Search

Background: Common hyperkeratotic palmar skin lesions include chronic hand eczema (CHE), hyperkeratotic hand eczema (HHE), palmar psoriasis (PP). However, clinically differentiating these disorders is often challenging. Objectives: To compare the expressions of keratin (K) 5, K9, K14 and involucrin in palmar hyperkeratotic lesions (HHE, CHE and PP). Materials and Methods: Immunohistochemical staining was performed on skin biopsy specimens obtained from the palms of patients clinically diagnosed with CHE, HHE and PP (n = 21, 24 and 18, respectively). Results: K5 and K14 expression levels were higher in the spinous and granular layers of PP and HHE compared to CHE. Involucrin was expressed in the basal layer of PP and HHE but not in CHE. K9 expression was decreased in PP and HHE compared to CHE. Conclusion: Keratin and involucrin expression in the epidermis are markers of keratinocyte differentiation. Expression levels of keratin and involucrin were similar between the HHE and PP groups, suggesting that HHE shares pathogenesis with PP rather than CHE. [ABSTRACT FROM AUTHOR]

Keywords: baricitinib; hand dermatitis; hand eczema; hyperkeratotic hand eczema; atopic hand eczema; JAK-inhibitor; treatment EN baricitinib hand dermatitis hand eczema hyperkeratotic hand eczema atopic hand eczema JAK-inhibitor treatment 419 421 3 04/14/22 20220501 NES 220501 Janus Kinase (JAK) inhibitors target the JAK and signal transducer and activator of transcription (STAT) signaling pathway that modulates T helper (Th)1, Th2, Th17, and Th22 signaling and is involved in many immune-mediated diseases. Hand dermatitis, hand eczema, treatment, baricitinib, hyperkeratotic hand eczema, atopic hand eczema, JAK-inhibitor. [Extracted from the article]

Keywords: dupilumab; hand dermatitis; hand eczema; hyperkeratotic hand eczema; treatment EN dupilumab hand dermatitis hand eczema hyperkeratotic hand eczema treatment 124 127 4 01/28/21 20210201 NES 210201 Dupilumab, a monoclonal antibody inhibiting interleukin (IL)-4 and IL-13 signaling, is currently approved for the treatment of atopic dermatitis (AD). Effective treatment of hand eczema with dupilumab has been reported previously in case series, two small retrospective cohorts, and one prospective observational study including atopic, irritant and vesicular hand eczema subgroups.1-4 However, the effect of dupilumab on isolated hyperkeratotic hand eczema (HHE) has not yet been described. Hand eczema guidelines based on the Danish guidelines for the diagnosis and treatment of hand eczema. [Extracted from the article]

Background: Hyperkeratotic hand eczema (HHE) is a typical clinical hand eczema subtype with a largely unknown pathophysiology. Objective: To investigate histopathology, expression of keratins (K), epidermal barrier proteins, and adhesion molecules in HHE. Methods: Palmar skin biopsies (lesional and perilesional) were obtained from seven HHE patients and two healthy controls. Moreover, 135 candidate genes associated with palmoplantar keratoderma were screened for mutations. Results: Immunofluorescence staining showed a significant reduction of K9 and K14 in lesional skin. Upregulation was found for K5, K6, K16, and K17 in lesional skin compared with perilesional and healthy palmar skin. Further, upregulation of involucrin and alternating loricrin staining, both in an extracellular staining pattern, was found. Filaggrin expression was similar in lesional, perilesional, and control skin. No monogenetic mutations were found. Conclusion: Currently, the phenotype of HHE is included in the hand eczema classification system; however, it can be argued whether this is justified. The evident expression of filaggrin and involucrin in lesional skin does not support a pathogenesis of atopic eczema. The upregulation of K6, K16, and K17 and reduction of K9 and K14 might contribute to the underlying pathogenesis. Unfortunately, comparison with hand eczema studies is not possible yet, because similar protein expression studies are lacking. [ABSTRACT FROM AUTHOR]