Focal Segmental Glomerulosclerosis, or FSGS, is a disease characterized by scarring that damages the glomeruli, the tiny filtering units in the kidneys responsible for cleaning the blood. This damage disrupts the kidney’s ability to function, often leading to protein loss in the urine. The progression of FSGS and its impact on life expectancy varies considerably from one person to another based on individual factors and clinical measurements.
General Prognosis and Survival Statistics
When discussing the prognosis of FSGS, specialists refer to “renal survival.” This term describes the length of time until the disease advances to end-stage renal disease (ESRD), the point at which the kidneys can no longer function on their own. At this stage, life-sustaining treatments like dialysis or a kidney transplant become necessary. The time it takes to reach ESRD can range from two years to more than 20 years.
General statistics illustrate this variability. Some studies indicate that for patients who are not responsive to treatment, the progression to ESRD can occur within an average of six to eight years. Other long-term studies have calculated actuarial survival, showing a 75% survival rate at 5 years, which drops to 50% at 10 years and 38% at 15 years post-diagnosis. An individual’s journey with FSGS is shaped by a personal set of clinical and biological markers that define their unique prognosis.
Factors That Influence Life Expectancy
The prognosis for an individual with FSGS is determined by a combination of specific clinical findings, many of which are identified at the time of diagnosis. The most predictive factors include:
- The level of proteinuria, which is the amount of protein in the urine. Patients with nephrotic-range proteinuria (losing more than 3.5 grams per day) have a greater than 50% chance of progressing to ESRD within 10 years. Those with lower levels face a much lower risk, with about 15% progressing in the same timeframe.
- The kidney’s filtering capacity at diagnosis, measured as the estimated Glomerular Filtration Rate (eGFR). A lower eGFR signifies that the kidneys have already sustained damage and is associated with poorer long-term renal survival.
- The specific subtype of FSGS, identified through a kidney biopsy. The “collapsing variant” is the most rapidly progressing form, often leading to the need for dialysis within one to two years. Conversely, the “tip lesion” variant is associated with a much better outcome.
- The underlying cause of the disease. Primary FSGS occurs without an identifiable cause, while secondary FSGS can be triggered by other conditions. Treating the underlying cause in secondary FSGS can sometimes slow the progression of kidney damage.
- The response to initial treatment. Achieving complete or partial remission—a significant reduction in proteinuria—is linked to an 80% kidney survival rate at 10 years, compared to about 50% for those who do not respond to therapy.
How Treatment Impacts Prognosis
The management of FSGS is centered on reducing the amount of protein lost in the urine and preserving existing kidney function. While there is no definitive cure, available treatments can slow the scarring process and alter the disease’s course. Successfully managing symptoms and slowing progression can lead to a better quality of life and improved long-term outcomes.
The first line of defense often involves corticosteroids to decrease proteinuria. For patients who do not respond to steroids or who experience relapses, other immunosuppressive medications are introduced. These can include calcineurin inhibitors like cyclosporine and tacrolimus, or drugs such as mycophenolate mofetil. The goal of this therapy is to achieve remission, which is the most favorable prognostic factor for maintaining long-term kidney function.
In addition to targeting the immune system, controlling blood pressure is a standard part of the treatment plan. Medications like ACE inhibitors and angiotensin II receptor blockers (ARBs) are commonly prescribed. These drugs help protect the kidneys by lowering pressure inside the glomeruli, which reduces protein leakage, and are beneficial even for patients without high blood pressure.
Life Expectancy with Kidney Failure and Transplantation
When FSGS progresses to ESRD, treatments are available to sustain life. The two primary options are dialysis and kidney transplantation. Dialysis is a procedure that artificially performs the function of the kidneys by filtering waste from the blood. Studies show that the median survival duration on dialysis for patients with FSGS is approximately 6.9 years, with survival rates of 64% at five years and 28% at ten years.
Kidney transplantation is considered the most effective treatment for ESRD, offering the potential for a longer life with a higher quality compared to dialysis. For FSGS patients who receive a kidney transplant, patient survival rates are high, with studies reporting 94% survival at five years and 83% at ten years post-transplant. This demonstrates that a successful transplant can extend life expectancy for individuals whose kidneys have failed.
A known complication of transplantation for FSGS is the possibility of the disease recurring in the new kidney, with a risk ranging from 20% to 50%. While recurrence can lead to the loss of the transplanted kidney, it is a risk that medical teams are prepared to manage. Over half of patients who experience recurrence may lose their new kidney within five years, but many others maintain function with treatment.