Long term, children can relapse several years after having no symptoms; though after 2 years, the risk is significantly lower.In most children with minimal change disease, particularly among those who respond typically, there is minimal to no permanent damage observed in their kidneys. Complications primarily arise from the side effects of therapy. Prolonged use of corticosteroids can lead to immunosuppression (leading to infection), growth complications, weight gain. Adults
While most adults diagnosed with minimal change disease  respond to corticosteroids, 25% fail to respond after 3–4 months of corticosteroid therapy; it is possible that these patients were incorrectly diagnosed, and do not have minimal change disease. Adults with MCD tend to respond more slowly to corticosteroid treatment, taking up to 3 or 4 months, than children do. Data in adults is less complete than for children, but relapses are fairly frequent with 56–76% of patients relapsing and needing further treatment with immunosuppressants such as ciclosporin, tacrolimus, mycophenolate, and rituximab. There is little evidence to support the use of azathioprine for MCD.As in children, complications primarily arise from the side effects of therapy. Prolonged use of corticosteroids can lead to immunosuppression (leading to infection), growth complications, weight gain. Epidemiology
Minimal change disease is most common in very young children but can occur in older children and adults.It is by far the most common cause of nephrotic syndrome in children, accounting for 70–90% of children >1 year of age. After puberty, it is caused by minimal change disease about half the time.
Data from a longitudinal study (Nephrotic Syndrome Study Network – NEPTUNE) published in 2022 suggested that up to 29% of biopsy-confirmed,  mixed pediatric and adult minimal change disease cases exhibited serum autoantibodies against nephrin, a structural protein located in the podocyte slit diaphragm.There has been discussion of B cell involvement in nephrotic syndrome, especially minimal change disease due to the success of immunotherapy that target both B and T cells, increased markers for B cell activation during a relapse of minimal change disease, and alterations in B cell sub-classes during minimal change disease remission. This hypothesis is supported by recent findings of anti-nephrin antibodies isolated in minimal change disease. Edema
When albumin is excreted in the urine, its serum (blood) concentration decreases. Consequently, the plasma oncotic pressure reduces relative to the interstitial tissue. The subsequent movement of fluid from the vascular compartment to the interstitial compartment manifests as the soft tissue swelling referred to as edema. This fluid collects most commonly in the feet and legs, in response to gravity, particularly in those with poorly functioning valves. In severe cases, fluid can shift into the peritoneal cavity (abdomen) and cause ascites. As a result of the excess fluid, individuals with minimal change disease often gain weight, as they are excreting less water in the urine, and experience fatigue. Diagnosis
As minimal change disease is a subset of nephrotic syndrome, diagnosis involves looking for a combination of edema, high amounts of protein in urine, low albumin and high serum cholesterol.