[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [General pathology](https://durgical.com/en/general-pathology/) › [Kidney](https://durgical.com/en/general-pathology/areas/kidney/) › Autosomal dominant polycystic kidney disease # Autosomal dominant polycystic kidney disease - Lesion Inherited defects in polycystin proteins make tubules swell into countless cysts that enlarge the kidneys and destroy them over decades. Updated Nov 12, 2026 ## Key points - Autosomal dominant; PKD1 on chromosome 16 (most cases), PKD2 on chromosome 4 (milder). - Both kidneys hugely enlarged, cysts up to several centimetres, filled with clear, turbid or hemorrhagic fluid. - Presents in adulthood with flank pain, hematuria, hypertension, stones and urinary infection. - Extrarenal: liver cysts (most common), berry aneurysms (subarachnoid hemorrhage), mitral valve prolapse, colonic diverticula. - Cyst growth is driven by cyclic AMP; vasopressin V2 blockade slows it. ## What it is ADPKD is one of the commonest inherited diseases and a significant cause of kidney failure. PKD1 (polycystin-1) causes most cases and more severe disease than PKD2 (polycystin-2). Polycystins in the primary cilium sense urine flow and control calcium entry; their loss raises cyclic AMP and drives cell proliferation and fluid secretion. Cysts start in all nephron segments but form in only a small fraction of nephrons, because a second somatic hit is needed in each. It has also been studied in Colombian families (see the sources). ## Structure - Kidneys may weigh several times normal; the surface is a mass of cysts, with remaining parenchyma between them. - Cysts are lined by cuboidal or flattened epithelium, sometimes papillary; some contain blood or calcified material. - Interstitial fibrosis and compression atrophy of the remaining nephrons. - The liver shows cysts derived from bile ducts; brain arteries can show saccular aneurysms. ## Step by step - Each cell carries one inherited faulty PKD1 or PKD2 allele. - In a few tubular cells, a second hit inactivates the other allele. - Without polycystin signalling, the cilium cannot sense flow and intracellular calcium falls. - Cyclic AMP rises, cells proliferate and secrete chloride and fluid into the lumen. - The segment balloons and detaches from the nephron as a closed cyst. - Thousands of enlarging cysts compress the remaining kidney and cause fibrosis and kidney failure. ## Clinical notes - Kidney failure usually develops between the fourth and sixth decades, earlier with PKD1. - Screening for intracranial aneurysms is considered for patients with a family history of hemorrhage. - Cyst hemorrhage and infection cause acute pain; stones (often uric acid) are common. ## Memory aid Two hits, one cilium, a thousand balloons. ## Test yourself Think of the answer, then tap the question to see it. ## Which gene accounts for most ADPKD and the more severe form? PKD1, which encodes polycystin-1. ## Why do cysts form in only some nephrons when every cell carries the mutation? A second, somatic hit inactivating the normal allele is needed in each cyst-forming cell. ## Which extrarenal lesion can cause sudden death in ADPKD? A ruptured berry aneurysm of the circle of Willis, giving subarachnoid hemorrhage. [Add to my cards (3)](https://durgical.app/estudiar/?add=/en/general-pathology/autosomal-dominant-polycystic-kidney-disease/) [More Pathology questions →](https://durgical.com/en/practice/?f=pathology) ## Elsewhere in DurgiPedia - [Multicystic dysplastic kidney and polycystic kidney disease](https://durgical.com/en/embryology/multicystic-dysplastic-kidney-and-polycystic-kidney-disease/) - [Mendelian inheritance: autosomal dominant, recessive and X-linked](https://durgical.com/en/general-pathology/mendelian-inheritance-autosomal-dominant-recessive-and-x-linked/) ## Connections ## Related 5 - [Cystic kidney diseases: comparison table](https://durgical.com/en/general-pathology/cystic-kidney-diseases-comparison-table/) - [Autosomal recessive polycystic kidney disease](https://durgical.com/en/general-pathology/autosomal-recessive-polycystic-kidney-disease/) - [Choledochal cysts and fibropolycystic disease](https://durgical.com/en/general-pathology/choledochal-cysts-and-fibropolycystic-disease/) - [Aneurysms: types and pathogenesis](https://durgical.com/en/general-pathology/aneurysms-types-and-pathogenesis/) - [Mendelian inheritance: autosomal dominant, recessive and X-linked](https://durgical.com/en/general-pathology/mendelian-inheritance-autosomal-dominant-recessive-and-x-linked/) ## Related conditions 6 - [Autosomal dominant polycystic kidney disease](https://durgical.com/en/conditions/autosomal-dominant-polycystic-kidney-disease/) - [Subarachnoid haemorrhage](https://durgical.com/en/conditions/subarachnoid-haemorrhage/) - [Mitral valve prolapse](https://durgical.com/en/conditions/mitral-valve-prolapse/) - [Chronic kidney disease](https://durgical.com/en/conditions/chronic-kidney-disease/) - [Kidney stones (urolithiasis)](https://durgical.com/en/conditions/kidney-stones/) - [Arterial hypertension](https://durgical.com/en/conditions/arterial-hypertension/) [← All of general pathology](https://durgical.com/en/general-pathology/) Educational content on the mechanisms of disease; not a diagnostic or treatment guide and no substitute for a health professional's advice. No doses are given. Sources: [Autosomal Dominant Polycystic Kidney Disease](https://www.ncbi.nlm.nih.gov/books/NBK532934/) (StatPearls (NCBI Bookshelf), 2024); [Autosomal dominant polycystic kidney disease in Colombia](https://europepmc.org/article/PMC/PMC10353080) (BMC nephrology, 2023). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/general-pathology/autosomal-dominant-polycystic-kidney-disease/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/general-pathology/autosomal-dominant-polycystic-kidney-disease/