune system directly destroys red blood cells. Anemia can lead to symptoms like fatigue and shortness of breath.
Lupus can also cause leukopenia, a low white blood cell count. This often involves a decrease in neutrophils or lymphocytes, white blood cells crucial for fighting infection. Leukopenia can increase susceptibility to infections, especially when counts are very low. Approximately 95% of individuals with lupus may experience leukopenia.
Thrombocytopenia, a low platelet count, is another frequent blood-related issue in lupus. Platelets are small cell fragments vital for blood clotting. About 20% to 40% of lupus patients may develop thrombocytopenia, which can increase the risk of bruising and bleeding. This condition is often due to the immune system mistakenly attacking and destroying platelets.
Lupus can also increase the risk of blood clots. This is particularly associated with Antiphospholipid Syndrome (APS), an autoimmune disorder that can co-occur with lupus. In APS, the immune system produces antibodies that target certain proteins involved in blood clotting, leading to an increased predisposition for clots in both veins and arteries. Around 30% to 40% of people with lupus have these antibodies, and about one-third of those may develop blood clots. These clots can result in serious complications like stroke or deep vein thrombosis.