Causes

Often, membranous nephropathy results from some type of autoimmune activity. Your body's immune system mistakes healthy tissue as foreign and attacks it with substances called autoantibodies. These autoantibodies target certain proteins located in the kidney's filtering systems (glomeruli). This is known as primary membranous nephropathy.

Sometimes membranous nephropathy is brought on by other causes. When this happens, it's called secondary membranous nephropathy. Causes may include:

• Autoimmune disease, such as lupus erythematosus
• Infection with hepatitis B, hepatitis C or syphilis
• Certain medications, such as gold salts and nonsteroidal anti-inflammatory drugs
• Solid cancerous tumors or blood cancers

Membranous nephropathy may also occur along with other kidney diseases, such as diabetic nephropathy and rapidly progressive (crescentic) glomerulonephritis.