[Compositae dermatitis].

BACKGROUND

Compositae dermatitis is an allergic contact dermatitis caused by plant species of the Compositae family. The first report of a cutaneous reaction to the Chrysanthemum genus was made by Howe JS in 1887. In 1895 Maiden JH reported about skin lesions among men working with Tagetes minuta. Case reports of contact allergic-ragweed dermatitis appeared in the American literature as early as 1919. The North American feverfew--Parthenium Hysterophorus was brought to India from America in 1956 and it caused thousands of cases of so-called parthenium dermatitis. Ragweed and parthenium dermatitis became prototypes for the classic, so-called "airborne" Compositae dermatitis, that affects primarily exposed skin surfaces, and produces a universal erythroderma.

BACKGROUND

The frequency of contact allergy to Compositae in Europe is higher than previously believed. It occurs most frequently in middle-aged and elderly persons, but also in all age groups. During the two past decades a more equal sex ratio has been established. The prevalence varies from 0.7-1.4% in the general population, up to 4.5% among occupationally exposed persons. Compositae allergy is among the top ten contact sensitivities in Europe. In North Europe plants were the cause of 4.4% cases of occupational allergic contact dermatitis. ETIOLOGY AND PATHOGENESIS: Among cultivated Compositae plants, Chrysanthemum is considered to be a major sensitizer in Europe (60%). Among the edible types, it is lettuce--Lactuca sativa and endive Cichorium endivia (20-30%), and wild-growing feverfew--Tanace--tum parthenium (70-90%), tansy--Tanacetum vulgare (54%), and dandelion--Taraxacum officinale (65%). Sesquiterpene lactones are the main sensitizers of the Compositae family. Other components, thiophenes and acetylenes are said to elicit only phytophotodermatitis, but recent studies have demonstrated that some thiophenes and benzofuran derivates possess not only phototoxic activity, but also sensitizing properties. Photosensitivity is present in 22-75% Compositae sensitive individuals. Extracts from Compositae are known to be phototoxic in vitro. Photoreactivity of alpha-methylene-gamma-la-ctone group of sesquiterpene-lactone directed towards the DNA base thymine, thus producing intermolecular 2 + 2 photoadducts (antigen within the cell), was also thought to be related to photosensitivity. Clinical manifestations vary from generalized eczema (20-30%), eczema of hands and face (24%), hand (36-44%), or facial eczema (11-28%). 65% of patients have vesicular hand eczema.

METHODS

Routine patch testing with sesquiterpene lactone mix, aimed testing with Compositae extracts screening mix, Compositae plants, and with their extracts, whereas the treatment of choice is a specific allergen-immunotherapy.