Complement factor H-related proteins in IgA nephropathy-sometimes a gentle nudge does the trick.

Complement activation probably contributes to glomerular inflammation and damage in IgA nephropathy. In this issue, 2 groups report that levels of factor H-related protein 1 are elevated in patients with IgA nephropathy and correlate with disease progression. These studies provide new evidence that the complement cascade is important to the pathogenesis of this disease. These results also suggest that factor H-related protein 1 levels may be useful for identifying those patients at high risk of disease progression.