Congenital nephrotic syndrome
Congenital nephrotic syndrome is a 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. However, this group of disorders also includes nephrotic syndrome that occurs in the first 3 months of life.
Nephrotic syndrome - congenital
Congenital nephrotic syndrome is a very rare form of nephrotic syndrome. It occurs mostly 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. The kidney's filters (glomeruli) need this protein to function normally.
Symptoms of nephrotic syndrome include:
- Decreased urine output
- Foamy appearance of urine
- Low birth weight
- Poor appetite
- Swelling (total body)
Exams and Tests
An ultrasound done on the pregnant mother may show a larger-than-normal placenta. The placenta is the organ that develops during pregnancy to feed the growing 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 a sample of amniotic fluid. Genetic tests are then used to confirm the diagnosis if the screening test is positive.
After birth, the infant will show signs of severe fluid retention and 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.
Early and aggressive treatment is needed to control this disorder.
Treatment may involve:
- Antibiotics to control infections
- Blood pressure medicines called angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) to reduce the amount of protein leaking into the urine
- Diuretics ("water pills") to remove excess fluid
- Nonsteroidal anti-inflammatory drugs (NSAIDs), such as indomethacin, to reduce the amount of protein leaking into the urine
Fluids may be limited to help control swelling.
The provider may recommend removing the kidneys to stop protein loss. This may be followed by dialysis or a kidney transplant.
The disorder often leads to infection, malnutrition, and kidney failure. It can lead to death by age 5, and many children die within the first year. Congenital nephrotic syndrome may be controlled in some cases with early and aggressive treatment, including an early kidney transplant.
Complications of this condition include:
- Acute kidney failure
- Blood clots
- Chronic kidney failure
- End-stage kidney disease
- Frequent, severe infections
- Malnutrition and related diseases
When to Contact a Medical Professional
Call your provider if your child has symptoms of congenital nephrotic syndrome.
Bakkaloglu SA, Schaefer F. Diseases of the kidney and urinary tract in children. In: Taal MW, Chertow GM, Marsden PA, Skorecki K, Yu ASL, Brenner BM, eds. Brenner and Rector's The Kidney. 9th ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 75.
Jalanko H, Kaariainen H. Nephrotic disorders. In: Rimoin D, Pyeritz RE, Korf B, eds. Emery and Rimoin's Principles and Practice of Medical Genetics. 6th ed. Philadelphia, PA: Elsevier; 2013:chap 64.