COL4A4 and X-linked hydrocephalus with stenosis of the aqueduct of Sylvius: A systematic review of 777 thin basement membrane nephropathy/ADAS patients with a single mutation (COL4A3/COL4A4) showed that the prevalence of ESRD in this population was 15.1%, compared to a prevalence of 62% in patients with ARAS and 70% in male patients with XLAS.