Focal Segmental Glomerulosclerosis (FSGS)
FSGS is a term that describes a pattern of scarring in the kidneys. This scarring can be seen on a biopsy in patients with increased levels of protein in their urine.
Medically reviewed by Dr. Kirk Campbell, M.D.
Who Gets FSGS
FSGS occurs in all age groups and among people from all backgrounds. There are some notable risk factors. FSGS is more common among people with:
– A family history of FSGS
– African ancestry
– Low birth weight
– Obesity
– Premature birth
– Viral infections, including HIV
Types of FSGS
There are four types of FSGS as defined by the 2021 Kidney Disease: Improving Global Outcomes Glomerular Diseases Work Group (KDIGO) guidelines.
Primary
the most aggressive form, caused by a defect in the immune system
Secondary
from an identifiable cause such as a viral infection or drug
Genetic
caused by a change in your genes
Unknown cause
cause not yet understood
Signs and Symptoms
All forms of FSGS cause high levels of protein in the urine. This increased protein can cause the urine to appear frothy or foamy.
Other common signs of FSGS include:
- Fluid retention and swelling in the legs, ankles, and around the eyes
- Weight gain from fluid buildup
If the overall kidney function deteriorates significantly, you may also experience additional symptoms such as:
- Decreased urine output (producing less urine)
- Fatigue
- Nausea
- Poor appetite
Diagnosing FSGS
Doctors diagnose FSGS using a kidney biopsy.
During the procedure, your doctor removes a sample of kidney tissue and studies it under a microscope. Your doctor looks for tissue scarring on some but not all (focal) urine filtering units in the kidney. These units are called glomeruli. Scarring affects only a portion (segmental) of the glomeruli.
Your Treatment Options
Your doctor recommends treatment based on your:
- Kidney function
- Protein in the urine
- Type of FSGS
If you have primary FSGS, your doctor is likely to prescribe medicines that modify your immune system. These include:
- Steroids
- Medicines that target T and B cell function
Clinical trials are another treatment option.
Your doctor helps you find the right study for you. These trials test more targeted treatments with potentially lower risks of side effects.
Some clinical trials enroll patients, based on their genetic testing results, to test the effectiveness of precision-based therapies targeted to specific genetic changes. Knowing your genetic test results is important because patients with genetic FSGS generally do not show a meaningful clinical response to immunosuppressive medicines that suppress the immune response to reduce inflammation.
Tips For Living With FSGS
Patients with FSGS benefit from supportive measures including:
Exercise
Regular, moderate activity helps manage your blood pressure and weight and improves your overall well-being.
Prescription Regimen
Follow your doctor’s instructions and take your medicines as prescribed.
Regular Check-Ups
See your doctor as scheduled to monitor your kidney function and quickly address any changes.
Kidney Transplant and Recurrence in FSGS
1
Genetic Testing
Genetic testing can help you understand your risk for needing a kidney transplant and your prognosis after a transplant.
2
Recurrence
Between 30% and 40% of FSGS patients have a recurrence of FSGS after a kidney transplant.
3
Kidney Failure
This recurrence can cause your new kidney to fail. Kidney failure often requires maintenance dialysis.
4
Genetic FSGS
If you are diagnosed with genetic FSGS, you have a much lower risk of post-transplant FSGS recurrence.