title: 24 and 48 h allergen exposure in patch testing. Comparative study with 11 common contact allergens and NiCl2.
abstract: Patch test reactions to 11 common contact allergens were studied after 24 h and 48 h occlusion with Finn Chambers in 390 patients. Concordant allergic results were found in 96 cases (74%). In 22 patients (17%), the reaction was positive only after 48 h and in 11 cases (8.5%) only after 24 h exposure. Most of the discordant reactions were to nickel, cobalt, neomycin, formaldehyde and perfume mix. Irritant reactions were found in 55 cases, the majority occurring after 48 h occlusion. Nickel chloride tested in parallel with 48 h exposure lead to more positive allergic and toxic reactions than nickel sulphate.
mesh_terms: D000485:Allergens / Q000633:toxicity*; D003035:Cobalt / Q000633:toxicity; D003877:Dermatitis, Contact / Q000453:epidemiology; D005557:Formaldehyde / Q000633:toxicity; D006801:Humans; D009355:Neomycin / Q000633:toxicity; D009532:Nickel / Q000633:toxicity*; D010328:Patch Tests; D010476:Perfume / Q000633:toxicity; D013997:Time Factors
chemical_list: D000485:Allergens; D010476:Perfume; D005557:Formaldehyde; D003035:Cobalt; C022838:nickel chloride; D009532:Nickel; D009355:Neomycin