BACKGROUND: Erythema multiforme (EM) is an uncommon cutaneous reaction pattern characterised by panepidermal keratinocyte apoptosis with lymphocytic satellitosis, and is reported in domestic animal species, livestock and rarely ferrets.
OBJECTIVE: The aim of this study was to analyse the spectrum of cutaneous clinical and histological features in ferrets with EM and to evaluate history and treatment outcomes.
METHODS: Five client-owned ferrets with biopsy-confirmed EM.
METHODS: Retrospective review of electronic medical records and histopathological reports from 2002 to 2021. Tissue blocks, haematoxylin and eosin re-cuts, and unstained slides were collected to review EM lesions and evaluate for infectious agents with special stains. Immunohistochemical staining was performed to assess cases for viral pathogens.
RESULTS: Panepidermal cytotoxic dermatitis consistent with EM was identified in all cases and involved haired skin in four of five and mucous membranes in one of five ferrets. Skin lesions included variably pruritic alopecia, erythema, scaling, crusts and erosions/ulcerations. Histological features included primarily parakeratotic hyperkeratosis, panepidermal keratinocyte apoptosis, lymphocytic satellitosis and interface dermatitis. Superficial colonisation by bacteria, yeasts or by both was a common finding. Four of five ferrets had concurrent adrenal disease, one of which had resolution of skin lesions with deslorelin acetate treatment.
CONCLUSIONS: Awareness of the distinct clinical and histological features is key to the diagnosis of EM in ferrets. Clinical resolution was observed with gonadotropin-releasing hormone agonists in two cases, suggesting that adrenal disease should be ruled out as a potential trigger of EM in ferrets.
BACKGROUND: L\'érythème polymorphe (EP) est un pattern réactionnel cutané rare caractérisé par une apoptose panépidermique des kératinocytes, associée à une satellitose lymphocytaire ; il est rapporté chez les animaux domestiques, le bétail et rarement les furets. HYPOTHÈSE/OBJECTIFS: Analyser l’ensemble des présentations cliniques et histologiques cutanées chez les furets atteints d\'EP, et évaluer l\'anamnèse et les résultats thérapeutiques.
UNASSIGNED: Cinq furets appartenant à des clients atteints d’un EP confirmé par biopsie. MATÉRIELS ET MÉTHODES: Examen rétrospectif des dossiers médicaux électroniques et des rapports histopathologiques de 2002 à 2021. Des blocs de tissus, des re-coupes colorées à l’hématoxyline et à l’éosine et des lames non colorées ont été collectés pour examiner les lésions d’EP et détecter la présence d’agents infectieux avec des colorants spéciaux. Une coloration immunohistochimique a été réalisée pour mettre en évidence les agents pathogènes viraux. RÉSULTATS: Une dermatite cytotoxique panépidermique compatible avec un EP a été identifiée dans tous les cas ; elle concernait la peau velue de quatre des cinq furets et les muqueuses chez l\'un des cinq furets. Les lésions cutanées consistaient de manière variable en une alopécie prurigineuse, un érythème, un squamosis, des croûtes et des érosions voire des ulcérations. Les caractéristiques histologiques comprenaient principalement une hyperkératose parakératosique, une apoptose panépidermique des kératinocytes, une satellitose lymphocytaire et une dermatite d\'interface. La colonisation superficielle par des bactéries et/ou des levures était courante. Quatre des cinq furets souffraient d’une maladie surrénalienne concomitante, pour l’un d’eux la résolution des lésions cutanées a été obtenue avec un traitement à l\'acétate de desloréline.
UNASSIGNED: La connaissance des caractéristiques cliniques et histologiques distinctes est essentielle au diagnostic de l\'EP chez les furets. Une résolution clinique a été observée avec les agonistes de l\'hormone de libération des gonadotrophines dans deux cas, ce qui suggère que la maladie surrénalienne devrait être recherchée comme déclencheur possible de l\'EP chez les furets.
