Age-Related Patterns in Anogenital Allergic Contact Dermatitis: A Retrospective Study

Background: Allergic contact dermatitis (ACD), can involve any area of the body. However, the anogenital region remains under-studied and diagnostically challenging. Objective: To investigate the association between age and patch test results in women presenting with symptoms suggestive of anogenital ACD. Methods: A 10-year retrospective cohort study of female patients with anogenital ACD symptoms who underwent patch testing at a tertiary medical center. Results: A total of 150 women were included and divided into two age groups: younger (<45 years, n = 86) and older (≥45 years, n = 64). Relevant positive reactions were observed in 60% ( n = 90) of cases. Older women had more frequent reactions to methyldibromoglutaronitrile (MDBGN) ( P = 0.043), hydroperoxides of limonene ( P = 0.036) and higher positivity to the medicament series ( P = 0.039). Sensitivity to Fragrance Mix I was higher among older women with isolated anogenital symptoms ( P = 0.014). Although the number of tested series was similar, older women had more positive series per patient ( P = 0.007). Conclusions: In this exploratory, hypothesis-generating study, age-related differences in allergen sensitization emerged on patch testing. Selected fragrances, preservatives, and medicament-related allergens were more frequent among women aged ≥45 years, supporting age as an important consideration in the diagnosis and management of women with suspected anogenital ACD.