I'm not clear on why medical records are so sensitive. I can understand some people might want to hide HIV status - but is there anything else? In the US people have wanted to hide prior conditions from insurance companies, but I wouldn't expect this a problem in Sweden.
If you're underage you may especially want to hide those two from your parents depending on the social group. If you're a woman you may also want those two hidden from your family depending on the social group. Sweden has a large refuge population from very conservative cultures and things like acid attacks against women are decently common. So not keeping those thing hidden can get you killed or horribly injured if you're in certain social groups.