What is the diagnostic value of detecting anti-PLA2R?

The serological determination of IgG autoantibodies against PLA2R, which requires only a blood sample, is easy to perform and presents a non-invasive alternative to the common biopsy. Anti-PLA2R autoantibodies are a highly specific and sensitive marker for primary MN. They can be found in the serum of approximately 70 % of patients with primary MN. In patients with secondary MN or in healthy individuals anti-PLA2R antibodies can be detected only in rare exceptions.

Additionally to its usage in differentiation of primary and secondary MN, the anti-PLA2R titer reveals a high predictive value for:

Disease evaluation
Anti-PLA2R autoantibody titers correlate with disease activity (proteinuria). High titers are associated with a severe course of primary MN.1,2

Therapy monitoring
The anti-PLA2R autoantibody titer decreases in patients undergoing successful immunosuppressive therapy. Hereby, the titer decrease precedes the decline in proteinuria. A relapse of disease is associated with a recurrence of the antibodies.3,4 Furthermore, a high anti-PLA2R titer was identified as a considerable risk factor for primary MN patients to not achieve a remission of proteinuria.4

Risk assessment
Up to 40 % of patients with primary MN experience a relapse after kidney transplantation.5 This risk is particularly high if anti-PLA2R autoantibodies are persistently found during the six months after organ transplantation.6 Therefore, the titer can be useful to assess the necessity and intensity of an immunosuppressive therapy after transplantation to avoid relapses.