The film will not go down as the greats but certainly an interesting, enjoyable watch. The genre is definately horror but it is not overly scary. I think the film wants to be, but for me it just wasn't.
However, there is a good storyline. Boy has autoimmune problem which makes him allergic to almost everything so he has to wear a special suit. His parents find a doctor who can cure him, but he needs to stop in hospital / asylum to receive treatment. As he has the treatment, he starts seeing things.
And that is all I can say without a spoiler of any kind. The kids acting is good, helps the film along nicely. I really enjoyed this one.