What Causes Focal Segmental Glomerulosclerosis?
Focal segmental glomerulosclerosis is a kidney disorder in which scar tissue forms on the glomeruli. Unlike other forms of the condition, focal segmental glomerulosclerosis affects only some of the estimated one million glomeruli within each of the kidneys, and only small segments of each glomerulus are damaged. Glomeruli are part of the kidneys' filtration system, and scarring to this area causes permanent kidney damage, which eventually may lead to kidney failure. Many individuals with focal segmental glomerulosclerosis have no symptoms. When symptoms are present, they generally include swelling of the eyes, hands, feet, and abdomen, weight gain, and high blood pressure. Some patients may have protein in the urine, and high cholesterol is especially common. To diagnose this condition, doctors perform a biopsy on a small sample of tissue from the kidneys. An estimated 5,400 individuals in the United States are diagnosed with focal segmental glomerulosclerosis each year.
While many cases of focal segmental glomerulosclerosis have no known cause, doctors have identified possible causes for a type of this disorder known as secondary focal segmental glomerulosclerosis. This particular form of glomerulosclerosis develops due to an underlying medical condition. Some of the major conditions that cause this form of the disease are outlined below.