MEASUREMENT OF ACTINIC ERYTHEMA IN HEALTHY-SUBJECTS AND IN SUBJECTS WITH POLYMORPHOUS LIGHT ERUPTION USING A TRISTIMULUS COLORIMETER

Background: The assessment of actinic erythema using a tristimulus colorimeter has only been reported from healthy volunteers but never from subjects with photodermatosis. Objective: The aim of this study was to analyse the difference of chromometric measurements in patients with polymorphous light eruption Versus healthy subjects. Methods: Seventy-two subjects were subdivided according to two criteria: skin colour and clinical state. Measurements were done on a non-irradiated site and at the clinical minimal erythema dose site in the L*, a* and b* modes. Results: The data submitted to two-way analysis of variance demonstrate the influence of skin colour and clinical state on the above parameters. Conclusion: Chromometric measurements of L* help to differentiate skin colour, whereas those of a* enable the discrimination of healthy subjects from those with photodermatosis.