ABSTRACT
Although some studies have indicated that helminthic infections and house dust mite exposure may have an alleviating effect on wheeze, an interaction effect of both risk factors has not been examined in Thailand. The objective of this study was to investigate whether exposure to helminthic infections together with house dust mite allergen was associated with wheeze in children aged 18-36 months, living in an area of southern Thailand where helminthic infections are endemic. This study was undertaken as a part of The Prospective Cohort Study of Thai Children which recruited 1,076 children born between December 2000 and November 2001. A home dust sample was collected once when the infants were 12-18 months old to measure house dust mite allergen (Der p1). Questionnaire data on wheeze and a stool specimen for soil-transmitted helminth analysis were collected at age 18-36 months. Prevalence of exposure to house dust mite allergen (Der p1) > 10 μg/g dust was 31.8%. Soil-transmitted helminths were present in 25.0%, predominately Ascaris lumbricoides. Hookworm infection was asso-ciated with a physician’s diagnosis of wheeze (OR 4.20, 95% CI 1.45-12.10) and hospitalized wheeze (OR 5.40, 95% CI 1.26-23.01). Hospitalized wheeze was significantly higher in subjects exposed to Der p1 2-10 μg/g dust. Helminthic infections were not associated with a significant interaction effect with mite allergen against a risk of wheeze. Our survey confirms that hookworm infection and mite allergen exposure are independent risk factors for childhood wheeze and there is no evidence of important interaction between the two.
ABSTRACT
Several proteins of rubber latex have been recognized as allergens causing immediate hypersensitivity in humans. In this study, a bottom fraction membrane (BFM) protein preparation from Hevea brasiliensis trees grown in southern Thailand was used to detect specific IgE in four groups of serum samples. The first group included 170 samples of latex glove factory workers (LGWs); group 2 consisted of the sera of 35 health care workers (HCWs) who were repeatedly exposed to powdered latex gloves; groups 3 and 4 were 31 positive and 22 negative sera, respectively, obtained from Johns Hopkins University School of Medicine, Baltimore, USA, tested for IgE to latex allergen. It was found that 56/170 (33%), 5/35 (14%), 11/31 (35.5%) and 1/22 (4.5%) samples of the LGWs, HCWs, CAP+ and CAP- groups had significant IgE to the BFM proteins, respectively. However, of all subjects only one subject of group 1 had experienced allergic morbidity consisting of eczema, conjunctivitis and asthma. The IgE of this subject bound to a 55 kDa component in the rubber latex BFM preparation. Thus, this protein may be regarded as a novel, although minor, latex allergen. Further investigation is needed to characterize the component and to pinpoint its allergenic role.