Focal segmental glomerulosclerosis (FSGS) is a cause of nephrotic syndrome in children and adolescents, as well as a leading cause of kidney failure in adults. It is also known as 'focal glomerular sclerosis' or 'focal nodular glomerulosclerosis.' It accounts for about a sixth of the cases of nephrotic syndrome. (Minimal change disease (MCD) is by far the most common cause of nephrotic syndrome in children: MCD and primary FSGS may have a similar cause.) Focal segmental glomerulosclerosis (FSGS) is a cause of nephrotic syndrome in children and adolescents, as well as a leading cause of kidney failure in adults. It is also known as 'focal glomerular sclerosis' or 'focal nodular glomerulosclerosis.' It accounts for about a sixth of the cases of nephrotic syndrome. (Minimal change disease (MCD) is by far the most common cause of nephrotic syndrome in children: MCD and primary FSGS may have a similar cause.)