More than 95% of patients with an active Lupus Nephritis have anti-C1q antibodies, whereas only up to 50% of patients with SLE do have such antibodies. Patients without anti-C1q antibodies are at lower risk of developing a Lupus Nephritis (negative predictive value). Typically an increase in the titer of anti-C1q autoantibodies can be observed between a few weeks and 6 months before a flare of lupus nephritis occurs. Patients without anti-C1q autoantibodies have a very low risk of developing active lupus nephritis within the following 6 months. In contrast, high titers of anti-C1q autoantibodies are not necessarily predictive of a renal flare. However, patients with high or increasing titers of anti-C1q autoantibodies are at 50% risk to develop an active lupus nephritis, particularly if they have suffered from lupus nephritis in the past. A successful treatment of active lupus nephritis typically decreases the titer of anti-C1q autoantibodies. The titers of anti-C1q autoantibodies can drop below the lower limit of detection and remain undetectable even after reduction or termination of immunosuppression.


Anti-C1q Product Information

Method ELISA
Time to Result 2.5h (approx.)
Sample Type 20 µl serum or plasma  (1:50)
Standard Range 5-400 Units/ml
Sensitivity 1 unit/ml
Order Code EK-AC1QA



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