INTRODUCCIÓN: El eritema multiforme (EM) es un patrón de reacción cutánea poco común caracterizado por apoptosis de queratinocitos panepidérmicos con satelitosis linfocítica, y se reporta en especies de animales domésticos, ganado y raramente en hurones. HIPÓTESIS/OBJETIVOS: Analizar el espectro de características clínicas e histológicas cutáneas en hurones con EM, y evaluar la historia y los resultados del tratamiento. ANIMALES: cinco hurones de propietarios particulares con EM confirmado por biopsia. MATERIALES Y MÉTODOS: revisión retrospectiva de historiales clínicos electrónicos e informes histopatológicos de 2002 a 2021. Se recolectaron bloques de tejido, cortes de hematoxilina y eosina y portaobjetos sin teñir para revisar las lesiones de EM y evaluar agentes infecciosos con tinciones especiales. Se realizó inmunohistoquímica para evaluar posibles patógenos virales. RESULTADOS: Se identificó dermatitis citotóxica panepidérmica consistente con EM en todos los casos y afectaba a piel en cuatro de cinco hurones y a las membranas mucosas en uno de cinco hurones. Las lesiones cutáneas incluyeron alopecia pruriginosa variable, eritema, descamación, costras y erosiones/ulceraciones. Las características histológicas incluyeron principalmente hiperqueratosis paraqueratósica, apoptosis de queratinocitos panepidérmicos, satelitosis linfocítica y dermatitis de interfase. La colonización superficial por bacterias, levaduras o ambas fue un hallazgo común. Cuatro de cinco hurones tenían enfermedad suprarrenal concurrente, uno de los cuales tuvo resolución de las lesiones cutáneas con tratamiento con acetato de deslorelina. CONCLUSIONES Y RELEVANCIA CLÍNICA: El conocimiento de las distintas características clínicas e histológicas es clave para el diagnóstico de EM en hurones. Se observó resolución clínica con agonistas de la hormona liberadora de gonadotropina en dos casos, lo que sugiere que la enfermedad suprarrenal debe descartarse como un desencadenante potencial de EM en hurones.
UNASSIGNED: Das Erythema multiforme (EM) ist ein unübliches Reaktionsmuster der Haut, welches durch panepidermale Keratinozyten-Apoptose mit Satellitose von Lymphozyten charakterisiert wird und bei Haustieren, Farmtieren und selten beim Frettchen beschrieben wurde.
UNASSIGNED: Die Analyse des Spektrums der kutanen klinischen und histologischen Merkmale bei Frettchen mit EM und die Evaluierung der Anamnese und des Behandlungserfolges.
UNASSIGNED: Fünf Frettchen in Privatbesitz mit durch Biopsie bestätigtem EM.
UNASSIGNED: Eine retrospektive Review elektronischer Patientenkarteien und histopathologische Berichte von 2002 bis 2021. Gewebeblöcke, Hämatoxylin und Eosin Neuschnitte und ungefärbte Objektträger wurden zur Durchsicht von EM-Läsionen gesammelt und mit Spezialfärbungen auf infektiöse Keime durchgesehen. Es wurden immunhistochemische Färbungen durchgeführt, um die Fälle auf virale Pathogene durchzusehen.
UNASSIGNED: In allen Fällen wurde eine panepidermale zytotoxische Dermatitis, die mit einem EM konsistent war, identifiziert, welche behaarte Haut bei vier von fünf bzw die Schleimhäute bei einem von fünf Frettchen involvierte. Die Hautveränderungen waren unterschiedlich und bestanden aus juckender Alopezie, Erythem, Schuppenbildung, Krusten und Erosionen/Ulzera. Die histologischen Merkmale bestanden primär aus parakeratotischer Hyperkeratose, panepidermaler Keratinozyten-Apoptose, Satellitose der Lymphozyten und einer Interface Dermatitis. Eine oberflächliche Besiedelung durch Bakterien, Hefen oder beidem war ein häufiger Befund. Vier von fünf Frettchen hatten gleichzeitig eine Erkrankung der Nebennieren, wobei bei einem die Hautveränderungen mittels Deslorelin Acetat Behandlung verschwanden.
UNASSIGNED: Das Bewusstsein der klassischen klinischen und histologischen Merkmale ist ein Schlüssel zur Diagnose von EM beim Frettchen. Eine klinische Abheilung wurde mit Gonadotropin-Hormon Agonisten in zwei Fällen beobachtet, was darauf hinweist, dass eine Erkrankung der Nebennieren als potenzieller Trigger von EM beim Frettchen ausgeschlossen werden sollte.
