Dietary Allergy/intolerance

Introduction

“Adverse reaction to food” or “dietary sensitivity” are broad terms that imply a physiological reaction or clinical sign caused by an abnormal response or reaction to an ingested substance. The sign may reflect either an immunologic response (true allergy) or a chemical or toxic reaction (intolerance) (Table 1). In the vast majority of cases the clinician is unable to differentiate the etiology and hence adverse reaction to food is the preferred term, notwithstanding the common usage of the terms food allergy or food hypersensitivity. [...] 

Key Points

• Dietary allergy and intolerance are manifested by the same clinical signs
• Diagnosis is by an exclusion-challenge-rescue protocol
• Diagnosis by serology is unreliable
• Treatment is by a carefully selected exclusion diet or a hydrolyzed diet