My son is 17 years old before 6 months his weight...

What are the causes for morbid loss weight ?
- anemia 
- fanconi anemia 
- hyperthyrodism 
- leukemia 
- syndromatic disease 
- cancer 
- peptic ulcer 
What are the investigation?
- Cbc 
- iron profile 
- ferritin level 
- tsh 
-t3 
- t4 
- alt 
- ast 
- urea 
- creatine 
How to mange ?
- omega 3 daily one tab 
- ferroglobin daily one tab 
- indral for hyperthyrodism 
- nexium for peptic ulcer 
- and treated the above mentined causes according to the laboratory resualts