Sensitization profiles of Malaysian and Singaporean subjects to allergens from Dermatophagoides pteronyssinus and Blomia tropicalis.
BACKGROUND
The house dust mites Dermatophagoides pteronyssinus (Der p) and Blomia tropicalis (Blo t) are the most common house dust mite species in Southeast Asia. To date, there have only been a few studies on the sensitization profile of the general populations in Southeast Asia to house dust mites. The aim of this study was to determine the profiles of Der p and Blo t sensitization among Singaporean and Malaysian subjects.


METHODS
Enzyme-linked immunosorbent assay was used to detect specific IgE to Der p and Blo t mite crude extracts as well as purified Der p 1, Der p 2 and Blo t 5 allergens. Sera used were from 229 Singaporean subjects (124 with rhinitis, 105 without rhinitis) and 143 Malaysian subjects (94 adults and 49 children with asthma).


RESULTS
The sensitization profile of rhinitis subjects to the dust mite allergens used in this study was as follows: Blo t extract positive: 91/124 (73%); Blo t 5 positive: 62/124 (50%); Der p extract positive: 61/124 (49%); Der p 1 positive: 53/124 (43%); Der p 2 positive: 45/124 (36%). The nonrhinitis subjects' sensitization profile was as follows: Blo t extract positive: 60/105 (57%); Blo t 5 positive: 24/105 (23%); Der p extract positive: 38/105 (36%); Der p 1 positive: 14/105 (13%); Der p 2 positive: 17/105 (16%). The study of Malaysian asthmatic adults showed that 39% of them were sensitized to Der p 1, 32% to Der p 2 and 37% to Blo t 5. Among the asthmatic children, sensitization to Blo t 5, Der p 1 and Der p 2 was 90, 57 and 39%, respectively.


CONCLUSIONS
This study clearly revealed that dual sensitization to B. tropicalis and D. pteronyssinus is common in the general populations of Singapore and Malaysia. Sensitization to Blo t 5 is more prevalent than to Der p 1 and Der p 2.
Yeoh
S M
SM
Department of Paediatrics, National University of Singapore, Singapore.
Kuo
I C
IC
Wang
D Y
DY
Liam
C K
CK
Sam
C K
CK
De Bruyne
J A
JA
Lee
B W
BW
Cheong
N
N
Chua
K Y
KY
D000293:Adolescent; D000328:Adult; D000368:Aged; D000485:Allergens / Q000276:immunology*; D039741:Antigens, Dermatophagoides / Q000276:immunology*; D052179:Antigens, Plant; D060829:Arthropod Proteins; D001249:Asthma / Q000276:immunology; D002648:Child; D003546:Cysteine Endopeptidases; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D008296:Malaysia; D008297:Male; D008875:Middle Aged; D012220:Rhinitis / Q000276:immunology; D012846:Singapore
D000485:Allergens; D039741:Antigens, Dermatophagoides; D052179:Antigens, Plant; D060829:Arthropod Proteins; C451163:Dermatophagoides pteronyssinus antigen p 2; C094701:allergen Blo t 5; D007073:Immunoglobulin E; D003546:Cysteine Endopeptidases; C451162:Dermatophagoides pteronyssinus antigen p 1