Irritant reactivity is a better risk marker for nickel sensitization than atopy.

In order to optimize patch test strategies and counselling in occupational dermatology, it is important to identify risk markers of contact sensitization. Since nickel is the most frequent contact allergen in European countries, we studied the potential of the irritant response to sodium lauryl sulfate (SLS) to predict nickel sensitization. In 100 patients subsequently tested in our patch test clinic with the standard patch test series of the German Contact Dermatitis Group (DKG), the atopy score as described by Diepgen et al. was determined and an SLS patch test was performed. Relative transepidermal water loss (TEWL), expressed as the ratio between the TEWL of the SLS-irritated and the control site, atopy score, age and sex were tested by logistic regression analysis for their association with patch test-proven nickel sensitization. Age, sex and relative TEWL were found to be significant predictors of nickel sensitization, whereas the atopy score was not. Patients with nickel sensitization were significantly younger (mean age 35.0 +/- 4.1 versus 46.2 +/- 2.1 years), more frequently of female gender (28.6% versus 3.9%) and had a significantly higher relative TEWL following SLS exposure (471.0 +/- 40.8% versus 344.0 +/- 16.2%). The mean atopy score of nickel-sensitized patients was slightly higher than that of patients not sensitized (6.0 +/- 1.3 versus 5.3 +/- 0.5), but the difference was not significant. In previous studies on larger patient samples, atopy was found to be a predictor of nickel allergy. This discrepancy may be explained by the smaller statistical power of our study.(ABSTRACT TRUNCATED AT 250 WORDS)