What is a diseases/disorders that meet this criteria? (for a novel in progress)?

I'm writing a story, and to fulfil the plot, three characters need to enter the hospital. I have decided how two of the characteres will enter , but I'm unsure how the last should enter.

It is for a boy (Yan) aged somewhere between 19-21. Throughout the story he will appear to be fine (until he can't hide it anymore), but he know's he isn't well. He will visit the hospital frequently, but will live at home. His mother also died of an unmentioned condition (so, the boy's condition could but doesn't have to be genetic).

The boy will be unter intense stress as a result of raising his younger brother, dealing with his father's past actions against Yan's mother (alcoholism, adultry, and divorce), working throughout the day, continuing college courses through correspondance at night, and finding a way to keep his mother's house (and other financial issues). So, the disease can be a result of or intensified by his stress' affect on his immune system.

This disease or the effects thereof will ultimately result in this characters death in the course of 1-2 years, but its effects should still be subtle because he must still live at home.

How about Crohn's disease? It is an auto immune, gets worse with stress and people can die from it. You can contract Crohn's at any age.

Give him leukemia or lymphoma.

Check out MS. It's usually a disease which comes on toward middle age but is now, with increasing frequency, showing up in younger people. For more info about it go to...

Well, I have Lupus and thats an autoimmune disease that can be triggered by stress. Its seen in more woman than men, but men do get it.

Untreated Celiac Disease can be silent and deadly. The symptoms vary for every person and stress triggers it as well as genetic markers for it. He would have typical stomach issues but would probably have them blown off my docs or he'd ignore them. Finally he'd get so sick it might be too late and he'd die of malnutrition. (Not likely but does indeed happen) More commonly, untreated Celiac leads to cancers that kill.
www.celiac.com
www.celiac.org
www.csaceliacs.org

Just be sure to do your research on whatever disease you pick bc u need your facts to be straight.

You have a few options if you want it to affect his immune system, but dont want him to neccisarily look ill. first there is lupus, which can attack any organ, even the brain, left untreated, and if it goes to kidneys,heart, lungs, even liver, can kill you within 2-3 years. than there is a less commen autoimmune disorder which is more complicated, and can tun into many disease, Mixed connective tissue disease or MCTD for short, it can attack any organ, turn into scleradoma, which leads to hardening of skin and interanl organs, no treatment again 2-3 yrs if severe death. or in rare cases MCTD can turn into rare forms of Mytosis, Muscular Dystrophy (he would loose muscle control (but have a 3 -5 yr lfe span, if hits heart or lungs). Those are the main self made autoimmune disorders where you seem healthy for quite awhile, until your really under attack. by then the results are noticable, and it would likely be too late for treatment, escpecially in the case of Lupus nerphritis, where kidneys get attacked, and it is highly prevelant in asians.

dementia, stress can lead to a stroke, and then lead to some sort of viral demential from a weakened immune system, which ultimately consume his mental state and consume his life eventually because hes unable to take care of himself and die from malnutrition....heheeh...can i be a cowriter.

How about an unusual condition ? Fanconi Anemia is one that would require a bone marrow transplant sooner or later but can be maintained/treated with weekly or bi-weekly infusions of blood and or platelets. This would keep him secretly going to the hospitals for infusions and to keep his health up while he is doing everything else.

how about depression? that sounds like it would fit your story. Depression affects every aspect of your life, including your general medical health and if left untreated can cause death in many different ways. And if the person suffering from depression is really good they can hide their problem for years.