No abstract

The recessive form of dystrophic epidermolysis bullosa (RDEB) is a debilitating disease caused by impairments in the junctions of the dermis and the basement membrane of the epidermis. Mutations in the COL7A1 gene induce multiple abnormalities, including chronic inflammation and profibrotic changes in the skin. However, the correlations between the specific mutations in COL7A1 and their phenotypic output remain largely unexplored. The mutations in the COL7A1 gene, described here, were found in the DEB register. Among them, two homozygous mutations and two cases of compound heterozygous mutations were identified. We created the panel of primary patient-specific RDEB fibroblast lines (FEB) and compared it with control fibroblasts from healthy donors (FHC). The set of morphological features and the contraction capacity of the cells distinguished FEB from FHC. We also report the relationships between the mutations and several phenotypic traits of the FEB. Based on the analysis of the available RNA-seq data of RDEB fibroblasts, we performed an RT-qPCR gene expression analysis of our cell lines, confirming the differential status of multiple genes while uncovering the new ones. We anticipate that our panels of cell lines will be useful not only for studying RDEB signatures but also for investigating the overall mechanisms involved in disease progression.

Background The COVID‐19 pandemic has raised questions regarding the management of chronic skin diseases, especially in patients on systemic treatments. Data concerning the use of biologics in adults with psoriasis are reassuring, but data specific to children are missing. Moreover, COVID‐19 could impact the course of psoriasis in children. Objectives The aim of this study was therefore to assess the impact of COVID‐19 on the psoriasis of children, and the severity of the infection in relation to systemic treatments. Methods We set up an international registry of paediatric psoriasis patients. Children were included if they were under 18 years of age, had a history of psoriasis, or developed it within 1 month of COVID‐19 and had COVID‐19 with or without symptoms. Results One hundred and twenty episodes of COVID‐19 in 117 children (mean age: 12.4 years) were reported. The main clinical form of psoriasis was plaque type (69.4%). Most children were without systemic treatment (54.2%); 33 (28.3%) were on biologic therapies, and 24 (20%) on non‐biologic systemic drugs. COVID‐19 was confirmed in 106 children (88.3%) and 3 children had two COVID‐19 infections each. COVID‐19 was symptomatic for 75 children (62.5%) with a mean duration of 6.5 days, significantly longer for children on non‐biologic systemic treatments ( P = 0.02) and without systemic treatment ( P = 0.006) when compared with children on biologics. The six children who required hospitalization were more frequently under non‐biologic systemic treatment when compared with the other children ( P = 0.01), and particularly under methotrexate ( P = 0.03). After COVID‐19, the psoriasis worsened in 17 cases (15.2%). Nine children (8%) developed a psoriasis in the month following COVID‐19, mainly a guttate form ( P = 0.01). Discussion Biologics appear to be safe with no increased risk of severe form of COVID‐19 in children with psoriasis. COVID‐19 was responsible for the development of psoriasis or the worsening of a known psoriasis for some children.