Patients with eosinophilic disorders and patients without eosinophilic disorders to serve as normal controls

Inclusion Criteria:

• Signed informed consent obtained from the patient or parent/guardian. Assent will be obtained from all minors 11 years of age and older.
• Age 1-65 years.
• Carrying a diagnosis of eosinophilic gastrointestinal disease, eosinophilic inflammatory disease, or food allergy
• Other inclusion criteria may include: undergoing endoscopy based on evaluation by a pediatric CCHMC gastroenterologist

Exclusion Criteria:

• Recent viral infection (in preceding 1-2 weeks) such as upper respiratory tract infection, tonsillitis, or gastroenteritis. Viral infections in general may suppress or alter some cellular responses, especially lymphocyte responses in vivo.
• Oral or esophageal infections including candidiasis in the preceding 2 weeks
• Known diagnosis of another systemic or gastrointestinal inflammatory condition including, but not limited to, ulcerative colitis, Crohn's disease, indeterminate colitis, celiac disease, cystic fibrosis, or immunodeficiency.
• Concurrent use of systemic steroids, antihistamines, or other immunomodulatory drugs that may alter cellular responses.
• Concurrent use of anticoagulant medications which may alter cellular responses.