[Study on the contact allergen in 720 patients with dermatitis and eczema].

In order to investigate the causative factors of dermatitis and eczema, patch test was performed using the GB7804-87 standard allergens in 720 patients with dermatitis and eczema. There were 376 patients reacted to one or more allergens. The total positive reaction rate was 52.2%. Positive reactions were most frequently with cobaltsulphate (118 cases, 16.4%), potassium dichromate (115 cases, 16.0%), nickelchloride (108 cases, 15.0%) mercuric chloride (106 cases, 14.7%), Beihai detergent powder (63 cases, 8.8%), and p-phenylene diamine (50 cases, 6.9%). The positive rate was above 1% in 18 allergens. This study shows that the standard screening allergens are valuable in the investigation of the aetiology of the dermatitis and eczema.