Most parents look forward to the day when their child is completely toilet-trained and in full control of his or her excretory bodily functions. But some kids may continue to have problems with their urination patterns. They may use the bathroom more often than normal or even wet the bed. If a visit to the pediatrician reveals the presence of proteins in the child’s urine, it may be an indication that the youngster’s kidneys are not functioning properly – which may be a precursor for kidney disease.
When the blood moves through the kidneys, salt and waste fluids are filtered out and excreted by the body in the form of urine. Proteins are too big to get filtered by the kidneys because they are designed to remain in the body. However, if an inordinate amount of proteins are present in the urine, this is usually a sign that the kidneys are not working. This condition is called proteinuria.
Proteins are the basic structural molecules of the body’s tissues. All of the organs and muscles in the body as well as its immune system are made up of proteins. These proteins are also needed to produce hormones, antibodies, blood clotting factors, and enzymes. Good sources of protein are found in foods like meat, fish, poultry, milk, eggs, cheese, chickpeas, beans, soybeans, navy beans, and pinto beans.
There are numerous conditions and diseases that can cause proteinuria. Some of the most common include diabetes, high blood pressure, and Epstein-Barr virus (a common virus which can lead to mononucleosis). It is also possible for proteinuria to result from kidney disease, kidney stones, a urinary tract infection, or lupus (an autoimmune disease where the body attacks healthy tissues and organs).
A child who suffers from kidney disease may show symptoms like swelling in the face, ankles, feet, or around the eyes (which is also known as edema). There is often an increased frequency of urination which may be accompanied by a burning sensation, and there could also be traces of blood in the urine. The afflicted child may not be able to control his or her urination, which can frequently lead to bedwetting. He or she might also suffer from fever or high blood pressure (hypertension).
Parents should watch their children for warning signs of proteinuria like swelling of the face and limbs or increased urination frequency. If a parent suspects that his or her child may be suffering from kidney disease, a doctor must be consulted immediately. If treatment for kidney disease is delayed, the ailment may become more severe.
To diagnose proteinuria, a 24-hour urine sample of the child is taken where the child urinates into a container instead of the toilet for 24 hours. Then a dipstick test is administered using a special paper that can detect proteins in the urine sample. Blood tests may also be conducted to measure protein levels. A shortage of proteins in the blood may indicate that the kidneys are not filtering efficiently.
Orthostatic proteinuria is a type of proteinuria where protein travels into the urine only when a child is standing up; this does not occur when the child is sitting or sleeping. So even though the kidneys are not damaged, protein is excreted in the urine during the day when the child is active but not at night. Orthostatic proteinuria can be diagnosed by taking two urine samples: one when the child wakes up in the morning and another made up of the urine that is collected throughout the day. If the morning sample does not show any protein content but the subsequent sample does, then the child has orthostatic proteinuria.
Treatment is not necessary for orthostatic proteinuria or if there is only a small trace of protein found in the urine sample, though a doctor might reanalyze the child’s urine after a few months to check for an increase in protein levels. If there is a substantial amount of protein in the urine, then the physician may refer the patient to a nephrologist, a kidney specialist. The nephrologist will likely perform a biopsy to obtain a sample of kidney tissue for analysis, and then he or she will formulate a treatment plan depending on the biopsy results.
Decreasing salt intake may be advised in order to reduce inflammation of the kidneys, which may contribute to their inefficient filtering of proteins. Anti-inflammatory medications such as cytotoxic agents or corticosteroids may be recommended to help shrink kidney swelling. These medicines are usually prescribed in high doses initially, but the dosages are gradually decreased over the subsequent weeks or months. Sometimes, children may take these medications for a number of years. If the condition does not respond to anti-inflammatories, angiotensin converting enzyme (ACE) inhibitors may be prescribed in order to combat hypertension, a condition that can be the cause of proteinuria.
Proteinuria can only be “cured” by addressing the underlying disease causing the condition. However, proteinuria commonly goes away on its own, and medications can often control the symptoms of the condition and lessen the presence of proteins in urine.
For more information regarding kidney disease that causes proteinuria in children, parents can contact the American Society of Pediatric Nephrology, the American Kidney Fund, or the National Kidney Foundation.