Lack of association between chilblains outbreak and severe acute respiratory syndrome coronavirus 2: Histologic and serologic findings from a new immunoassay

Defining the short-term and long-term skin manifestations of COVID-19: insights after more than three years of the pandemic

AIM

This review aimed to assess the impact of coronavirus disease 2019 (COVID-19) on skin health to establish a classification of the skin lesions that occur most frequently during the disease and whether a particular category of skin damage is more likely to occur both in the short term and in the long term.

METHODS

We conducted a literature search of the PubMed database. Ultimately, 109 articles were included in this review. The exact phrases∕syntax and connectors used for the database search∕query were as follows: "Coronavirus and skin", "COVID-19 and skin", "SARS-CoV-2 and skin", "Coronavirus cutaneous manifestations", "COVID-19 cutaneous manifestations", "SARS-CoV-2 cutaneous manifestations", "Coronavirus dermatology", "SARS-CoV-2 and dermatology", "COVID-19 and dermatology", "COVID-19 and skin eruption", "Coronavirus and skin rash", "COVID-19 and hair", "Coronavirus and hair", "Coronavirus and nails", "SARS-CoV-2 and hair", and "SARS-CoV-2 and nails". Only articles with abstracts referring strictly to cutaneous manifestations of COVID-19 were chosen. Articles without abstracts were not considered.

RESULTS

We established six of the most frequently reported clinical patterns associated with COVID-19 and their probability of occurring during COVID-19 disease evolution based on the current literature reports. We did not identify the particular types of skin lesions that are most prone to long-term persistence; most such cases are rare, and no conclusion can be drawn based on them.

CONCLUSIONS

Apart from classified COVID-19-related skin disorders, this pandemic has been a challenge for dermatologists and a wide range of cutaneous side effects related to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) treatments have been reported. We are aware of other polymorphic clinical presentations, with novel data being reported periodically, but the pathophysiological mechanisms and evolution are largely unknown.

Lack of association between pandemic chilblains and SARS-CoV-2 infection

An increased incidence of chilblains has been observed during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic and attributed to viral infection. Direct evidence of this relationship has been limited, however, as most cases do not have molecular evidence of prior SARS-CoV-2 infection with PCR or antibodies. We enrolled a cohort of 23 patients who were diagnosed and managed as having SARS-CoV-2-associated skin eruptions (including 21 pandemic chilblains [PC]) during the first wave of the pandemic in Connecticut. Antibody responses were determined through endpoint titration enzyme-linked immunosorbent assay and serum epitope repertoire analysis. T cell responses to SARS-CoV-2 were assessed by T cell receptor sequencing and in vitro SARS-CoV-2 antigen-specific peptide stimulation assays. Immunohistochemical and PCR studies of PC biopsies and tissue microarrays for evidence of SARS-CoV-2 were performed. Among patients diagnosed and managed as "covid toes" during the pandemic, we find a percentage of prior SARS-CoV-2 infection (9.5%) that approximates background seroprevalence (8.5%) at the time. Immunohistochemistry studies suggest that SARS-CoV-2 staining in PC biopsies may not be from SARS-CoV-2. Our results do not support SARS-CoV-2 as the causative agent of pandemic chilblains; however, our study does not exclude the possibility of SARS-CoV-2 seronegative abortive infections.

Experience with Cutaneous Manifestations in COVID-19 Patients during the Pandemic

After the beginning of the SARS-CoV-2 pandemic, our dermatology department created a multidisciplinary unit to manage patients with cutaneous manifestations associated with COVID-19. With the objective of identifying skin lesions in patients with suspected COVID-19 and evaluating possible associations with systemic involvement, other infectious agents and coagulation disorders, we carried out a prospective observational study that included all patients that attended our COVID-19 dermatology clinic with a multidisciplinary protocol. A total of 63 patients (mean 34.6 years) were enrolled between May 2020 and February 2021. Overall, 27 patients (42.9%) had a positive COVID-19 test, and 74.6% had COVID-19 clinical signs. The most common skin lesion was maculopapular rash (36.5%), predominantly seen in male (54.2%) and older patients (42 vs. 30 years), followed by chilblain-like lesions (20.6%) in younger patients (13.9 vs. 20.9 years) who were predominantly barefoot at home (69.2%); these patients exhibited a tendency towards a negative COVID-19 test. A total of 12 patients (19.1%) had positive serology for herpesvirus 6 (IgM or IgG). We conclude that the COVID-19-associated skin lesions we observed were similar to those previously described. Questions as to the underlying mechanisms remain. Interferon, possibly aided by cold exposure, may cause perniosis-like lesions. Other cutaneous manifestations were similar to those caused by other viruses, suggesting that SARS-CoV-2 may reactivate or facilitate other viral infections.

