Galactose-deficient immunoglobulin A1 (Gd-IgA1) deposition in the renal mesangium plays a role in the pathogenesis of IgA nephropathy.
To assess the serum Gd-IgA1 level in biopsy-proven IgA nephropathy cases on diagnosis and 3 months post treatment and its relation with histologic Oxford classification.
In this hospital-based prospective cohort study, 40 cases and 20 controls were enrolled. Serum samples of biopsy-proven IgA nephropathy cases collected on the day of biopsy and 3 months post treatment were evaluated. Solid-phase ELISA (enzyme-linked immunosorbent assay) was performed for assessment of Gd-IgA1 level. All renal biopsies were scored by using Oxford Classification (C-MEST score). The association of serum Gd-IgA1 levels with other established prognostic parameters was assessed. To estimate the prognostic value of markers, logistic regression analysis and Kruskal-Wallis ANOVA (analysis of variance) were used.
Significant difference was observed in the serum Gd-IgA1 level values in the IgA nephropathy cases and healthy controls (P = .001) at baseline. However, no significant correlation between serum Gd-IgA1 levels at baseline and 3 months of follow-up (P = .31) or between baseline levels and age, proteinuria, hematuria, or estimated glomerular filtration rate was noted. There was no significant correlation between C-MEST score and serum Gd-IgA1 levels at baseline (P > .05); however, the distribution of Gd-IgA1 at 3 months was found to differ significantly between different grades of S score (P = .008).
Serum Gd-IgA1 levels may be of utility in predicting disease progression in IgA nephropathy cases. Measurement of serum Gd-IgA1 levels for the diagnosis and prognosis of IgA nephropathy may preclude the need for invasive renal biopsies.
The authors have no relevant financial interest in the products or companies described in this article.