Associations Between Infectious Diseases and Urticaria

Background: Urticaria is a frequent skin disease but the majority of cases have an unknown cause (idiopathic urticaria). There is a strong association between infectious triggering factors in the pathogenesis of Acute Urticaria (AU) and infectious triggering factors may also be involved in Chronic Urticaria (CU).

Methods: We determined the prevalence of bacterial, viral and parasitic infectious diseases in 217 patients (169 females and 48 males) from North-Eastern Romania with age from 16 to 86 years, admitted in our department in the last 6 months with acute episodes of urticaria (107 females and 27 males) and chronic idiopathic urticaria (62 females and 21 males). In order to identify the infectious triggers, blood samples were used to evaluate the level of antibodies for Toxocara cannis, Toxoplasma gondii, Herpes simplex virus, Epstein–Barr virus, cytomegalovirus and measles virus. Additionaly, microscopic stool examination and fecal antigens essays for Helicobacter pylori and Giardia lambliawere performed. Serum anti-HCV antibodies and HBs antigen were assessed.

Results: The most frequent infectious agent detected in cases with AU and CU was Giardia lamblia (17.97% - 21 cases with AU and 18 cases with CU), followed by Toxocara cannis (8.29% - 11 cases with AU and 7 cases with CU), hepatitis C virus (5.99% - 8 cases with AU and 5 cases with CU), Helicobacter pylori (5.99% - 8 cases with AU and 5 cases with CU) and hepatitis B virus (1.38% - 2 cases with AU and 1 case with CU). Acute infections with Epstein–Barr virus (2 patients) and measles virus (1 patient) were diagnosed only in AU and no cases were found among patients with CU. Only 3 patients (2 with AU and 1 with CU) were diagnosed with acute infection with Herpes simplex virus. All patients had negative results for cytomegalovirus IgM antibodies. Parasitic infections with Blastocystis hominis were found in 6 patients (5 cases with AU and 1 case with CU) and one patient with CU presented Ascaris lumbricoides.

Conclusions: Infectious triggering factors, especially parasitic infections are prelevant in developing countries of the world and may play an important role not only in acute episodes of urticaria but also in chronic urticaria. Although we found that parasitic infections are present in both types of urticaria, further studies are needed to elucidate the association between infectious triggering factors and urticaria, and to identify new infectious triggers.