My Younger Brother Has A Rare Genetic Disorder Called Renal

My younger brother has a rare genetic disorder called Renal Coloboma syndrome. His eye sight has always been bad but is deteriorating quickly (he got sick a year and a half ago when he fainted and was hospitalized, turned out he was in kidney failure. Before this we had no idea he was sick though I supposed technically he has been his whole life and we were all just unaware). Will he go blind? Video games are his only real coping mechanism since he got sick and I'm worried he'll lose his sight completely and not have anything left to keep him going. I've googled a lot but can't find much information on the internet about his condition.