A systematic literature search was conducted in PubMed, EMBASE, and Cochrane Library (January 2000–December 2024) using keywords: (“ADPKD” OR “polycystic kidney disease”) AND (“Alport syndrome” OR “COL4A5” OR “COL4A3” OR “COL4A4”) AND (“coexistence” OR “co-occurrence”). Here, COL4A5 is linked to autosomal dominant polycystic kidney disease.