Polycystic Kidney Disease
What is Polycystic Kidney Disease
Autosomal-dominant polycystic kidney disease is a systemic hereditary disorder transmitted in an autosomal-dominant manner. It is genetically heterogeneous; so far, two genes have been identified. The systemic manifestations include cystic and non-cystic renal and extrarenal abnormalities. Renal cysts occur in 100% of gene carriers.
Autosomal-dominant polycystic kidney disease occurs throughout the world. The prognosis in adults is extremely variable. Progression may be slow, even after symptoms of renal insufficiency appear. However, after uremic symptoms develop, polycystic kidney disease is usually fatal within 4 years unless the patient receives treatment with dialysis, a kidney transplant, or both. The prevalence in reported series varies between 1 in 400 and 1 in 1,000 in people of European descent. The age- and sex-adjusted yearly incidence rate in the United States is 1.38 in 100,000. This figure almost doubles if those people in whom the diagnosis was made at autopsy are included.
Overall, approximately 600,000 Americans have the disease, making Autosomal-dominant polycystic kidney disease one of the most common hereditary disorders in the United States. Although both types of polycystic kidney disease are genetically transmitted, the incidence in two distinct age groups and different inheritance patterns suggest two unrelated disorders. The infantile type appears to be inherited as an autosomal recessive trait; the adult type, as an autosomal dominant trait. Both types affect males and females equally. The frequency of the disease in people of non-European ethnic background is not known; it may be less frequent in blacks.
Autosomal-dominant polycystic kidney disease is an important cause of ESRD; it accounts for approximately 4% of ESRD in the United States and 8% to 10% in Europe and Australia. Polycystic kidney disease can’t be cured. The primary goal of treatment is preserving renal parenchyma and preventing infectious complications. Management of secondary hypertension will also help prevent rapid deterioration in function. Progressive renal failure requires treatment similar to that for other types of renal disease, including dialysis or, rarely, a kidney transplant. In Japan, approximately 5% of patients with ESRD have Autosomal-dominant polycystic kidney disease.