Abstract: SA-PO114

Assessment of the Impact of Serum Levels of Gd-IgA1-Specific IgG Autoantibodies on the Prediction of the Course of Disease in Czech Patients with IgA Nephropathy

Session Information

Category: Glomerular

  • 1005 Clinical Glomerular Disorders

Authors

  • Maixnerova, Dita, General Teaching Hospital, 1st Faculty of Medicine, Charles University, Prague, Czechia
  • Tesar, Vladimir, General Teaching Hospital, 1st Faculty of Medicine, Charles University, Prague, Czechia
  • Hall, Stacy D., University of Alabama at Birmingham , Birmingham, Alabama, United States
  • Reily, Colin, University of Alabama at Birmingham , Birmingham, Alabama, United States
  • Neprasova, Michaela, General Teaching Hospital, 1st Faculty of Medicine, Charles University, Prague, Czechia
  • Skibova, Jelena, Institute of Clinical and Experimental Medicine, Prague, Czechia
  • Suchanek, Miloslav, University of Chemical Technology Prague, Prague, Czechia
  • Honsova, Eva, Institute of Clinical and Experimental Medicine, Prague, Czechia
  • Brown, Rhubell T., University of Alabama at Birmingham , Birmingham, Alabama, United States
  • Novak, Jan, University of Alabama at Birmingham , Birmingham, Alabama, United States
Background

IgA nephropathy (IgAN) is the most common primary glomerulonephritis, often leading to end-stage renal disease. The diagnosis and assessment of disease severity requires renal biopsy. Due to its inherent risks, non-invasive approaches would be very helpful.

Methods

We examined 94 patients with biopsy-proven IgAN who were assessed at the time of diagnosis for renal function, proteinuria, microscopic hematuria, and hypertension, and followed-up clinically since then. Using serum samples collected the time of diagnosis, we determined levels of galactose-deficient IgA1 (Gd-IgA1) and IgG autoantibodies specific for Gd-IgA1 (IgGAb) using lectin and immunodetection methods. Discriminant analysis and logistic regression model were used for statistical analyses.

Results

Clinical data (serum creatinine and eGFR), serum biochemical markers (Gd-IgA1, IgGAb) and histological scoring (Oxford MEST system) were used to develop a formula predicting the risk of disease progression at the time of biopsy. We observed higher levels of IgG autoantibodies in IgAN patients with progressive renal insufficiency at diagnosis compared to IgAN patients with stable renal function at the onset. We confirmed the association of IgG autoantibodies with the progression of Czech patients with IgAN.

Conclusion

Elevated serum levels of IgGAb may serve as marker of disease activity and/or decline of renal function and, thus, unfavorable predictor of disease progression in patients with IgAN. Longer clinical follow-up of this group and further evaluation of these results in larger cohorts are needed.
The authors (JN, CR, BAJ) have been supported in part by grants DK106341, DK079337, DK078244, DK082753, GM098539 from the National Institutes of Health and a gift from the IGA Nephropathy Foundation of America and the authors (DM, VT) by grant LH15168 and PRVOUK- P25/LF1/2.

Funding

  • Other NIH Support