Study of Antichromatin Antibodies As A Marker of Lupus Activity and Lupus Nephritis.

Systemic Lupus Erythematosus (SLE) is a chronic and potentially fatal autoimmune disorder characterized by the production of auto-antibodies that cause widespread tissue damage. Validate Antichromatin antibodies as a biomarker of renal involvement in SLE and how their titers correlate with systemic lupus activity measure (SLAM) index among a sample of Egyptian systemic lupus patients. The study was conducted on 60 patients diagnosed according to ACR criteria for diagnoses of SLE (Group I) and 25 age matched healthy controls (Group II). Group I was divided into 30 patients without nephritis group A 1 and 30 patients with nephritis group IB. (anti-dsDNA, Antinuclear antibodies ANA), rheumatoid factor (RF), Complement component C3, C4 and antichromatin antibodies were done for all patients and controls. Serum antichromatin antibodies were positive in all cases of SLE and negative in all control subjects and were higher in group1B than group IA also; there were significant positive correlation between antichromatin antibodies and SLAM score of disease activity and classes of nephropathy. In conclusion, measurement of antichromatin antibodies is a useful addition to the laboratory work up for diagnosis and monitoring of SLE and prediction of lupus nephritis.