Nephrotic syndrome is caused by damage to the tiny blood vessels in the kidney that filter waste and excess water from the blood.

Many conditions and diseases can cause nephrotic syndrome, including:

• Minimal change disease (also called nil disease), a type of kidney disease. The cause of minimal change disease is unknown, but it causes most of the cases of nephrotic syndrome in children.¹
• Membranous glomerulopathy and focal segmental glomerulosclerosis, which are two other diseases of the kidney. Both of these diseases affect the glomeruli. The glomeruli help filter waste out of your blood. In focal segmental glomerulosclerosis, some of the parts of the glomeruli have scar tissue. This can affect how they filter the blood. In membranous glomerulopathy, the tissue wall (membrane) that separates blood and urine and acts as a filter in your kidney becomes thickened and damaged.
• Diabetes and lupus. Diabetes is the most common cause of nephrotic syndrome in adults in the United States.²
• Infections, such as HIV, hepatitis B, hepatitis C, syphilis, malaria, tuberculosis, or post-streptococcal glomerulonephritis.
• Cancer, such as breast cancer, lung cancer, Hodgkin's lymphoma, or multiple myeloma.
• Medicines, such as nonsteroidal anti-inflammatory drugs, penicillamine, gold therapy, or captopril.
• Illegal drugs, such as heroin.
• Conditions such as preeclampsia, chronic graft rejection following an organ transplant, and allergic reactions to bee stings.
• Unknown (idiopathic) factors.