Table of Content


Winter 2013, Vol. 21 No. 4

Hong Kong J. Dermatol. Venereol. (2013) 21, 171-180

Original Article

Patch testing: clinical relevance and successful recall of allergens in local Chinese patients


CFY Siu 蕭鳳兒 and TS Cheng 鄭天錫


Objectives: To investigate the clinical relevance of contact allergens identified in patch testing, and the successful recall rate of these allergens. Methods: This was a single-centre study performed in Hong Kong. Local Chinese patients were invited for interviews. Results: There were a total of 146 patients with valid patch tests performed from 2009 to 2012. One hundred patients were interviewed, of which 68 patients had positive patch test reactions, resulting in a total of 122 allergen reactions. Nickel sulphate, fragrance mix, 5-chloro-2-methyl-4-isothiazolin-3-one+2-methyl-4-isothiazolin-3-one (3:1 in water) and paraphenylenediamine (PPD) were the commonest allergens identified in this study. Among these sixty-eight patients, 80.3% of the identified allergens were clinically relevant (45.9% definitely relevant, 34.4% probably or possibly relevant). 75.4% of the allergens were successfully recalled, either in their full names or substance groups. Patients with a lower education level were less likely to recall the allergens identified in patch testing. Conclusion: The clinical relevance of allergens and the recall rate were satisfactorily high.


Keywords: Patch test, allergic contact dermatitis, clinical relevance, recall

關鍵詞: 關鍵詞:斑貼試驗,過敏性接觸性皮炎,臨床相關性,憶述