The study explores the immune landscape of chronic hand eczema using spatial transcriptomics and single-cell proteomics, offering new insights into disease mechanisms and potential therapeutic targets.

Patients aged 18 to 65 affected with chronic hand eczema will be included in the study. As clinical practice, severity of chronic hand eczema will be evaluated by validated scores as HECSI, DLQI, and NRS itch. Moreover patch tests will be performed. Skin biopsies will also be performed to confirm the diagnosis.

This study utilizes spatial transcriptomics and single-cell spatial proteomics to analyze biopsies of chronic hand eczema. It aims to identify distinct inflammatory cell subgroups and molecular markers that define the immune landscape of chronic hand eczema.

By comparing endogenous (atopic dermatitis, dyshidrotic eczema, idiopathic forms) and exogenous (allergic/irritant) chronic hand eczema, the research wants to describe specific immune endotypes and potential therapeutic targets.

The study also includes idiopathic chronic hand eczema subtypes, such as pompholyx and hyperkeratotic eczema, to clarify immune profiling and improve treatment strategies. By identifying molecular signatures unique to each chronic hand eczema subtype, this research could lead to more personalized and effective therapies.

Inclusion Criteria:

• Patients affected with chronic hand eczema of endogenous and/or exogenous origin, age from 18 to 65 years
• Patients affected with eczema located on the hands for at least 3 months or with ≥ 2 disease flare-ups in the last year.
• Patients affected with atopic dermatitis affecting the hands and other areas of the body, provided the eczema lesions involve less than 30% of the body surface area.

Exclusion Criteria:

• Concurrent or previous treatment with immunosuppressants, except for short courses of systemic corticosteroids (less than one month of continuous treatment), or biologic agents that may affect the clinical aspects or progression of chronic hand eczema.
• Patients who have received systemic corticosteroids within one month prior to enrollment in the study.
• Patients using topical corticosteroids or calcineurin inhibitors within one week of study enrollment (this time frame is considered to provide a good balance between potential residual pharmacological effects and ethical considerations).
• Patients with chronic hand eczema of mixed etiology (e.g., allergic and atopic) or those considered "etiologically unclassifiable" will not be included in the data analysis.

comphrensive spatial transcriptomic on skin biopsies of chronic hand eczema aims to describe differerent immune endotypes