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.



For reasons not yet fully understood, doctors suspect obesity is strongly linked to the development of focal segmental glomerulosclerosis. Obese patients who have this disease may experience more swelling and weight gain. Doctors recommend losing weight as one of the major lifestyle modifications for patients with focal segmental glomerulosclerosis. Currently, patients are classified as obese if they have a body mass index of thirty or higher. To lose weight, patients with kidney disorders need to pay particular attention to their diets. In addition to eating more fruits and vegetables and avoiding fast food and fried foods, patients need to be especially mindful of their sodium and fluid intake. The patient’s nephrologist (kidney specialist) can recommend individualized limits for sodium, fluid, saturated fat, and cholesterol intake. Adhering to recommended limits may reduce the swelling patients experience, allowing them to be more comfortable. Specialists also recommend increased exercise to aid in weight loss. Patients with kidney disorders like focal segmental glomerulosclerosis who struggle with weight should always ask their specialist prior to beginning any new diet or fitness regimen.

Get familiar with more potential causes of focal segmental glomerulosclerosis now.



Diabetes is strongly associated with obesity, which as mentioned is a risk factor for focal segmental glomerulosclerosis. In addition, kidney damage is a frequent complication of diabetes. Thus, being a diabetes patient with focal segmental glomerulosclerosis can be particularly damaging to the kidneys, and patients with both conditions may have more severe symptoms. Diabetes develops when the body is unable to effectively use or produce insulin. As a result, patients have elevated blood sugar. Frequent symptoms of diabetes include excessive thirst, fatigue, weight loss, blurry vision, irritability, and wounds that are slow to heal. Diabetes patients must monitor their blood sugar daily, and doctors recommend making dietary changes and increasing exercise. When lifestyle modifications are insufficient, patients may need to use a combination of oral medicines and injections to manage diabetes. In the most advanced stages, patients will need to include daily insulin injections as well. Since these patients are at an elevated risk for kidney issues, they should have their kidney function tested according to their specialist’s instructions. They should also be aware of any changes in their urine or any lower back pain, as these may be signs of kidney issues and should be reported to their healthcare team.

Discover more causes of focal segmental glomerulosclerosis now.

Sickle Cell Anemia


Sickle cell anemia is a genetic form of anemia, and patients with this disorder do not have enough red blood cells to properly transport oxygen around the body. Common symptoms include swelling of the hands and feet, retinal damage, and episodes of severe pain that typically require hospitalization. Sickle cell anemia damages many organs in the body, including the spleen, kidneys, and liver. The damage to the kidneys from this condition may be a trigger for secondary focal segmental glomerulosclerosis. Patients are particularly vulnerable to pneumonia and other infections, and they may also experience leg ulcers, gallstones, pulmonary hypertension, and acute chest syndrome. To reduce the risk of organ damage and other serious complications, patients with sickle cell anemia will be monitored closely throughout their lives. Blood tests can be used to measure the function of the kidneys and other organs, and patients can use medications to reduce pain and minimize the likelihood of hospitalization.

Continue reading to reveal more focal segmental glomerulosclerosis causes now.

Inherited Abnormal Genes


Inherited abnormal genes have been identified as a cause in an especially rare form of glomerulosclerosis known as genetic or familial focal segmental glomerulosclerosis. Doctors normally suspect this type of the disease if a patient has several immediate or extended family members with symptoms of glomerulosclerosis. The condition can also develop in children whose parents are carriers. While the carriers do not have symptoms themselves, each parent (carrier) has an abnormal gene they then pass to their child. Researchers are currently investigating new genes that may play a role in this condition, and doctors can offer genetic testing for concerned patients and their families. Patients who choose to have this testing will often have genetic counseling before and after the test. If familial focal segmental glomerulosclerosis is identified, patients will be offered support services and other resources.

Get more details on the causes of focal segmental glomerulosclerosis now.

Other Kidney Diseases


In some cases, other kidney diseases have the potential to predispose patients to develop focal segmental glomerulosclerosis in the future. For example, certain congenital kidney defects are believed to contribute to a patient’s overall risk of focal segmental glomerulosclerosis. Patients with kidney reflux, a medical condition in which urine backs up into the kidneys, are also at a particularly elevated risk of developing focal segmental glomerulosclerosis. As a result of this information, it is clear patients who have other kidney diseases should ask their nephrologist about their individual risk of developing focal segmental glomerulosclerosis and about any steps they could take to reduce said risk.