Helicobacter pylori infection in skin diseases: a critical appraisal.

More than 50% of the human population have long-term Helicobacter pylori infection, causing, in some cases, severe diseases such as peptic ulcers and stomach cancer. In the last few years several extra-gastrointestinal disorders have been associated with H. pylori infection. This review summarized the current medical literature, identified through hand searching and MEDLINE research, including our own studies, with regard to H. pylori and skin diseases. From the literature it can be seen that the role of H. pylori in skin diseases is still a controversial subject. Randomized controlled trials with adequate masking and sample sizes are still lacking. The best evidence comes from studies investigating chronic urticaria in which chronic urticaria disappeared in many patients with H. pylori infection after careful eradication of the H. pylori. Moreover, there are promising recent reports of beneficial H. pylori eradication in Behçet's disease, pruritus cutaneus, prurigo chronica, prurigo nodularis and in some patients with lichen planus, but not in rosacea or psoriasis. Before any conclusions with respect to other skin diseases such as atopic dermatitis, Schoenlein-Henoch Purpura, Sweet's syndrome, Sjögren syndrome or systemic sclerosis may be drawn, additional randomized, double-blinded and placebo-controlled studies including adequate diagnostic schedules, sufficient eradication treatment protocols, confirmation of eradication and adequate control groups are needed. The cutaneous pathology of H. pylori is far from being clear, but it is speculated that the systemic effects may involve increased mucosal permeability to alimentary antigens, immunomodulation, an autoimmune mechanism or the impairment of vascular integrity.