4yr old. asd, gastric reflux, low iga,allergic related mediated gastrointestinal dysmotility. black bloos streaks stool. pain esophagus stomach. what?

Abdominal pain : You gave obviously been to a whole conference of physicians. You already have a huge list of legitimate GI diagnoses. If the stool is still bloody/black you need to do more. Sorry. Add these to your find out list- mechel's diverticula, h pylori, c diff, milk allergy, and endoscopy. Perhaps you need a second opinion from another doctor and hospital. Your persistence will be best solution !