The association between
urticaria and
infectious diseases has been discussed for >100 years. However, a causal relationship with underlying or precipitating
infection is difficult to establish. The purpose of this work was to perform a systematic analysis of the published cases of
urticaria associated with
bacterial infections. We give an umbrella breakdown of up-to-date systematic reviews and other important publications on the complex association of
urticaria and
bacterial infections. We did a Medline search, for English language articles published until January 2014, using the key words "
urticaria" and "bacteria/
bacterial disease"; a second analysis was performed in groups of bacteria and using each germ name as a key word. Many
bacterial infections have been associated with
urticaria manifestation, such as Helicobacter pylori, Streptococcus, Staphylococcus,
Mycoplasma pneumonia, Salmonella, Brucella, Mycobacterium leprae, Borrelia, Chlamydia
pneumonia, and Yersinia enterocolitica. In some cases the
skin manifestations, described as
urticaria, could be caused by the presence of the microorganism in the skin, or for the action of their toxins, or to the complement activation mediated by circulating
immune complexes. Although only a weak association with
urticaria of unclear pathogenesis exists, clinicians should consider these bacterial agents in the workup of the patients with
urticaria. The eradication of the
infection could, in fact, lead to the resolution of
urticaria. Prospective studies and well-structured research are obviously needed to better clarify the real role of bacteria in the pathogenesis of
urticaria and their relative prevalence.