Vava, Think what you want, but when I said 'exposed to cold' I mean after I play a sport in cold weather, and am drenched in sweat, instead of getting changed immediatelly I bum around for an hour, body tempreture drops, the sweat on the shirt cools, and the pain starts, but I know better now. Might be something genetic, coz my grandfather died of kidney failure when my father was only 3.....