Polysystic Kidneys and entry?

[Shaw-13-]

One of my mates has always wanted to join the RM/Army , 3 years ago he found out after taking a blow to his kidney in rugby he has polysystic kidneys. Some members of his family have also had it.
Will this stop him from joining? After finding out about it he was advised by a few not to even try as he wont even get to selection.
Any help will be gratefully appreciated
Andy

[?Who Shot Terry Taliban?]

To be honest hes better off going too see his GP and asking, I dont know that any doctors use this site.

I dont know anything about it but I guess the risk would be if he took a blow there again?