Overview
LE cells are abnormal neutrophils that contain phagocytosed, denatured nuclear material and represent a hallmark of autoimmune activity, particularly systemic lupus erythematosus. The LE cell test was historically used to diagnose systemic lupus erythematosus but has largely been replaced by more sensitive and specific immunological tests, such as antinuclear antibody testing. Despite this, identification of LE cells still demonstrates the underlying autoimmune process. A negative LE cell test helps exclude a diagnosis of systemic lupus erythematosus, while the presence of LE cells strongly indicates lupus.
Symptoms
The presence of LE cells does not produce symptoms by itself. Clinical manifestations depend on the underlying autoimmune disease, most commonly systemic lupus erythematosus. Patients may present with fever, fatigue, skin rashes, joint pain, and multisystem involvement. The LE cell test reflects immune-mediated tissue injury rather than causing clinical features directly.
Causes
LE cells form due to an autoimmune reaction in which autoantibodies target nuclear antigens within the body’s own cells. During the testing process, cell nuclei are intentionally damaged, releasing denatured nuclear material known as nucleoprotein. This exposed nuclear material reacts with circulating autoantibodies to form immune complexes. Neutrophils or macrophages then phagocytose this material, resulting in the formation of LE cells characterized by a homogeneous, round nuclear inclusion that displaces the original nucleus to the periphery. This process reflects defective clearance of apoptotic cells, a key mechanism in systemic lupus erythematosus.
Risk Factors
Conditions associated with LE cell formation include systemic lupus erythematosus and other autoimmune disorders such as rheumatoid arthritis, scleroderma, and chronic active hepatitis. Individuals with circulating antinuclear antibodies are at increased risk of LE cell positivity. The likelihood of detecting LE cells is influenced by disease activity, sample handling, and timing of testing, as cellular degradation can reduce detection rates.
Prevention
There are no preventive measures to stop the formation of LE cells, as they result from autoimmune disease processes. Prevention focuses on early diagnosis and management of autoimmune disorders. Proper sample collection and handling are essential for accurate detection. Whole blood should be collected in an EDTA tube, mixed thoroughly, and processed within two hours to avoid cellular degradation. Samples should be transported under refrigerated conditions to preserve cell integrity. While LE cell testing has historical significance, modern diagnostic approaches rely on ANA, anti-dsDNA, and anti-Sm antibody tests for better sensitivity and specificity. LE cell testing remains supportive rather than confirmatory and should always be interpreted alongside clinical findings and advanced immunological investigations.
