Polycystic kidney disease (PKD) is an inherited disorder that affects the kidneys, as a primary site, and other secondary organs by forming clusters of fluid-filled sacs (cysts) in these organs. As cysts grow in size and number, kidneys' ability to filter blood will decrease leading to kidney failure. About half of the patients with PKD develop kidney failure by the age of 60 years. In addition, these cysts may cause pain and they may get infected. Many complications usually arise in patients with PKD including hypertension, hematuria, recurrent urinary tract infections, kidney stones, heart valve abnormalities, and aneurysm in the major blood vessels particularly the aorta. Aneurysms can be life-threatening if they rupture. However, these complications vary among patients according to the secondary affected organs which may involve the brain, intestines, ovaries, and/or any other organ. Generally, the disease is worse in men, blacks, and individuals with sickle cell disease.
PKD is divided into two main types according to the mode of inheritance and age of onset. The first type is the autosomal dominant PKD that begins in adulthood. On the other hand, autosomal recessive form of the disease is lethal and much rare, and it starts during infancy. Prevalence of autosomal dominant PKD is estimated to be 1:500 to 1:1,000 individuals. Till now, there is no active method to treat this disease, but the complications of PKD can be treated and the patient will be more comfortable.
Alterations in either PKD1 or PKD2 gene are responsible for causing the autosomal dominant form of polycystic kidney disease (PKD). Both genes encode proteins that interact with each other to enhance kidney development, organization, and function.