Childhood nephrotic syndrome
Nephrotic syndrome is a group of symptoms that point to kidney problems. Nephrotic syndrome can happen in adults, but occurs frequently in children. Typically, childhood nephrotic syndrome is discovered when a child is between the ages of 18 months and five years. Boys are diagnosed more often than girls.
A diagnosis of childhood nephrotic syndrome indicates that a child's glomeruli, the kidneys’ tiny filtering units, have been damaged from infection or inflammation. In healthy kidneys, the glomeruli filter excess water, wastes and dissolved substances such as minerals from the blood. Damaged glomeruli, by contrast, may allow blood and protein to leak into the urine.
What to look for
A child with nephrotic syndrome will urinate less frequently and the urine that is produced may contain high levels of protein, a condition called proteinuria. This causes low blood protein levels and water retention in body tissues. Sometimes signs of proteinuria can be weight gain from the water retention, and edema (swelling) of the face, hands, feet, ankles and abdomen.
Diagnosing childhood nephrotic syndrome
Determining if a child has nephrotic syndrome can be done by looking for protein in the urine. A sample may be tested at the doctor’s office, or the child may be asked to collect urine over a period of 24 hours for more precise measurements.
The physician may take a blood sample for analysis. Because kidneys remove wastes such as urea nitrogen and creatinine, increased levels of these substances in the blood can indicate kidney damage. Fortunately, most children with nephrotic syndrome will not have permanent kidney damage.
In some cases, a kidney biopsy is recommended to allow the doctor to examine a small piece of tissue under a microscope to determine the cause of the nephrotic syndrome.
In most cases, the root of the diagnosis will be “minimal change disease.” A child with this form of nephrotic syndrome will have kidney biopsy results that appear normal or close to normal. The cause of minimal change disease is unknown.
In about 20% of nephrotic syndrome cases, the kidney biopsy shows scarring of or deposits in the glomeruli. Most often, this kidney damage is caused by focal segmental glomerulosclerosis (FSGS) or membranoproliferative glomerulonephritis (MPGN).
Treating childhood nephrotic syndrome
The treatment for childhood nephrotic syndrome depends on the cause. Minimal change disease is often treated with prednisone, a medicine that stops the leakage of protein into the urine. Once the urine is protein free, the prednisone dose can be gradually reduced and finally discontinued. While relapses are common, especially after a viral infection, usually all incidences of this type of nephrotic syndrome will end by the time a child reaches adulthood.
A doctor may also prescribe a diuretic. Diuretics help the child urinate more frequently and reduce edema. Limiting the amount of fluids and salt a child consumes can also decrease water retention.
If the diagnosis is either FSGS or MPGN, angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) are two types of medication that work to reduce proteinuria and prevent kidney damage.
Childhood nephrotic syndrome is an indicator of kidney problems and is typically diagnosed in children of 18 months-five years of age. When a child shows signs of this condition, it’s best to see the doctor immediately for a diagnosis and timely treatments to prevent or minimize permanent injury to the kidneys.