I first learned of Milk Soy Protein Intolerance (MSPI) in the office of a pediatric gastroenterologist's office with my seven-week-old son, Max. After the first week of his life Max lost weight and was labeled "failure to thrive." As an educated mother and nurse I was devastated that this could happen.That day in the GI specialist's office, he performed a proctosigmoidoscopy and biopsy on Max. He sat me where I could see him perform the test and told me what I would see. He said that the lining.