Fruktosemalabsorption - Eine unterschätzte form der nahrungsmittelunverträglichkeit

Background: Fructose malabsorption represents an increasing problem in clinical medicine. Its prevalence, diagnosed by a positive H ₂ exhalation test, is estimated to be between 35-60% in Europe, half of the patients being symptomatic. A disturbed fructose transport in the gastrointestinal tract is believed to be the cause of this carbohydrate malabsorption. Complex gastrointestinal symptoms like nausea, diarrhea, or cramping may mimic chronic inflammatory bowel diseases or food allergies. Methods: 20 patients suspected to suffer from adverse food reactions and with symptoms like nausea, diarrhea, and cramping were examined allergologically and gastroenterologically. Results: Eleven (55%) of the patients showed a fructose malabsorption and four (20%) had lactose intolerance, as diagnosed by hydrogen exhalation testing. By placebo-controlled oral provocation tests, adverse reactions to food additives, salicylic acid, and biogenic amines were detected in four patients. Three patients suffered from oral allergy syndrome. Systemic mastocytosis as cause of gastrointestinal symptoms was diagnosed in one patient. Conclusion: Fructose malabsorption may be underestimated and its diagnosis should be considered in the differential diagnosis of adverse food reactions.