[Hand eczema or psoriasis: update on the FB 323 study occupational dermatology cohort].

In daily dermatological practice, the distinction between eczema and psoriasis in dermatoses of the hands can be difficult. However, a clear diagnosis is necessary to initiate optimal therapy and management. In recent years, the so-called molecular classifier has been developed for optimized differentiation of eczema and psoriasis. An occupational dermatological cohort has been established at Heidelberg University Hospital since 2020. It is funded by the German Statutory Accident Insurance. The aim is to follow-up patients over 3 years where this new diagnostic method is used and to compare the results with a retrospective occupational dermatological cohort. Recruitment ended in December 2022. The current analysis reports participants' occupational activity, insurance status, disease progression, and number of sick days. A total of 287 patients were included; mean age was 50.4 years and 63.5% (n = 181) were undergoing treatment at the expense of the liable statutory accident insurance at the start of the study. About 50% of the patients worked in health professions, metal industry, or construction. The average duration of occupational dermatosis was 6.5 years. In 38.9% of the patients, the clinical diagnosis had been classified as unclear by the treating dermatologist. By using the molecular classifier, the diagnosis could be clarified in 98% of the cases (eczema vs. psoriasis). The first analyses demonstrate that the molecular classifier contributes to improving therapy by optimizing the diagnosis.