A 48-year-old woman with newly diagnosed nephrotic syndrome undergoes biopsy showing diffuse GBM thickening with subepithelial deposits. Serum testing for IgG antibodies against the phospholipase A2 receptor (PLA2R) on podocytes returns positive. This result supports which diagnosis?

• A Secondary membranous nephropathy due to systemic lupus erythematosus
• B Diabetic nodular glomerulosclerosis
• C Membranoproliferative glomerulonephritis
• D Primary (idiopathic) membranous nephropathy ✓

Explanation

Circulating autoantibodies against the M-type phospholipase A2 receptor, a podocyte transmembrane antigen, are found in roughly 70 to 80 percent of patients with primary membranous nephropathy and are considered diagnostic of the idiopathic form. Anti-PLA2R positivity essentially excludes a secondary cause such as lupus, hepatitis D, malignancy, or drugs, which produce membranous-pattern injury through different antigens.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.