Polycystic Kidney Disease (PKD) is a genetic disorder characterized by the presence of cysts or other abnormalities in multiple organs including the kidneys. People with PKD are at increased risk of developing certain health problems such as high blood pressure, heart failure, diabetes mellitus, and various types of cancer. There is no cure for PKD. Treatment options include dialysis, medications, surgery and sometimes both.
The term “polycystic” refers to the number of small sacs (glomeruli) in each kidney. Each of these small sacs is a tiny, fluid-filled compartment in the kidney that filters waste from the blood.
When cysts form, these compartments or units are replaced by sacs.
PKD is a genetic disorder. In autosomal dominant polycystic kidney disease, one copy of the defective gene is inherited from a parent and the other copy is acquired from the other parent.
In this situation, you have one chance in two (50 percent) of passing on the mutated gene to each of your children.
You may not notice symptoms of this condition until later in life. During your teens and 20s, you may experience pain in your side, especially while exercising or during menstruation.
As you age, you may be more prone to kidney cancer and kidney failure.
The condition is called Autosomal Dominant because only one copy of the altered gene is necessary for the disease to manifest itself.
Autosomal means that the mutated gene responsible for the condition is located on one of the non-gender determining chromosomes (Chromosomes 1-22). The prefix “autosomal” is derived from the Greek word autosomalias meaning “self”, which describes the fact that both men and women are equally likely to inherit the condition.
The word dominant describes the gene action or description of a single copy of a gene determining the appearance of a feature (or disease) in an individual. For example if an individual has a single copy of a mutated gene they have the disease.
The allele responsible for autosomal dominant conditions is commonly denoted with the letter “.1” and the unaffected allele is denoted with the letter “.2”.
Other examples of dominant conditions are Huntington disease, Cystic Fibrosis and Fragile X syndrome.
The word polycystic is the adjectival form of the word polycystic and means affected by or suffering from cysts.
The condition is inherited in an autosomal dominant manner. This means the disease manifests itself if a child inherits the mutated gene from either parent.
If both parents have the disease, all of their children will have the disease. The child will usually inherit the mutated gene from one of the parents.
If one parent has the disease and the other parent is unaffected, each child has a 50 percent chance of inheriting the mutated gene that causes the disease.
If you have signs of autosomal dominant polycystic kidney disease (ADPKD), you also have a higher risk of developing secondary health conditions, including:
The risk of developing high blood pressure or arterial stiffness increases as the number and size of cysts increase. Medication can help to manage high blood pressure, but the disease cannot be cured.
Eyes: Eye problems, such as glaucoma or cataracts, can lead to vision loss.
Heart: About half of people with PKD have heart-related complications. These problems can include an irregular heart rhythm known as atrial fibrillation, a narrowing of the aortic valve or an aneurysm (a weakened, enlarged area) of the heart.
Kidneys: Cysts can grow to the point where the organ is not able to work properly.
Other internal organs may also be affected, including the liver and pancreas.
How is Autosomal Dominant Polycystic Kidney Disease (ADPKD) Diagnosed?
Sources & references used in this article:
- Genotype–phenotype correlations in autosomal dominant and autosomal recessive polycystic kidney disease (S Rossetti, PC Harris – Journal of the American Society of …, 2007 – Am Soc Nephrol)
- An autosomal recessive polycystic kidney disease gene homolog is involved in intraflagellar transport in C. elegans ciliated sensory neurons (H Qin, JL Rosenbaum, MM Barr – Current Biology, 2001 – Elsevier)
- Can progression of autosomal dominant or autosomal recessive polycystic kidney disease be prevented? (ID Davis, KMR Dell, WE Sweeney… – Seminars in …, 2001 – seminarsinnephrology.org)
- Biliary dysgenesis in the PCK rat, an orthologous model of autosomal recessive polycystic kidney disease (TV Masyuk, BQ Huang, AI Masyuk, EL Ritman… – The American journal of …, 2004 – Elsevier)
- The mTOR pathway is activated in human autosomal-recessive polycystic kidney disease (JU Becker, AO Saez, K Zerres, O Witzke… – Kidney and Blood …, 2010 – karger.com)
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