Contact sensitization in Chinese patients with hand eczema

Contact sensitization is an important cause of hand eczema, a common disease that affects both daily and occupational life.

To describe contact allergens in Chinese patients with hand eczema and to analyze the association between allergens and occupational exposure.

Three hundred sixty-six patients with hand eczema underwent patch testing with a modified North American standard series between September 1989 and December 2009.

Positive patch-test reactions were observed in 74% of patients. The most frequent allergens were p-phenylenediamine (22.7%), nickel sulfate (21.9%), fragrance mix (19.9%), ammoniated mercury (19.7%), and carba mix (17.8%). Nickel and fragrance allergy in women, and carba mix and chromate allergy in men, showed gender predilection, and 64.2% of patients developed hand eczema from occupational exposure. Positive reactions to p-phenylenediamine in hairdressers and to chromate in metalworkers and construction workers presented higher frequencies (p < .05).

p-Phenylenediamine, nickel, fragrance, mercury, and rubber chemicals are common allergens in Chinese patients with hand eczema. Gender and occupation may cause different exposures; thus, allergens may vary.