Unique laboratory tests for Membranoproliferative glomerulonephritis
Are there any unique laboratory tests that are relevant to patients with Membranoproliferative glomerulonephritis?
Mutations in the alternative pathway of complement proteins or detectable levels of the activity of C3 nephritic factor, an IgM autoantibody to the alternate pathway C3 convertase (C3bBb), are more common in type II disease—that is, in up to 80% of patients, compared with 20% to 25% of patients with types I or III disease.
C3 nephritic factor can be measured in a hemolytic or solid-phase assay. This autoantibody is also detectable in up to 50% of patients with secondary forms of Membranoproliferative glomerulonephritis.
Patients with type III Membranoproliferative glomerulonephritis may have a nephritic factor of the terminal complement pathway that stabilizes properdin-dependent C5 convertase.