There was a great case report recently of a 4 years old child that presented to the doctor for possible food allergies? A little of digging into the past medical history and it was discovered that the child has a normal delivery but forceps were used to progress the delivery.
Another clue: The flushing of the face only occurred on one side of the face and coincided with meals! All subsequent allergy tests were negative.
This is called: Frey’s syndrome or a.k.a. auriculo-temporal syndrome. This is a rare complication of forceps injury during delivery that is frequently misdiagnosed as food allergy in children!
As pressure is applied to the auriculo-temporal nerve by the forceps, it is damaged. This leads to regeneration of parasympathetic fibers that normally carry signals to the salivary glands to crossover with the sympathetic pathways connected to blood vessels and sweat glands. This leads to flushing and sweating at the start of a meal!
A good test is to provide a child with food. As soon as the salivary glands are stimulated, the flushing will appear. Amazing.