Evaluation of Formaldehyde Allergy in a Patch-test Population
摘要
Formaldehyde (FA) in industrial, cosmetics and house-hold products is of importance for the induction of allergic contact dermatitis. Among 3,403 patients(1,006 men, 2,397 women) consecutive- ly patch tested at National Taiwan University Hospital in the past 23 years, 128 patients (23 men, 105 women) showed a positive reaction to FA. The overall prevalence rate of FA sensitivity was 3.8%. The women patch-tested presented with eczema primarily involving the head and neck region, followed by the hands and arms, whereas the men more frequently presented as a hand dermatitis. Among them 19.5%(25 women) were suspected due to cosmetics; 24 women presented with a facial dermatitis and, 1 presented with a dermatitis on the scalp. 18%(10 women and 13 men) of the studied population diag- nosed an occupational dermatitis, 87%(20 patients) had a dermatitis involving at least the hands. Often the sources of FA sensitivity are occult. Further patch testing with preservative series or industrial biocide tray, as well as chemical analysis for the identification of FA using chromotropic acid method in the cosmetics, hair preparations and chemical products in contact with the patients may facilitate in identifying the source of allergen.