Programme Hospitalier Recherche Clinique, Institut Pasteur, Inserm, French Public Health Agency.

4 On behalf of the SNDV (syndicat national des dermatologues-vénéréologues)/Corona group 5 President of the SNDV (syndicat national des dermatologues-vénéréologues)

Background: Dupilumab is the first biologic available to treat atopic dermatitis (AD). Its effectiveness and safety were demonstrated in clinical trials. Objective:We sought to assess the effectiveness and safety of dupilumab in adults with AD in a real-life French multicenter retrospective cohort.Methods: Patients were included between March 2017 and April 2018. Efficacy outcomes were collected both at baseline and three months (M3), when available, including SCORAD (Scoring Atopic Dermatitis) and EASI (Eczema Area and Severity Index) scores. Adverse events (AE) were recorded at the follow-up. Results:We included 241 patients. The median follow-up time was 3.8±3.7 months. SCORAD75 and EASI75 were achieved in 27/163 (16.6%) and 40/82 (48.8%) patients, respectively. The median SCORAD and EASI at M3 were significantly lower compared with baseline (25±21 vs 56±27.4, p<10 -9 and 4.1±6.8 vs 17.9±15.4, p<10 -9 , respectively).Conjunctivitis was reported in 84/241 (38.2%) patients. The proportion of eosinophilia (>500/mm 3 ) during follow-up (57%) was higher than at baseline (33.7%) (n=172, p<10 -6 ).Dupilumab was stopped in 42 cases, 27 of which were due to an AE. Limitations:No control group, missing data. Conclusion:This real-life study demonstrated results similar to clinical trials, with regard to dupilumab effectiveness, but revealed a higher frequency of conjunctivitis and eosinophilia.

Dear Editor, A previously healthy 57-year-old woman presented with fever (39 °C) lasting for 4 days, and dry cough and rash appeared 2 days before. Diffuse fixed erythematous blanching maculopapular lesions were present, asymptomatic over the limbs and trunk, with burning sensation over the palms (a, b). She denied any drug intake, excepting paracetamol for fever.Thorax computed tomography scan was typical of COVID-19; nasopharyngeal swab polymerase chain reaction (PCR) confirmed SARS-CoV-2. Infectious enquiry was otherwise negative. Skin biopsy specimen showed slight spongiosis, basal cell vacuolation and mild perivascular lymphocytic infiltrate (c). PCR on whole-skin biopsy specimen was negative for SARS-CoV-2.Fever and rash resolved within 9 days, dry cough within 2 weeks. Urticarial and chilblain-like lesions have been reported in patients with COVID-19, but other phenotypes could be observed. 1,2 In our patient an immune reaction to the virus is possible.

IMPORTANCE VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) is a recently described severe adult-onset autoinflammatory disease that is associated with myeloid lineage-restricted ubiquitin-activating enzyme 1 (UBA1) somatic variations that primarily affect the skin (Sweet syndrome), cartilage, and bone marrow. Skin symptoms have been poorly described.OBJECTIVE To better describe clinical and pathological skin manifestations and their pathophysiology in VEXAS syndrome. DESIGN, SETTING, AND PARTICIPANTSThis multicenter retrospective case series study of clinical and histological features of 8 patients with VEXAS syndrome and skin involvement was conducted in France from December 2007 to March 2021, with molecular data obtained from March to April 2022. Any UBA1 variations were detected by Sanger or next-generation sequencing that was performed on bone marrow and formalin-fixed paraffin-embedded tissue sections of skin lesion biopsies.RESULTS All 8 patients were men, and the median age at symptom onset was 65.5 years (interquartile range, 54-76 years). All patients had neutrophilic dermatosis skin lesions, including tender red or violaceous papules, sometimes edematous, without fever, arthralgia, recurrence or pathergy, inflammatory edematous papules on the neck and trunk (sometimes umbilicated), and firm erythematous purpuric or pigmented infiltrated plaques and nodules. Three patients had livedo racemosa. The infiltrates were perivascular and consisted of mature neutrophils with leukocytoclasia, which were admixed with myeloperoxidase-positive CD163-positive myeloid cells with indented nuclei and lymphoid cells in all cases. A sequencing analysis of paired bone marrow samples and skin lesion biopsies identified the same loss-of-function UBA1 variation in both samples for all patients.CONCLUSIONS AND RELEVANCE This case series study describes the different clinical presentations of skin lesions found in VEXAS syndrome, which is characterized histologically by neutrophilic dermatosis. The findings suggested that the dermal infiltrates seen in VEXAS skin lesions are derived from the pathological myeloid clone. This suggests that using therapies that target the pathological clone may be effective in the long-term management of the disease.