PLA2R1 and idiopathic membranous glomerulonephritis: The diagnostic test accuracy of circulating anti-PLA2R autoantibody in differentiating primary from secondary membranous GN is acceptable, with reported test sensitivity of 65% (63–67%), specificity of 97% (97–98%), positive likelihood ratio of 15.65 (9.95–24.62), and negative likelihood ratio of 0.37 (0.32–0.42) (155).