Prevalence of Contact Sensitization in Patients with Atopic Dermatitis: A Retrospective Study from China

The prevalence of contact sensitization in atopic dermatitis (AD) has been controversial and remains poorly studied in the Chinese population. This retrospective study aimed to assess the prevalence and differences ofin contact sensitization between AD and non-AD patients undergoing patch testing in China. We analyzedanalysed clinical records of 3,487 patients who underwent patch testing from 2018 to 2023,, including 146 AD patients and 33413,341 non-AD patients. Results demonstrated that contact sensitization prevalence was similar in AD and non-AD groups (82.88% vs 84.71%, p=0.55). Common allergens included nickel, methylisothiazolinone, dodecyl gallate, and cobalt chloride hexahydrate in both groups. AD patients showed higher positive reactions to hexahydro-1,3,5-tris-(2-hydroxyethyl) triazine (11.11% vs 5.85%, p<0.01), methyldibromo glutaronitrile (10.27% vs 4.97%, p<0.01), quaternium-15 (7.53% vs 3.68%, p=0.02), ethylenediamine dihydrochloride (3.42% vs 0.72%, p<0.01), propylene glycol (2.86% vs 0.60%, p=0.01), and 2-bromo-2-nitropropane-1,3-diol (2.74% vs 0.78%, p=0.03), compared to non-AD, particularly females. Contact sensitization prevalence increased with age in both groups. This study showed that the prevalence of contact sensitization was comparable between the AD and non-AD groups in China. However, AD patients exhibited heightened sensitivity to formaldehyde releasers and propylene glycol, commonly found in moisturizers.