PKD2 and polycystic kidney disease: Furthermore, reports indicate that approximately 40% of patients with polycystic kidneys who do not have a positive family history of polycystic kidneys do not present with PKD1 or PKD2 pathogenic variants.9, 10, 11 In patients with polycystic kidneys who have a positive family history of polycystic kidneys, ADPKD diagnosis is conducted using kidney imaging methods such as ultrasonography, computed tomography, or magnetic resonance imaging.12