title: Allergic contact reactions in the skin assessed by electrical impedance - a pilot study.
abstract: OBJECTIVE
  In our previous studies of the electrical impedance of the skin, we formulated a set of physical indices that could be used to distinguish between the cutaneous effects produced by different chemical irritants. We now describe an investigation of allergic contact reactions, using the same set of impedance indices for characterization.
  
  
  METHODS
  Skin reactions were induced in the forearm of eight female patients who were allergic to nickel by exposure to nickel sulphate in petrolatum at various concentrations. The responses were evaluated by measurements of electrical impedance and transepidermal water loss, as well as by visual scoring and biopsy. Normal skin was used for controls.
  
  
  RESULTS
  Different degrees of allergic contact reactions were produced, and the changes in value of the impedance indices were found to follow a particular pattern. This pattern diverged markedly from that obtained in controls, and the differences were statistically significant.
  
  
  CONCLUSIONS
  Our results suggest that, by the application of a technique based on electrical impedance, it will be possible to characterize allergic skin reactions.
authors.affiliation: 1Department of Dermatology, Huddinge University Hospital2Center for Oral Biology, Karolinska Institute, NOVUM3Department of Pathology, Huddinge University Hospital, Huddinge, Sweden.
authors.forename: I
authors.initials: I
authors.lastname: Nicander
authors.affiliation: 1Department of Dermatology, Huddinge University Hospital2Center for Oral Biology, Karolinska Institute, NOVUM3Department of Pathology, Huddinge University Hospital, Huddinge, Sweden.
authors.forename: S
authors.initials: S
authors.lastname: Ollmar
authors.affiliation: 1Department of Dermatology, Huddinge University Hospital2Center for Oral Biology, Karolinska Institute, NOVUM3Department of Pathology, Huddinge University Hospital, Huddinge, Sweden.
authors.forename: B L
authors.initials: BL
authors.lastname: Rozell
authors.affiliation: 1Department of Dermatology, Huddinge University Hospital2Center for Oral Biology, Karolinska Institute, NOVUM3Department of Pathology, Huddinge University Hospital, Huddinge, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Emtestam
keywords: allergic; electrical impedance; nickel sulphate -non-invasive