Is a genetic disorder that causes numerous cysts to grow in the kidneys. A kidney cyst is an abnormal sac filled with fluid. PKD cysts can greatly enlarge the kidneys while replacing much of their normal structure, resulting in chronic kidney disease (CKD), which causes reduced kidney function over time. CKD may lead to kidney failure, described as end-stage kidney disease or ESRD when treated with a kidney transplant or blood-filtering treatments called dialysis. The two main types of PKD are autosomal dominant PKD and autosomal recessive PKD.