Congenital nephrotic syndrome

Definition

Congenital nephrotic syndrome is disorder passed down through families in which a baby develops protein in the urine and swelling of the body. Congenital means it is present from birth.

See also: Nephrotic syndrome

Alternative Names

Nephrotic syndrome - congenital

Causes, incidence, and risk factors

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 inherited, which means it is passed down through families.

Children with this disorder have an abnormal form of a protein called nephrin, which is found in the kidney.

Symptoms

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

Signs and tests

An ultrasound done on the pregnant mother before birth may show a larger-than-normal placenta. The placenta is the organ that develops during pregnancy to feed the developing baby.

Pregnant mothers may have a screening test done during pregnancy to check for this condition. The test looks for higher-than-normal levels of alpha-fetoprotein in sample of amniotic fluid. Genetic tests should be used to confirm the diagnosis if the screening test is positive.

After birth, the infant will show signs of severe fluid retention and generalized swelling. The health care provider will hear abnormal sounds when listening to the baby's heart and lungs with a stethoscope. Blood pressure may be high. There may be 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.

Treatment

Early and aggressive treatment is needed to control the disorder.

Treatment may involve:

• Antibiotics to control infections
• Blood pressure medicines called ACE inhibitors
• Diuretics ("water pills") to eliminate excess fluid
• Nonsteroidal anti-inflammatory drugs (NSAIDs) such as indomethacin to slow protein build up in the urine

Fluids may be restricted to help control swelling.

Removal of the kidneys, dialysis, and kidney transplant may be recommended.

Expectations (prognosis)

The disorder commonly results in infection, malnutrition, and kidney failure. It can often lead to death by 5 years of age, and many children die within the first year. Congenital nephrotic syndrome may be successfully controlled in some cases with early and aggressive treatment, including early kidney transplantation.

Complications

• Acute kidney failure
• Blood clots
• Chronic kidney failure
• End-stage kidney disease
• Frequent, severe infections
• Malnutrition and related diseases

Calling your health care provider

Call your health care provider if your child has symptoms of congenital nephrotic syndrome.

References

Nephrotic Syndrome. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 18th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap. 527.