The hallmark of MSPI is food intolerance, not food allergy. Food allergy is an immune system response. Food intolerance is a digestive system response rather than an immune system response, for example, intolerance to lactose due to deficiency of a digestive enzyme which breaks down the lactose in milk.
The spectrum of symtpoms in MSPI could range from abdominal colic (mild symtpoms) to bloody diarrhea (severe symptoms).
Eight top allergens account for 90 percent of all food allergies. See more Allergy and Immunology mind maps here.
Milk allergy is the most common food allergy. It affects 2-3% of infants but 80-90% of affected children lose clinical reactivity to milk once they surpass 3 years of age.
30-50% of infants allergic to cow milk protein will also be allergic to soy protein. These infants should be given protein hydrolysate formula. 5% of infants with hypersensitivity to cow milk formula will also react to hydrolysate formula and will require elemental formula.
Hydrolysate formulas are enzymatically hydrolyzed and contain charcoal-treated casein or whey. Whey or "milk plasma" is the liquid remaining after milk has been curdled and strained.
Soy Protein Intolerance. eMedicine.
Milk Soy Protein Intolerance. DrGreene Content.
Allergies: Problem Foods: Is It an Allergy or Intolerance? WebMD.
Patient blog: MSPI Mama.
The Tyrolean Iceman, a 5,300-year-old Copper age individual had complete genome sequenced - he was lactose intolerant. Nature, 2012.