Kidney Failure

When the kidneys fail—which can happen as a result of a number of different disorders, only some of which are primarily kidney diseases—waste products build up in the blood, causing serious complications. Acute kidney failure is the sudden loss of kidney function; chronic kidney failure develops gradually.

To function normally, the body really needs only one working kidney. As soon as the kidneys' filtering capacity falls much below 50 percent, however, problems begin to appear, worsening as filtering capacity drops. With special measures, such as dietary restriction and medication, however, children can survive even after kidney function has fallen to five or ten percent of normal.

WHEN SHOULD I SUSPECT THAT MY CHILD HAS KIDNEY FAILURE?
Acute kidney failure is usually a complication of some other serious illness. Generally, parents first notice that the child stops urinating or urinates very infrequently. Other symptoms include body swelling, drowsiness and irregular heartbeat.

The first signs of chronic kidney failure are usually loss of energy and easy fatigue. As the condition progresses, the child may lose appetite (particularly in the morning), pass less urine than usual and drink more fluids. The child's skin also may grow pale and develop a sallow, muddy appearance. Other symptoms include headaches, muscle cramps, nausea, weight loss, puffy face, bone or joint pain and bruised, dry or itchy skin. Children with chronic kidney failure also experience slowed growth.

WHAT CAUSES KIDNEY FAILURE?
Acute kidney failure may occur as a complication of shock, dehydration from diarrhea, persistent vomiting, blood loss, burns or trauma. Such failure is usually temporary and can be reversed by administration of fluids. Sometimes the problem originates when the kidney itself is damaged by disease or adverse reactions to some drugs.

Chronic kidney failure can be caused by chronic diseases of the kidneys, such as nephritis. It also may be due to chronic infection (pyelonephritis) often resulting from malformations of the kidneys and urinary tract. Kidney failure may be a complication of diabetes in older children and adolescents.

HOW IS KIDNEY FAILURE TREATED?
Treatment of acute kidney failure depends on the underlying cause. If it is caused by dehydration, the child receives large amounts of fluids. In all other cases, however, fluids must be restricted in order to prevent blood pressure elevation. The child usually is given diuretics to remove excess fluids from the body. Children with acute kidney failure are treated in a hospital.

Treatment of chronic kidney failure consists of eliminating the underlying disease whenever possible and preventing further loss of function. Children with chronic kidney failure may require drugs to correct their metabolism and treat high blood pressure, and they generally need to follow dietary restrictions.

Children with limited kidney function may need dialysis, a procedure in which the blood is circulated through a machine or fluids are filtered through the peritoneal membranes of the abdominal cavity. Dialysis is sometimes used as a temporary measure in acute kidney failure, but it may be required on a regular, long-term basis if the child's kidneys are permanently damaged.

Children with chronic, progressive kidney failure may be good candidates for kidney transplantation, in which a healthy kidney from a deceased donor or living relative takes the place of the failing kidneys. Kidney transplants are among the most common and successful transplant operations.

PREVENTING KIDNEY DISEASE
The following are some precautions you can take to prevent kidney disease:

• Prevent dehydration. Be sure a child with diarrhea or vomiting gets enough fluids.

• Control high blood pressure and diabetes, which may damage the kidneys.

• If your child has chronic kidney failure, take precautions to avoid other diseases or infections that may further strain the kidneys.

GETTING HELP
Call your doctor if your child:

• Passes urine less often than usual

• Develops swelling, especially of the face, hands and feet

Excerpt from THE DISNEY ENCYCLOPEDIA OF BABY & CHILD CARE, © 1995 DSH Communications, Inc. This material is based on current medical research and, to the best of the editors' knowledge and understanding, is accurate and valid. However the reader should not use information contained in this material to alter a medically prescribed regimen or as a form of self-treatment, without seeking the advice of a licensed physician.