Polycystic kidney disease, also referred to as PKD, is an inherited disease, characterized by numerous fluid filled cysts growing in the kidneys. The cysts formed can gradually replace most of the kidneys' mass, thus inhibiting kidney function. The later stages of the disease are most commonly marked by kidney failure.
Kidney failure calls for either dialysis or transplantation of the affected kidney in the patient. Polycystic kidney disease will eventually progress to kidney failure in almost half of the affected patients. Complications include forming of cysts in the liver. PKD can also have an adverse impact on other organs like the blood vessels in the brain and the heart.
In fact, these complications are what often assist doctors in identifying a case of PKD and allows them to differentiate it from the simple and harmless cysts that form quite often with advancing age. Another complication of kidney cysts is that the cysts may become infected. This is a very painful condition to be in. Around 500,000 people in the US develop polycystic kidney disease, with it being the fourth leading cause of kidney failure. It is also the most common type of inherited disease in the US.
Types of Polycystic Kidney Disease
Medical science defines two main inherited types, and one non-inherited type of PKD, as explained below.
1. Autosomal dominant PKD
This is an inherited form of the disease, and it accounts for 90% of PKD cases. The meaning of the 'autosomal dominant' is that, if one of the parents is a PKD patient, there is a 50% chance of a child getting the PKD too.
2. Autosomal recessive PKD
This too is an inherited type of the disease, although it occurs rarely. In this form, a child can have the disease although his/her parents may not have it. This comes about when both the parents have the recessive allele (or, in other words, both are carriers), and if the child should get both the recessive alleles, the child will get the disease.
3. Acquired cystic kidney disease, ACKD
This is related to long-term problems of the kidneys, occurring especially in people who have experienced kidney failure and have thus been on dialysis for a long time. This is the reason ACKD occurs in old people. This type of PKD c- since it is not caused by a genetic condition - is not inheritable.
Now, let us look at the symptoms of PKD.
Polycystic Renal Disease Symptoms
There are several symptoms exhibited by this disorder. An individual afflicted with PKD may or may not experience all the symptoms mentioned below. Here are a few of the most common symptoms of PKD:
- Repeated infections of the kidneys
- Pain in the sides and back
- Infections of the urinary tract
- Blood being passed in the urine
- Cysts in the pancreas and the liver
- Abnormalities in the heart valves
- Stones in the kidneys
- Brain aneurysms
- High blood pressure
Autosomal recessive PKD is usually also referred to as 'infantile PKD'. Kidney failure usually occurs within a few years of birth in children with this form of PKD. The severity of the illness, however, varies. Babies that are born with a severe form of the disease usually do not survive longer than a few hours, or at the most a few days. Children that have the infantile type may have enough kidney function to live normally for a few years. Those who have the juvenile type of the disease can live up to their teens, and even their twenties, although they generally develop liver problems too, in the later stages of the disease.
In addition to the list of symptoms given above, children affected with autosomal recessive PKD also have low blood-cell counts, hemorrhoids, and varicose veins. Since early physical development is dependent on kidney function, children who suffer from autosomal recessive PKD are generally smaller in size than normal children.
Generally, this disease occurs in a mild form, causing only minimal problems. Around 60 percent of those afflicted with it develop high blood pressure, which can be treated with drugs. Around 50 percent of people who have polycystic kidney disease develop failure of the kidneys by the time they are 60 years of age, and thus will require dialysis and the transplantation of kidneys. This renal disorder is usually worse in those who have sickle cell disease, African Americans, and in men.