Understanding focal segmental glomerulosclerosis causes

Focal segmental glomerulosclerosis (FSGS) occurs when scar tissue develops on the small filtering units (glomeruli) inside the kidneys. Learning whether your diagnosis stems from primary, genetic, or secondary causes helps guide personalized discussions with your nephrologist. The liver & kidney hope foundation provides educational insights and community support for newly diagnosed patients and families.

Primary, genetic, and secondary causes

FSGS causes are generally categorized into three distinct types:

  • Primary (idiopathic): Driven by an immune system response or circulating permeability factor in the blood that harms the kidney filters without an identifiable single cause.
  • Genetic factors: Inherited genetic mutations, including APOL1 gene variants frequently seen in individuals of African ancestry, which substantially elevate susceptibility.
  • Secondary causes: Triggered by other medical conditions such as obesity, viral infections like HIV, sickle cell disease, reduced nephron mass (such as being born with one kidney or low birth weight), or toxic exposures like anabolic steroids.

Notice: The liver hope foundation is not a medical provider. Always consult your personal healthcare provider.

Recognizing signs, symptoms, and disease progression

FSGS frequently leads to nephrotic syndrome. Common symptoms include foamy or bubbly urine caused by protein leakage, fluid retention resulting in swelling of the legs, ankles, face, or around the eyes, unexpected weight gain, persistent fatigue, high blood pressure, and elevated cholesterol.

FSGS does not follow its own standalone staging system; instead, physicians monitor disease development using chronic kidney disease (CKD) stages 1 through 5 based on eGFR and urine protein levels. Seek urgent medical attention if you experience sudden shortness of breath, one-sided leg pain or swelling (which can indicate a blood clot), signs of infection, or sudden severe fluid retention.

Empowering resources and community guidance

Navigating an FSGS diagnosis begins with asking your nephrologist whether genetic testing or specific biomarker evaluation is suitable for your situation. Clarifying the origin of FSGS can directly influence your treatment strategy.

Access our free 22-page educational materials, including the FSGS Complete Guide, interactive worksheets, and companion booklets on nephrotic syndrome and chronic kidney disease. Our foundation also connects patients and families to peer support groups, local chapters, and trusted advocacy networks like NephCure to ensure no one walks this journey alone.