Coremans IEM, Spronk PE, Bootsma H, Daha MR, van der Voort EAM, Kater L, Breedveld FC, Kallenberg CG
Changes in antibodies to C1q predict renal relapses in systemic lupus erythematosus

Am J Kidney Dis (Oct) 26:595-601 1995

The authors in this manuscript use the cohort of 151 patients with SLE who were followed in their programs between 1988-1993 at three month intervals and selected the first 17 patients who developed renal relapse, the first 16 patients who developed a relapse in nonrenal organs and 10 randomly selected patients without relapse and measured levels of anti-C1q and anti-dsDNA prospectively. The three groups of patients were well matched with regard to clinical features. Anti-C1q was detected in 12 of 17 patients, primarily with renal relapse compared with 6 of 16 patients with nonrenal flares and 2 of 10 patients who remained clinically inactive. These values were statistically significant. Anti-dsDNA was detected in 13 of 17 patients with primarily renal relapse compared with 15 of 16 patients with nonrenal flares and 5 of 10 patients who were clinically inactive, again statistically significant. Anti-dsDNA and Anti-C1q correlated closely. In patients with renal relapse, both antibodies increased beginning four months prior to relapse and reached a peak at the moment of relapse. In patients with nonrenal relapse, anti-dsDNA remained high for the entire observation period. No changes in these antibodies were seen in inactive patients. The mean time between occurrence of the significant increase in the antibody titer and the moment of relapse was 2.3 months for both antibodies.

With respect to predicting power for these antibodies for the development of relapse, there was no difference in predictive power for renal relapse between anti-C1q and anti-dsDNA. Anti-dsDNA had the highest sensitivity for predicting all kinds of disease exacerbations whereas anti-C1q had the highest specificity for predicting renal relapse. The authors speculate on the potential role the increased levels of anti-C1q found in all patients with a proliferative form of lupus nephritis may play. They suggest that this antibody can be deposited in the glomerular basement membrane as a trapped circulating immune complex and some of their experimental work support this concept. They conclude that serial measurement of plasma C1q and anti-dsDNA are helpful because an increase in the anti-C1q level is associated with renal relapse whereas an increase in the anti-dsDNA is associated with all forms of relapse in patients with SLE. (Krane)

To go back use the BACK button on your browser.
Otherwise click on the desired link to this article below:
Proteinuria/Hematuria : Lupus nephritis