My son please help!

My son now has 6 months throwing up blood & acid.." now it is mostly acid. he is on a PICC line 12hrs a day, but GI & immune doctors dont know what it is. At first they thought it might be what I have, which is Celiac, but no, then they thought he might have Chrones, but after treatment, that was also ruled out. he had the endoscopy, colonscopy, bone marrow, the camera pills for the middle part of stomach, the X-Rays, ultrasounds, the CAT-scans, and now my son hardly wants to eat. he is only 16 and has been tortured by these test above on repetitive times. he had h-pyloria, tubercolisis, and pnemonia (pneumonia), and was treated for all, but his stomach is still not able to retain food. Please help! what can i do???