Clinical patterns of Compositae dermatitis in Danish monosensitized patients.

BACKGROUND: Compositae dermatitis was originally described as airborne contact dermatitis. More recent studies have reported a wider clinical spectrum, but often in polysensitized patients.

OBJECTIVE: To evaluate the clinical features of patients sensitized to Compositae only.

PATIENTS/METHODS: Consecutive Compositae-sensitive eczema patients, tested between 1990 and 2015, who, at the patch testing session diagnosing their Compositae allergy, were found to be sensitized only to the plant family, were included.

RESULTS: Altogether, 529 of 13 139 patients tested (4.0%) were sensitized to Compositae, and 95 (18% of these) were monosensitized. The majority had hand eczema, and 39 (44%) had a vesicular volar pattern. Eighty-one patients were classified into one of three groups of similar size: localized eczema, eczema of exposed skin, and localized eczema turning into widespread eczema.

CONCLUSIONS: The prevalence of Compositae sensitization is continuously high in consecutive eczema patients. Sensitization may occur at any age. Clinical features in monosensitized patients vary, but, with continuing exposure, the patients may develop more widespread dermatitis similar to classic Compositae dermatitis. Avoidance may clear the exogenous part, but not endogenous aetiological factors such as vesicular hand eczema or possible photosensitivity. Thorough clinical assessment and patient education are important in reducing the impact of Compositae contact allergy.