Drug‐Induced Lupus, Systemic Rheumatic Diseases
Anti-Histone (IgG)
HIST
Line Immunoassay (LIA)
Semi-Quantitative • Negative <1.0 Units • Weak Positive: 1.0-1.5 Units • Moderate Positive: 1.6-2.5 Units • Strong Positive >2.5 Unit
TBD
Mitogen’s anti‐Histone assay is an autoimmune diagnostic test that detects autoantibodies to various histone isoforms. Histones are the primary proteins of eukaryotic chromatin where they are involved in regulating gene expression and also responsible for compacting DNA into nucleosomes.
Antibodies to Histones (H1, H2A, H2B, H3 and H4) are seen in patients with drug-induced lupus (DIL) most commonly associated with procainamide, hydralazine and other drug therapies, idiopathic systemic lupus erythematous (SLE) and juvenile idiopathic arthritis. Note: The sensitivity and specificity of anti-histone antibodies for DIL related to treatment with biological therapies is less than 30%. Follow-up testing for anti-chromatin antibodies is recommended.
Reference: M. Satoh, M. J. Fritzler, and E. K. L. Chan. Antihistone and Antispliceosome Antibodies. In: Lupus Erythematosus: Basic, Applioed and Clinical Aspects, edited by G. C. Tsokos, New York:Academic Press, 2020, p. 237-247.