Time trends of contact allergy to the European baseline series in Lithuania.

BACKGROUND Monitoring trends of positive patch test reactions is useful for epidemiological surveillance and contact allergy prevention, and has not previously been reported in Lithuania. OBJECTIVES To examine and compare changes in the prevalence of contact allergy to European baseline series allergens in adults with suspected contact dermatitis during a 9-year period. METHODS In this retrospective study, patch test results of 297 consecutive patients, tested with the European baseline series in 2014-2015, were analysed and compared with the data published earlier in Lithuania. RESULTS The most common allergens were nickel sulfate (30.6%), methylisothiazolinone (MI) (13.5%), methylchloroisothiazolinone (MCI)/MI (7.4%), potassium dichromate (6.1%), cobalt chloride (6.1%), Myroxylon pereirae resin (5.4%), p-phenylenediamine (5.4%), fragrance mix I (4.7%), formaldehyde (4.4%), and methyldibromo glutaronitrile (3.7%). Increases in the prevalence of sensitization to MCI/MI (2.3% in 2006-2008 and 7.4% in 2014-2015; p < 0.0001) and nickel sulfate (16.4% in 2006-2008 and 30.6% in 2014-2015; p < 0.0001) and decreases in the prevalence of sensitization to paraben mix (3.2% in 2006-2008 and 0.3% in 2014-2015; p = 0.006) were observed. Prevalences for the other allergens remained stable or showed a decreasing trend (Myroxylon pereirae resin; p = 0.06). CONCLUSION This study provides current information on the prevalence of contact allergy in Lithuania. Changing trends in sensitivity to some allergens probably reflect changes in exposure.