The European Journal of Dermatology defines chronic urticaria (CU) as:
“A recalcitrant skin disease characterized by pruritic wheals lasting more than 6 weeks in the absence of physical cause.”
The skin wheals in chronic urticaria are raised and appear as in the image below:
The symptoms of chronic urticaria are caused by the release of histamine and other skin mediator chemicals. In other words, they are caused by an immune response.
Potential triggers include:
However in many cases, there is no known trigger, leading to a diagnosis of ‘idiopathic’ chronic urticarial.
A number of studies have indicated that H pylori infection may play a role in the development of urticaria / hives because of the damage caused to the stomach by the infection.
The inflammatory response in the stomach and small intestine (gastritis & duodenitis, respectively) that is caused by H pylori infection may lead to an increase in permeability of the delicate gut lining.
In other words, tiny gaps and holes appear in the stomach lining, which allow larger, undigested particles of food, bacterial antigens or chemicals into the blood. Once there, the immune system mounts a response, leading to inflammation on the skin.
Several other mechanisms involving the immune system may also contribute to the development of chronic urticaria in H pylori-infected people.
Some studies – I have seen the data from 16 studies in total – have shown partial or complete remission in urticaria in patients who have successfully eradicated H pylori, compared to patients who have not eradicated the infection.
Because chronic urticaria is a condition that can have a significant impact on quality of life, testing for H pylori and eradicating the infection is a worthwhile exercise.
In fact, a review paper on the role of H pylori in skin disease makes the following recommendation:
“To cure at least some patients from quality-of-life reducing chronic urticaria, it seems worthwhile to eradicate H pylori in all patients with chronic urticarial and H pylori infection.”
Other Causes of Chronic Urticaria?
Other digestive infections are reported to cause hives. Parasites such as Giardia lamblia and other microscopic bugs can certainly create an immune response that creates skin problems.
Exposure to chemicals, internally in food, air and water, as well as externally in creams, cosmetics and soaps, may also play a role in the development of urticarial/hives in some people.
Finally, it is well known that sensitivity to key foods such as gluten-containing grains and cow’s milk can cause skin problems. Whether these reactions cause urticaria is not clear.
H Pylori & Urticaria References
Magen et al. Eradication of Helicobacter Pylori Infection Equally Improves Chronic Urticaria With Positive & Negative Autologous Serum Skin Test. Helicobacter 2007; 12: 567-71.
Yadav et al. Chronic Urticaria and Helicobacter Pylori Infection. Indian J Med Sci 2008; 62: 157-62.
Federman et al. The effect of antibiotic therapy for patients infected with Helicobacter pylori who have chronic urticarial. J Am Acad Dermatol 2003; 49:861-4.
Hernando-Harder et al. Helicobacter and Dermatologic Diseases. Eur J Derm 2009; 19(5):431-44.