A 58-year-old man presents with nephrotic-range proteinuria and normal renal function. Renal biopsy shows thickened GBM with subepithelial deposits. Serum testing shows high titers of antibodies against the phospholipase A2 receptor (PLA2R). Which statement best explains the significance of this finding?
- A It confirms a secondary form of membranous nephropathy due to an occult malignancy
- B It indicates lupus nephritis class V and mandates antinuclear antibody testing
- C It supports idiopathic (primary) membranous nephropathy and predicts a lower likelihood of spontaneous remission at high titers ✓
- D It identifies hepatitis B virus as the causative antigen in this patient
Correct answer: C. It supports idiopathic (primary) membranous nephropathy and predicts a lower likelihood of spontaneous remission at high titers
Explanation
PLA2R is expressed on podocytes and is the major target antigen in primary membranous nephropathy, detected in about 70 to 80 percent of cases. High antibody titers correlate with active disease and lower rates of spontaneous remission, and falling titers predict remission after therapy. Secondary membranous nephropathy from malignancy, hepatitis C, or drugs is typically PLA2R negative, which kills options A, B, and D.
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.