Polycystic Kidney Disease

Polycystic kidney disease (PKD) is an inherited condition that results in abnormally formed kidneys. It also causes other abnormalities throughout the body.

What is going on in the body?

Polycystic kidney disease has three forms: infantile, childhood, and adult. The forms are named this way because of the time during a person's life when symptoms begin. The earlier symptoms begin, the more severe the disease usually is. All three forms are inherited from either one or both parents, depending on the type of PKD.

Polycystic kidney disease results in malformed kidneys, which are filled with small sacs, or cysts, instead of normal kidney tissue. This leads to kidney problems including kidney failure, which can lead to death. Abnormalities in other areas of the body may also occur.

What are the causes and risks of the disease?

All forms of polycystic kidney disease are inherited. In order for a child to inherit the infantile or childhood form of PKD, he or she must receive an abnormal gene from both parents. This form of inheritance is called autosomal recessive. Each parent has one abnormal gene and one normal gene, but neither parent has the disease itself. However, the parents may both pass the abnormal gene on to their children, causing the child to have PKD.

The adult form of PKD only requires one abnormal gene, which can come from either parent. This type of inheritance is called autosomal dominant. In this situation, the parent with the abnormal gene has PKD. Because he or she also has a normal gene, however, not all of the person's children are affected.