Does he eat the same food pureed and not spit it out or vomit? I was wondering about a food allergy reaction or protective aversion. Like he knows it's not good for him.
Some kids with a non-IgE allergy (serious still, but not anaphylactic) have swallowing issues, failure to thrive, vomiting etc. It's called EOS - Eosinophilic (ee oh sin oh fill ick) disorders occur when the body reacts to trigger(s) by creating too many white blood cells (eosinophils) which hang out in inappropriate places creating trouble. White blood cells target germs and other invaders; in eos kids, they recognize normally harmless things as *enemies*.
Symptoms include any of the following; only ONE is necessary to justify testing. Vomiting, diarrhea, abdominal pain (which the child may not recognize - a child who grows up in pain assumes it is normal), FTT, GERD/reflux. Eos kids also frequently have eczema, asthma, and multi-food allergies (diagnosed or not - eos kids may test negative to everything).
Eos disorder is classified by where the eos hang out. So, a child may have eosinophilic esophagitis, eosinophilic colitis, etc. EE, EC, etc are all forms of EGID - eosinophilic gastrointestinal disorder.
For more info go to www.apfed.org or www.kidswithfoodallergies.org