Systemic lupus erythematosus (lupus) is a chronic autoimmune disease where the body’s immune system mistakenly attacks its own healthy tissues and organs. This can lead to widespread inflammation and tissue damage in various parts of the body, including the skin, joints, kidneys, and blood.
White blood cells (WBCs), also known as leukocytes, are a fundamental part of the immune system, defending the body against infections and foreign invaders. Understanding how lupus affects white blood cell counts is important, as these counts often provide clues about disease activity or other health concerns.
Lupus and White Blood Cell Counts: The Typical Scenario
While it might seem intuitive for an autoimmune disease to increase immune cell counts, lupus more commonly leads to lower-than-normal white blood cell counts, a condition called leukopenia. This reduction often involves specific types of white blood cells. Lymphopenia, a decrease in lymphocytes, is particularly common in lupus patients and can be a classification criterion for the disease. Neutropenia, a reduction in neutrophils, can also occur, though it is less frequent than lymphopenia.
The immune system’s misdirected activity in lupus can target and destroy its own white blood cells. Autoantibodies can be directed against white blood cells, leading to their destruction. Inflammation associated with lupus can also suppress bone marrow function, reducing white blood cell production. Additionally, certain lupus medications can contribute to lower white blood cell counts by suppressing bone marrow activity.
Factors That Can Elevate White Blood Cells in Lupus Patients
Despite the common tendency for lupus to cause low white blood cell counts, an elevation might occur in specific circumstances. One primary reason is the presence of an infection. Individuals with lupus are more susceptible to infections due to the disease itself and the immunosuppressive medications often used for treatment. When an infection takes hold, the body responds by producing more white blood cells, particularly neutrophils, to combat invading microorganisms.
Another factor leading to elevated white blood cell counts is severe inflammation during a lupus flare. A flare is a period of increased disease activity where symptoms worsen and inflammation intensifies. The body’s response to this heightened inflammation can cause a reactive increase in white blood cells, especially neutrophils, as the immune system manages widespread inflammatory processes. This rise in WBCs reflects the body’s generalized inflammatory response rather than an external threat.
Certain medications used in lupus treatment can also cause an increase in white blood cell counts. Corticosteroids, such as prednisone, are frequently prescribed to manage lupus symptoms and reduce inflammation. These medications are known to increase neutrophil counts by causing them to detach from blood vessel walls and enter circulation, delaying their removal from the bloodstream, and stimulating their release from the bone marrow. This effect is typically a medication side effect rather than a sign of worsening lupus or infection.
Interpreting Elevated White Blood Cell Counts in Lupus
An elevated white blood cell count in a lupus patient is a signal that requires careful evaluation by a healthcare professional. It is important to distinguish between the potential causes, as the underlying reason dictates the appropriate course of action. For instance, a high white blood cell count might suggest an infection, which would necessitate antibiotic or antiviral treatment. However, if the elevation is due to a lupus flare, the treatment approach would focus on managing the autoimmune activity, potentially by adjusting immunosuppressive therapies.
Doctors consider several factors when interpreting an elevated white blood cell count. They assess a patient’s overall clinical picture, including new or worsening symptoms like fever, chills, or localized pain, which might point towards an infection. Laboratory markers, such as C-reactive protein (CRP) and procalcitonin, can also help differentiate between infection and a lupus flare; CRP levels typically rise significantly with infection but less so during a flare. Additionally, reviewing the patient’s current medications, especially corticosteroid dosages, helps determine if the elevation is a drug-induced effect.
Monitoring and Clinical Considerations
Regular monitoring of white blood cell counts is a standard part of lupus management. This is typically done through a Complete Blood Count (CBC), a routine blood test measuring various blood components, including white blood cells. Frequent CBCs allow healthcare providers to track white blood cell levels over time, detecting significant changes early. This monitoring helps assess disease activity, identify potential infections, and evaluate medication effects.
Regular blood tests help identify active lupus, even with subtle symptoms, and indicate when medication adjustments are needed. Early detection of an elevated white blood cell count can prompt timely investigation, potentially preventing serious complications from an untreated infection or an uncontrolled lupus flare. Consulting a rheumatologist or other healthcare provider is important for interpreting these results and guiding treatment decisions, as they consider the complex interplay of lupus activity, medication effects, and potential infections.