RESUMO
BACKGROUND: Latex allergy is a major occupational health problem in health care workers who regularly use latex gloves. Dentists are one of the high risk groups for latex allergy and sensitization as it is generally found that healthcare workers (HCW) have 3 times greater prevalence of latex allergy. There are very few studies of latex allergy in HCW in Thailand. OBJECTIVE: To study the prevalence of latex-related symptoms, latex-sensitization and possible risk factors in dental students. MATERIAL AND METHOD: A cross-sectional study was performed on all dental students of the Faculty of Dentistry, Chulalongkorn University, during Dec 2007 to May 2008, using questionnaires and skin prick tests (SPT), using 3 latex extracts prepared from Proglove, Doctor Plus gloves and a commercial latex allergen (Stallergenes, France). SPT was done only in those who were willing and signed informed consents. RESULTS: There were 617 completed questionnaires (87.3%). The mean age of the volunteers was 20.9 +/- 1.7 years with 29.3% male and 70.7% female. The prevalence of latex glove-related symptoms was 5.0%. These symptoms were all local, cutaneous symptoms, ranging from hand pruritus (64.5%), hand eczema (19.4%) and contact urticaria (16.1%). Eight subjects (1.3%) reported pruritus or urticaria on exposure to other rubber products while 12 subjects (1.9%) reported reactions to some fruits. The risk factors for latex-glove allergy were personal history of allergic diseases (atopic dermatitis, urticaria, pruritus and rubber allergy), duration of using gloves more than 18 hours per week, more than 3 pairs of gloves used per day and timing of glove exposure. The 4th to 6th year students were observed significantly more prevalence of symptoms than the 1st to 3rd year students (OR, 3.69; 95% CI, 1.73-7.87; p = 0.0003). SPT for 3 extracts of latex was done in 247 cases (40.0%); overall latex sensitization rate was 14.2%. The commercial extract had higher incidence of latex sensitization compared to the 2 gloves extract. The 1st year students had the lowest percentage of latex sensitization (3.2%) and positive skin test was significantly found in the 2nd year students (20.8%; OR, 6.46; 95% CI, 1.87-47.98; p = 0.04). CONCLUSION: The prevalence of latex allergy in dental students is 5% and the signs and symptoms were local cutaneous reaction; pruritus, eczema and contact urticaria. The latex sensitization rate in dental students was14.2%, which is higher than the general population. The possible risk factors included personal history of allergic diseases, duration and frequency of exposure. Therefore, primary prevention of the occupational latex allergy should be carefully considered especially concerning high risk factors.
