Congenital nephrotic syndrome is an inherited disorder characterized by protein in the urine and swelling of the body (see also Nephrotic syndrome).

Congenital nephrotic syndrome is a very rare form of nephrotic syndrome. It occurs primarily in families of Finnish origin and develops shortly after birth. It is an inherited disorder. The condition is caused by a protein called nephrin which is found in the kidney and is abnormal in children with the disorder.

Proteins and fats are excreted in the urine, and there is an abnormally high fat level in the blood. Swelling occurs from the effects of kidney failure, combined with the loss of blood protein. This is because proteins in the blood normally keep fluids in the blood stream, and when protein level is low, the fluid can leak into the body tissues.

Some of the proteins lost in the urine are immune system antibodies that fight infections. The disorder commonly results in infection, malnutrition, and kidney failure. It can often lead to death by 5 years of age.

• Low birth weight
• Large placenta
• Swelling (total body)
• Decreased urine output
• Foamy appearance of urine
• Poor appetite
• Cough

An examination reveals massive fluid retention and generalized swelling. Abnormal sounds are heard when listening to the heart and lungs with a stethoscope. Blood pressure may be high. The patient may have signs of malnutrition.

A urinalysis reveals large amounts of protein and the presence of fat in the urine. Total protein in the blood may be low. The disorder can be screened for during pregnancy by finding elevated levels of alpha-fetoprotein on a routine sampling of amniotic fluid. Genetic tests should be used to confirm the diagnosis, if the screening test is positive.

Frequent infections may occur over the course of the disease.