背景: 多形紅斑(EM)は、リンパ球衛生現象を伴う汎表皮ケラチノサイトのアポトーシスを特徴とする珍しい皮膚反応パターンであり、飼育動物種、家畜、まれにフェレットで報告されている。 仮説/目的: 本研究の目的は、EMを発症したフェレットの皮膚臨床および組織学的特徴のスペクトルを解析し、病歴および治療成績を評価することであった。 対象動物: 生検で EM が確認されたオーナー所有フェレット 5 頭。 材料と方法: 2002年から2021年までの電子カルテおよび病理組織報告書をレトロスペクティブレビューした。組織ブロック、ヘマトキシリン・エオジン再切断、未染色スライドを収集し、EM病変の検討と特殊染色による感染因子の評価を行った。免疫組織化学染色は、ウイルス性病原体の症例を評価するために実施した。 結果: EMと一致する汎表皮細胞毒性皮膚炎が全例で確認され、5例中4例が毛のある皮膚に、5例中1例に粘膜に病変を認めた。皮膚病変は、様々な痒みを伴う脱毛、紅斑、鱗屑、痂皮、びらん/潰瘍を含んでいた。組織学的特徴としては、主に不全角化性角化亢進、汎表皮角化細胞アポトーシス、リンパ球衛星現象、境界部皮膚炎が挙げられた。細菌、酵母、あるいはその両方による表面的なコロニー形成は、一般的な所見であった。5匹のフェレットのうち4匹は副腎疾患を併発していたが、そのうち1匹は酢酸デスロレリンによる治療で皮膚病変が消失した。 結論と臨床的意義: フェレットにおけるEMの診断には、臨床的および組織学的特徴を明確に認存することが重要である。2例ではゴナドトロピン放出ホルモン作動薬により臨床的な消失が認められたことから、フェレットにおけるEMの潜在的な誘因として副腎疾患を除外する必要があることが示唆された。.
背景: 多形红斑(EM)是一种罕见的皮肤反应模式，其特征是全表皮角质形成细胞凋亡伴淋巴细胞性卫星变性，在家养动物、养殖动物和少数雪貂中均有报道。 假设/目的: 分析EM雪貂的皮肤临床和组织学特征，并评估病史和治疗结果。 动物: 五只客户所有的雪貂，经活检证实为EM。 材料和方法: 对2002年至2021的电子病历和组织病理学报告进行回顾性审查。收集组织块、苏木精和伊红重切，以及未染色的载玻片，以审查EM病变并评估具有特殊染色的感染源。免疫组织化学染色用于评估病毒病原体的病例。 结果: 在所有病例中都发现了与EM一致的泛皮肤性细胞毒性皮炎，五只雪貂中有四只涉及毛发皮肤，五只中有一只涉及粘膜。皮肤病变包括各种瘙痒性脱毛、红斑、脱屑、结痂和糜烂/溃疡。组织学特征主要包括角化不全性角化过度、全表皮角质形成细胞凋亡、淋巴细胞性卫星变性和界面皮炎。细菌、酵母或两者的表面定植常见。五只雪貂中有四只同时患有肾上腺疾病，其中一只雪貂的皮肤病变通过醋酸地洛瑞林治疗得以缓解。 结论和临床相关性: 对雪貂不同的临床和组织学特征的认识是诊断EM的关键。在两例病例中，使用促性腺激素释放激素激动剂观察到临床缓解，这表明应排除肾上腺疾病作为雪貂EM的潜在诱因。.
UNASSIGNED: O eritema multiforme (EM) é um padrão de reação cutânea incomum caracterizado por apoptose panepidérmica e sateliose linfocítica, e é relatado em espécies de animais domésticos, de produção e raramente em furões. HIPÓTESE/OBJETIVOS: Analisar o espectro de características clínicas e histológicas em furões com EM, e avaliar o histórico e resultado dos tratamentos.
UNASSIGNED: Cinco furões de clientes com EM confirmado por biópsia. MATERIAIS E MÉTODOS: Estudo retrospectivo de prontuários eletrônicos e laudos histopatológicos de 2002 a 2021. Blocos de biópsia, recortes corados em hematoxilina-eosina, e lâminas não coradas foram coletados para revisão das lesões de EM e pesquisa de agentes infecciosos com corantes especiais. Utilizou-se imuno-histoquímica para avaliar a presença de patógenos virais.
