Related Experiment Video
Updated: Aug 4, 2026

Recognition of Epidermal Transglutaminase by IgA and Tissue Transglutaminase 2 Antibodies in a Rare Case of Rhesus Dermatitis
Published on: December 15, 2011
Pseudoallergic reactions in chronic urticaria are associated with altered gastroduodenal permeability
1Department of Gastroenterology, Hepatology, and Endocrinology, Charité Universitätsmedizin Berlin, Berlin, Germany.
Background:
In a subgroup of patients with chronic urticaria (CU) the disease is caused by pseudoallergic reactions to food. The aim of this study was to investigate whether disturbances of the gastrointestinal barrier function play a role in the pathomechanism of the disease.
Methods:
In 55 patients with CU gastrointestinal permeability was measured with an in vivo triple-sugar-test before and after 24 days of a diet low in pseudoallergens. Sucrose served as marker for gastroduodenal permeability, lactulose/mannitol ratio for intestinal permeability.
Results:
Basal gastroduodenal and intestinal permeability were significantly higher in patients with urticaria as compared to controls. In 29 of the 55 patients skin symptoms decreased or completely disappeared during the diet (responders). Compared to nonresponders (n = 26), responders had a significantly higher gastroduodenal permeability before treatment (0.36 +/- 0.04 vs 0.15 +/- 0.01% sucrose; P < 0.001), which decreased after the diet (0.17 +/- 0.02; P < 0.001). The number of patients with Helicobacter pylori infections did not differ between the two groups.
Conclusions:
The results indicate that in a subgroup of patients with CU and pseudoallergy an impaired gastroduodenal barrier function may be of pathophysiological importance. The underlying mechanisms seem to be independent of H. pylori infection.
Related Concept Videos
Allergic Reactions
Allergic Drug Reactions
Gastritis-II: Pathophysiology
In acute gastritis, the gastric mucosa becomes swollen and red and undergoes superficial erosion. Superficial ulceration may lead to bleeding.
In chronic gastritis, persistent or repeated insults lead to chronic inflammatory changes and, eventually, thinning or atrophy of the gastric tissue.
Gastritis can stem from various causes, each...
Peptic Ulcer Disease I: Introduction
An acute ulcer, marked by superficial erosion and minimal inflammation, swiftly resolves upon identifying and addressing the underlying cause. In contrast, a chronic ulcer persists, potentially eroding through the muscular wall and forming fibrous tissue.
Peptic ulcers can also be...
Drug Toxicity: Allergic Reactions
Allergic Reactions: Anaphylaxis

