Nutritional Deficiencies and Food Allergy

Signs and symptoms might include growth restriction, pallor/anemia (Fe and B vitamin deficiency), dermatitis (zinc deficiency), osteopenia (calcium and/or vitamin D-dependent nutritional rickets), developmental delays or regressions, feeding aversion, and nonspecific gastrointestinal symptoms. Laboratory testing in suspected cases can include measurements of total protein and albumin, calcium, hemoglobin/hematocrit, iron studies, hepatic function tests, specific nutrient levels (such as zinc, B vitamins, and fat-soluble vitamins including vitamin D), and studies for other comorbid conditions (stool studies for protein-losing enteropathy; endoscopic evaluation for eosinophilic gastrointestinal disorder).