RESULTS: Dermatite citotóxica panepidérmica consistente com EM foi identificada em todos os casos e afetaram a pele pilosa em quatro de cinco e as mucosas de um de cinco furões. Os sinais clínicos incluíram alopecia variavelmente pruriginosa, eritema, descamação, crostas e erosões/ulcerações. As características histológicas incluíram hiperqueratose paraqueratótica, apoptose panepidérmica de queratinócitos, sateliose linfocítica e dermatite de interface. Colonização superficial por bactérias, leveduras ou ambas foi um achado comum. Quatro de cinco furões apresentaram doença adrenal concomitante, e um deles apresentou resolução das lesões cutâneas após tratamento com acetato de deslorelina. CONCLUSÕES E RELEVÂNCIA CLÍNICA: O conhecimento acerca das características clínicas e histológicas é crucial no diagnóstico do EM em furões. Resolução clínica foi observada após uso de hormônio agonista de liberação de gonadotropina em dois casos, sugerindo que a adrenopatia deve ser descartada como um potencial gatilho do EM em furões.

BACKGROUND: Since the 2002 SCAR study, erythema multiforme (EM), a post-infectious disease, has been distinguished from Stevens-Johnson syndrome (SJS), drug-induced. Nevertheless, EM cases are still reported in the French pharmacovigilance database (FPDB).
OBJECTIVE: To describe EM reported in the FPDB and to compare the quality and the characteristics of the reports.
METHODS: This retrospective observational study selected all EM cases reported in the FPDB over two periods: period 1 (P1, 2008-2009) and period 2 (P2, 2018-2019). Inclusion criteria were 1) a diagnosis of clinically typical EM and/or validated by a dermatologist; 2) a reported date of onset of the reaction; and 3) a precise chronology of drug exposure. Cases were classified confirmed EM (typical acral target lesions and/or validation by a dermatologist) and possible EM (not-otherwise-specified target lesions, isolated mucosal involvement, doubtful with SJS). We concluded possible drug-induced EM when EM was confirmed, with onset ranging from 5 to 28 days without an alternative cause.
RESULTS: Among 182 selected reports, 140 (77%) were analyzed. Of these, 67 (48%) presented a more likely alternative diagnosis than EM. Of the 73 reports of EM cases finally included (P1, n=41; P2, n=32), 36 (49%) had a probable non-drug cause and 28 (38%) were associated with only drugs with an onset time ≤4 days and/or ≥29 days. Possible drug-induced EM was retained in 9 cases (6% of evaluable reports). Etiological work-up was more often performed in period 2 than 1 (53.1% vs 29.3%, P=0.04), and the time to onset from 5 to 28 days was more frequent in period 2 (59.2% vs 40%, P=0.04).
CONCLUSIONS: This study suggests that possible drug-induced EM is rare. Many reports describe \"polymorphic\" rashes inappropriately concluded as EM or post-infectious EM with unsuitable drug accountability subject to protopathic bias.

暂无摘要。

After coronavirus disease 2019 (COVID-19) caused a global pandemic, vaccines were rapidly developed to control the spread of the virus. Although they were effective in most of the cases at protecting people from becoming seriously ill and being hospitalized, they showed side effects, too. Among other adverse vaccine reactions, cutaneous eruptions following SARS-CoV-2 have been described in the literature, but they are not well-characterized yet. We described the morphology and timing of the spectrum of cutaneous reactions following most of the COVID-19 vaccines available in Italy, which were observed in outpatients referred to our non-invasive diagnostic clinic. Most of these reactions appeared after the second or third COVID-19 vaccine dose (most of them after mRNA COVID-19 vaccines). Our data support that cutaneous reactions to COVID-19 vaccination are generally self-limited; in addition, history of allergic reaction to a specific food, medicine or vaccine should not discourage vaccination in the general population, although patients with immune dysregulation should be accurately selected and monitored. Further research is necessary to better assess the true prevalence and preventive measures of skin reactions to COVID-19 vaccination.

Allopurinol should be started at lower doses in patients with chronic kidney disease (CKD) to avoid adverse effects. We examined the risk of severe cutaneous reactions in older adults with CKD who were newly prescribed allopurinol at varied doses.
Population-based cohort study using linked health care databases.
Patients in Ontario, Canada (2008-2019) aged ≥66 years, with an estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m2, and who were new users of allopurinol.
A new prescription for allopurinol >100 mg/d versus a dose ≤100 mg/d.
