Editing Autosomal dominant polycystic kidney disease (section)

==Diagnosis==
Usually, the diagnosis of ADPKD is initially performed by renal imaging using [[ultrasound]], [[CT scan]], or [[MRI]].<ref name="TP-150519-E40">{{cite journal | vauthors = Trujillano D, Bullich G, Ossowski S, Ballarín J, Torra R, Estivill X, Ars E | title = Diagnosis of autosomal dominant polycystic kidney disease using efficient PKD1 and PKD2 targeted next-generation sequencing | journal = Molecular Genetics & Genomic Medicine | volume = 2 | issue = 5 | pages = 412–421 | date = September 2014 | pmid = 25333066 | pmc = 4190876 | doi = 10.1002/mgg3.82 }}</ref> However, molecular diagnostics can be necessary in the following situations: '''''1-''''' when a definite diagnosis is required in young individuals, such as a potential living related donor in an affected family with equivocal imaging data;<ref name="TP-150519-E40" /> '''''2-''''' in patients with a negative family history of ADPKD, because of potential phenotypic overlap with several other kidney cystic diseases;<ref name="TP-150519-E40" /> '''''3-''''' in families affected by early-onset polycystic kidney disease, since in this cases [[Hypomorphic mutation|hypomorphic alleles]] and/or [[oligogenic inheritance]] can be involved;<ref name="TP-150519-E40" /><ref name="TP-150519-E41">{{cite journal | vauthors = Bergmann C, von Bothmer J, Ortiz Brüchle N, Venghaus A, Frank V, Fehrenbach H, Hampel T, Pape L, Buske A, Jonsson J, Sarioglu N, Santos A, Ferreira JC, Becker JU, Cremer R, Hoefele J, Benz MR, Weber LT, Buettner R, Zerres K | display-authors = 6 | title = Mutations in multiple PKD genes may explain early and severe polycystic kidney disease | journal = Journal of the American Society of Nephrology | volume = 22 | issue = 11 | pages = 2047–2056 | date = November 2011 | pmid = 22034641 | pmc = 3279997 | doi = 10.1681/ASN.2010101080 }}</ref> and '''''4-''''' in patients requesting [[genetic counseling]], especially in couples wishing a pre-implantation [[genetic diagnosis]].<ref name="TP-150519-E40" /><ref name="TP-150519-E42">{{cite journal | vauthors = Harris PC, Rossetti S | title = Molecular diagnostics for autosomal dominant polycystic kidney disease | journal = Nature Reviews. Nephrology | volume = 6 | issue = 4 | pages = 197–206 | date = April 2010 | pmid = 20177400 | pmc = 4050432 | doi = 10.1038/nrneph.2010.18 }}</ref>

The findings of large [[Radioopaque|echogenic]] kidneys without distinct macroscopic cysts in an infant/child at 50% risk for ADPKD are diagnostic. In the absence of a family history of ADPKD, the presence of bilateral renal enlargement and cysts, with or without the presence of [[hepatic]] cysts, and the absence of other manifestations suggestive of a different renal cystic disease provide presumptively, but not definite, evidence for the diagnosis. In some cases, intracranial aneurysms can be an associated sign of ADPKD, and screening can be recommended for patients with a family history of intracranial aneurysm.<ref name="TP-150818-01">{{cite journal | vauthors = Rozenfeld MN, Ansari SA, Shaibani A, Russell EJ, Mohan P, Hurley MC | title = Should patients with autosomal dominant polycystic kidney disease be screened for cerebral aneurysms? | journal = AJNR. American Journal of Neuroradiology | volume = 35 | issue = 1 | pages = 3–9 | date = January 2014 | pmid = 23292526 | pmc = 7966475 | doi = 10.3174/ajnr.A3437 | s2cid = 5777115 | doi-access = free }}</ref>

Molecular [[genetic testing]] by [[linkage analysis]] or direct mutation screening is clinically available; however, genetic heterogeneity is a significant complication to molecular [[genetic testing]]. Sometimes, a relatively large number of affected family members need to be tested in order to establish which one of the two possible genes is responsible within each family. The large size and complexity of ''[[PKD1]] ''and ''[[PKD2]]'' [[gene]]s, as well as marked [[allelic heterogeneity]], present obstacles to molecular testing by direct [[DNA analysis]]. The sensitivity of testing is nearly 100% for all patients with ADPKD who are age 30 years or older and for younger patients with ''PKD1'' mutations; these criteria are only 67% sensitive for patients with ''PKD2'' mutations who are younger than age 30.{{citation needed|date=June 2016}}

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Image:Adult Polycystic Kidney.jpg|Adult polycystic kidney
File:Autosomal Dominant Polycystic Kidney Disease.svg|Diagram of autosomal dominant polycystic disease with a normal kidney inset for comparison
File:CT scan autosomal dominant polycystic kidney disease.jpg|Abdominal CT scan of an adult with autosomal dominant polycystic kidney disease: Extensive cyst formation is seen over both kidneys, with a few cysts in the liver, as well. ([[Coronal plane]])
</gallery>