Contact and photocontact sensitization in chronic actinic dermatitis: a changing picture.

BACKGROUND

Patients with chronic actinic dermatitis (CAD) frequently have positive patch or photopatch tests. In our previous study (period 1987-1992), the most prominent contact allergen was the sesquiterpene lactone mix (36% of patients with CAD).

OBJECTIVE

To assess whether contact allergy profiles in CAD patients between 2000 and 2005 have changed in respect to our previous data (1987-1992).

PATIENTS AND METHODS

Fifty CAD patient records from 2000 to 2005 for patch and photopatch testing were retrospectively analysed and data were compared with that from 86 patients seen between 1987 and 1992.

RESULTS

Thirty-two (64%) and 64 (74%) patients had positive patch or photopatch tests in 2000-2005 and 1987-1992, respectively. The allergen profile has altered. A decline in sesquiterpene lactone mix positive reactions was noted: 29 (36%) patients were positive in 1987-1992 and 10 (20%) patients in 2000-2005, but this was not significant (P = 0.08). Reactions to non-fragrance consumer allergens (i.e. p-phenylenediamine and preservatives) had risen from 7 reactions (1987-1992) to 21 reactions in 13 individuals (2000-2005) (P < 0.001). Of these allergens, p-phenylenediamine was the most common (12%; P = 0.004).

CONCLUSIONS

A significant rise in positive patch tests to non-fragrance consumer allergens, particularly p-phenylenediamine, was seen in CAD patients in 2000-2005. We speculate this alteration of allergen profile may be partly due to changes in exposure patterns.