The primary outcome was a hospital visit with a severe cutaneous reaction within 180 days of starting allopurinol. Secondary outcomes included all-cause hospitalization and all-cause mortality.
The exposure and referent groups were balanced on indicators of baseline health using inverse probability of treatment weighting on the propensity score. Weighted risk ratios (RR) were obtained using modified Poisson regression and weighted risk differences (RD) using binomial regression.
Of 47,315 patients (median age, 76 years; median eGFR, 45 mL/min/1.73 m2), 55% started allopurinol at >100 mg/d. Starting allopurinol at >100 versus ≤100 mg/d was associated with an increased risk of a severe cutaneous reaction: number of events (weighted), 103 of 25,802 (0.40%) versus 46 of 25,816 (0.18%), respectively (weighted RR, 2.25 [95% CI, 1.50-3.37]; weighted RD, 0.22% [95% CI, 0.12%-0.32%]. Starting allopurinol at >100 versus ≤100 mg/d was associated with an increased risk of all-cause hospitalization but not with all-cause mortality.
This study was underpowered to detect risk differences in the association of allopurinol dose with outcomes across eGFR categories (ie, 45-59, 30-44, and <30 mL/min/1.73 m2).
Older patients with CKD who started allopurinol at >100 mg/d versus ≤100 mg/d were twice as likely to visit a hospital with a severe cutaneous reaction in the next 180 days.

Cutaneous immune-related adverse events (cirAEs) are the most prevalent complication to arise from immunotherapy and cause significant morbidity. We aimed to determine the spectrum, timing, clinical features, and outcomes of cirAEs by conducting an observational pharmacovigilance study using VigiBase, the World Health Organization\'s global database of individual case safety reports from over 130 member countries (ClinicalTrials.gov, number NCT04898751). We compared adverse event reporting in patients who received immune checkpoint inhibitors (91,323 adverse events) with those of the full reporting database (18,919,358 adverse events). There were 10,933 cases of cirAEs within 51 distinct dermatologic types, with 27 specific eruptions with disproportionate signal represented (information component [IC]025 > 0). Of these 27 eruptions, there were eight cirAEs with n > 100 reports, including vitiligo (IC025 = 4.87), bullous pemphigoid (IC025 = 4.08), lichenoid dermatitis (IC025 = 3.69), erythema multiforme (IC025 = 1.03), toxic epidermal necrolysis (IC025 = 0.95), Stevens‒Johnson syndrome (IC025 = 0.41), drug eruption (IC025 = 0.11), and eczematous dermatitis (IC025 = 0.11). There were differences in time to onset after immune checkpoint inhibitor initiation, with a median of approximately 1 month (erythema multiforme, Stevens‒Johnson syndrome, and toxic epidermal necrolysis), 2 months (drug eruption and eczematous dermatitis), 4 months (lichenoid dermatitis), and 5‒6 months (bullous pemphigoid and vitiligo). CirAEs are diverse, dependent on cancer type, and have distinct and different onset times that are linked to the cirAE subtype.

BACKGROUND: Cutaneous reactions after COVID-19 vaccination have been commonly reported; however, histopathologic features and clinical correlations have not been well characterized.
METHODS: We evaluated for a history of skin biopsy all reports of reactions associated with COVID-19 vaccination identified in an international registry. When histopathology reports were available, we categorized them by reaction patterns.
RESULTS: Of 803 vaccine reactions reported, 58 (7%) cases had biopsy reports available for review. The most common histopathologic reaction pattern was spongiotic dermatitis, which clinically ranged from robust papules with overlying crust, to pityriasis rosea-like eruptions, to pink papules with fine scale. We propose the acronym \"V-REPP\" (vaccine-related eruption of papules and plaques) for this spectrum. Other clinical patterns included bullous pemphigoid-like (n = 12), dermal hypersensitivity (n = 4), herpes zoster (n = 4), lichen planus-like (n = 4), pernio (n = 3), urticarial (n = 2), neutrophilic dermatosis (n = 2), leukocytoclastic vasculitis (n = 2), morbilliform (n = 2), delayed large local reactions (n = 2), erythromelalgia (n = 1), and other (n = 5).
CONCLUSIONS: Cases in which histopathology was available represented a minority of registry entries. Analysis of registry data cannot measure incidence.
CONCLUSIONS: Clinical and histopathologic correlation allowed for categorization of cutaneous reactions to the COVID-19 vaccine. We propose defining a subset of vaccine-related eruption of papules and plaques, as well as 12 other patterns, following COVID-19 vaccination.

