title: The role of focal infections in the pathogenesis of psoriasis and chronic urticaria.
abstract: BACKGROUND
  The Focal Infection Theory, originally presented at the beginning of the 20(th) century, postulates that systemic diseases can be caused by microorganisms that arise from the focus of infection. Foci of infections have been described as sinuses, adenoids, tonsils, teeth, genitourinary tract, gall bladder and kidneys. A focus of infection is defined as the area that can occur in any part of the body, contains a pathogen (microorganism) and is usually asymptomatic. There are discordant opinions about the role of focal infections in the pathogenesis of psoriasis and urticaria.
  
  
  OBJECTIVE
  To establish whether there is a higher incidence of focal infections in patients with chronic urticaria and psoriasis.
  
  
  METHODS
  We retrospectively reviewed 129 patients with a history of psoriasis and chronic urticaria: 58 women and 71 men treated in the Department of Dermatology of the Jagiellonian University Medical College in Krakow.
  
  
  RESULTS
  In the analyzed group, 11 patients had a dental consultation, 58 - laryngological consultation and 29 women had a gynecological consultation. The most common examples of focal infection were tonsillitis, upper respiratory tract infections, sinusitis, dental caries and genitourinary tract infections. Aggravating factors were similar to previously described.
  
  
  CONCLUSIONS
  A high incidence of focal infections in patients with psoriasis and urticaria suggests that infections may play a significant role in the pathogenesis of these skin disorders. Treatment of infection foci may play the key role in the remission of skin changes.
authors.affiliation: Department of Dermatology, Jagiellonian University Medical College, Krakow, Poland. Head: Prof. Anna Wojas-Pelc MD, PhD.
authors.forename: Paweł Łukasz
authors.initials: PŁ
authors.lastname: Brzewski
authors.forename: Magdalena
authors.initials: M
authors.lastname: Spałkowska
authors.forename: Magdalena
authors.initials: M
authors.lastname: Podbielska
authors.forename: Joanna
authors.initials: J
authors.lastname: Chmielewska
authors.forename: Marta
authors.initials: M
authors.lastname: Wołek
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Malec
authors.forename: Anna
authors.initials: A
authors.lastname: Wojas-Pelc
keywords: focal infection; psoriasis; urticaria