Prevalence of contact allergy at a dermatology clinic in China from 1990-2009.
BACKGROUND
The prevalence of contact allergy varies in different regions and populations.


OBJECTIVE
To describe the frequency of sensitization in patients with dermatitis or eczema referred to Peking University First Hospital and analyze the trends in the prevalence of common allergens from January 1, 1990, to December 31, 2009.


METHODS
A total of 1,858 patients were patch tested with the Chinese baseline series of contact allergens. Data were collected from retrospective charts and analyzed.


RESULTS
Positive reactions to one or more allergens were shown in 1,374 patients (74.0%). The most common sensitizers were nickel sulfate (25.7%), fragrance mix I (25.6%), thiuram mix (25.5%), ammoniated mercury (20.5%), and p-phenylenediamine (19.1%). A statistically significant increase of sensitization over the 20-year period was seen for nickel sulfate, fragrance mix, ammoniated mercury, colophony, ethylenediamine, and potassium dichromate. Mercapto mix showed a trend of a statistically significant decrease in sensitizations from 1990 to 2009.


CONCLUSIONS
The patterns of contact allergy in patients from Peking University Hospital are different from those of patients in other regions of China, in European countries, and in the United States. Nickel and fragrance mix were the most common allergens, and the sensitization rates of these two allergens had been increasing remarkably during the 20 years from 1990 to 2009.
Department of Dermatology, Peking University First Hospital, Beijing, China.
Xia
X
Dou
Yi
Y
Zhao
Chunya
C
Ni
Xuejun
X
Zhu
Lingling
L
Liu
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000485:Allergens / Q000009:adverse effects*; D000641:Ammonia / Q000009:adverse effects; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D017449:Dermatitis, Allergic Contact / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007509:Irritants / Q000009:adverse effects*; D008297:Male; D008627:Mercuric Chloride / Q000009:adverse effects; D008875:Middle Aged; D009532:Nickel / Q000009:adverse effects; D010328:Patch Tests; D010476:Perfume / Q000009:adverse effects; D010655:Phenylenediamines / Q000009:adverse effects; D011192:Potassium Dichromate / Q000009:adverse effects; D015995:Prevalence; D012189:Retrospective Studies; D013893:Thiram / Q000009:adverse effects; D055815:Young Adult
D000485:Allergens; D007509:Irritants; D010476:Perfume; D010655:Phenylenediamines; D013893:Thiram; C029938:nickel sulfate; D008627:Mercuric Chloride; D000641:Ammonia; D009532:Nickel; C028431:mercuric chloride, ammoniated; D011192:Potassium Dichromate; C029728:4-phenylenediamine