BACKGROUND: The distinction between epidermal necrolysis [EN; including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN) and overlap syndrome] and erythema multiforme major (EMM) in children is confusing. We aimed to better describe and compare these entities.
METHODS: This French retrospective multicentre study included children ≤18 years old referred for EN or EMM between 1 January 2008 and 1 March 2019. According to pictures, children were reclassified into TEN/overlap, SJS or EMM/unclassified (SJS/EMM) groups and compared for epidemiological and clinical data, triggers, histology and follow-up.
RESULTS: We included 62 children [43 boys, median age 10 years (range 3-18)]: 16 with TEN/overlap, 11 SJS and 35 EMM. The main aetiologies were drugs in EN and infections (especially Mycoplasma pneumoniae) in EMM (P < 0.001), but 35% of cases remained idiopathic (TEN/overlap, 47%; SJS, 24%; EMM, 34%). The typical target lesions predominated in EMM (P < 0.001), the trunk was more often affected in EN (P < 0.001), and the body surface area involved was more extensive in EN (P < 0.001). Mucosal involvement did not differ between the groups. Two patients with idiopathic TEN died. Histology of EMM and EN showed similar features. The recurrence rate was 42% with EMM, 7% with TEN/overlap and 0 with SJS (P < 0.001). Sequelae occurred in 75% of EN but involved 55% of EMM.
CONCLUSIONS: Clinical features of EN and EMM appeared well demarcated, with few overlapping cases. Idiopathic forms were frequent, especially for EN, meaning that a wide and thorough infectious screening, repeated if needed, is indicated for all paediatric cases of EN/EMM without any trigger drug. We propose a comprehensive panel of investigations which could be a standard work-up in such situation. Sequelae affected both EN and EMM.

Plasmacytoid dendritic cells (pDCs) constitute a subset of dendritic cells known to be the \"professional\" interferon type I (IFN-I) producers. pDCs play an important role in antiviral immunity, as well as linking innate and adaptive immunity. Under normal conditions pDCs are not present in skin. They are shown to be a part of the inflammatory infiltrate in different skin conditions including erythema multiforme (EM). This condition is considered to be a cell-mediated immune reaction to a wide variety of agents, most commonly herpes simplex virus. Nevertheless, the pathophysiology of EM still remains unclear. In this study, we grouped 32 biopsies from 30 patients diagnosed with EM, based on their etiology and analyzed the density and distribution of CD123 positive pDCs. In all cases we observed a greatly increased number of pDCs in the dermal inflammatory infiltrate. Virally-induced EM (by herpes simplex virus (HSV) and other viruses) was more likely to have a significantly higher number of pDCs compared to non-virally associated EM. Hence, we think that pDCs play a key role in the pathogenesis of EM independent of etiology and may play an increased role in virally-associated cases. Further studies on pDCs would clarify their importance in EM and improve our understanding of the pathophysiology of this disease.

Cutaneous reactions after messenger RNA (mRNA)-based COVID-19 vaccines have been reported but are not well characterized.
To evaluate the morphology and timing of cutaneous reactions after mRNA COVID-19 vaccines.
A provider-facing registry-based study collected cases of cutaneous manifestations after COVID-19 vaccination.
From December 2020 to February 2021, we recorded 414 cutaneous reactions to mRNA COVID-19 vaccines from Moderna (83%) and Pfizer (17%). Delayed large local reactions were most common, followed by local injection site reactions, urticarial eruptions, and morbilliform eruptions. Forty-three percent of patients with first-dose reactions experienced second-dose recurrence. Additional less common reactions included pernio/chilblains, cosmetic filler reactions, zoster, herpes simplex flares, and pityriasis rosea-like reactions.
Registry analysis does not measure incidence. Morphologic misclassification is possible.
We report a spectrum of cutaneous reactions after mRNA COVID-19 vaccines. We observed some dermatologic reactions to Moderna and Pfizer vaccines that mimicked SARS-CoV-2 infection itself, such as pernio/chilblains. Most patients with first-dose reactions did not have a second-dose reaction and serious adverse events did not develop in any of the patients in the registry after the first or second dose. Our data support that cutaneous reactions to COVID-19 vaccination are generally minor and self-limited, and should not discourage vaccination.