RT Book, Section A1 Dirkx, Tonja C. A1 Woodell, Tyler B. A2 Papadakis, Maxine A. A2 McPhee, Stephen J. A2 Rabow, Michael W. SR Print(0) ID 1177463013 T1 Medullary Sponge Kidney T2 Current Medical Diagnosis & Treatment 2021 YR 2021 FD 2021 PB McGraw-Hill Education PP New York, NY SN 9781260469868 LK accessmedicine.mhmedical.com/content.aspx?aid=1177463013 RD 2023/02/05 AB This disease is a relatively common and benign disorder that is present at birth and not usually diagnosed until the fourth or fifth decade. It can be caused by autosomal dominant mutations in the MCKD1 or MCKD2 genes on chromosomes 1 and 16, respectively. Kidneys have a marked irregular enlargement of the medullary and interpapillary collecting ducts. This is associated with medullary cysts that are diffuse, giving a “Swiss cheese” appearance in these regions.