Type I interferon response and vascular alteration in chilblain-like lesions during the COVID-19 outbreak

Background

The outbreak of chilblain‐like lesions (CLL) during the COVID‐19 pandemic has been reported extensively, potentially related to SARS‐CoV‐2 infection, yet its underlying pathophysiology is unclear.

Objectives

To study skin and blood endothelial and immune system activation in CLL in comparison with healthy controls and seasonal chilblains (SC), defined as cold‐induced sporadic chilblains occurring during 2015 and 2019 with exclusion of chilblain lupus.

Methods

This observational study was conducted during 9–16 April 2020 at Saint‐Louis Hospital, Paris, France. All patients referred with CLL seen during this period of the COVID‐19 pandemic were included in this study. We excluded patients with a history of chilblains or chilblain lupus. Fifty patients were included.

Results

Histological patterns were similar and transcriptomic signatures overlapped in both the CLL and SC groups, with type I interferon polarization and a cytotoxic–natural killer gene signature. CLL were characterized by higher IgA tissue deposition and more significant transcriptomic activation of complement and angiogenesis factors compared with SC. We observed in CLL a systemic immune response associated with IgA antineutrophil cytoplasmic antibodies in 73% of patients, and elevated type I interferon blood signature in comparison with healthy controls. Finally, using blood biomarkers related to endothelial dysfunction and activation, and to angiogenesis or endothelial progenitor cell mobilization, we confirmed endothelial dysfunction in CLL.

Conclusions

Our findings support an activation loop in the skin in CLL associated with endothelial alteration and immune infiltration of cytotoxic and type I IFN‐polarized cells leading to clinical manifestations.

Cutaneous Pathology of COVID-19 as a Window into Immunologic Mechanisms of Disease

Many skin manifestations of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection reflect activation of cutaneous and systemic immune responses involving effector pathways of both the innate and adaptive arms of the immune system. This article reviews evidence from the recent clinical and scientific literature that informs the current understanding of the consequences of coronavirus disease 2019 (COVID-19)-induced immune cell activation, as relevant to dermatology. Topics include the clinical consequences of autoantibody production in patients with COVID-19, immunologic evidence for chilblains as a manifestation of SARS-CoV-2 infection, and the relationship between type I interferons and COVID-19 disease severity.

Are the chilblain-like lesions observed during the COVID-19 pandemic due to severe acute respiratory syndrome coronavirus 2? Systematic review and meta-analysis

The expansion of the COVID‐19 pandemic has been accompanied by numerous reports of chilblain‐like lesions (CLL) in different countries; however, the pathogenesis of these lesions is still unclear. This systematic review and meta‐analysis aimed to assess the prevalence of COVID‐19 (diagnosed using PCR and/or serology) in patients with CLL. We undertook a literature search in PubMed, Embase, and Scopus (to 15 March 2021), including studies that reported on the number of patients with CLL with positive PCR and/or serology for severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) or with a clinical suspicion of COVID‐19. Regardless of data heterogeneity, a random‐effects model was used to pool prevalence estimates. The meta‐analysis included 63 original studies, involving 2919 cases of CLL. A subgroup of these patients underwent diagnostic tests for COVID‐19 (PCR: n = 1154, 39.5%; serology: n = 943, 32.3%). The pooled prevalence of COVID‐19 in the overall sample and in the subgroup who were tested for COVID‐19 was, respectively: (i) positive PCR: 2.6% [95% confidence interval (CI) 1.9% to 3.4%] and 5.5% (95% CI, 3.7–7.7%); (ii) positive serology for SARS‐CoV‐2: 7.2% (95% CI, 4.7–10.2%) and 11.8% (95% CI, 7.9–16.3%); and (iii) positive PCR and/or serology, 15.2% (95% CI, 10.4–20.7%) and 7.5% (95% CI, 5.1–10.3%). Altogether, a small proportion of diagnostic tests for SARS‐CoV‐2, both PCR and serologies, show positive results in patients with CLL.

Nails and COVID-19 - A comprehensive review of clinical findings and treatment

The SARS‐CoV‐2 infection, responsible for COVID‐19, has raised the interest for infection‐associated muco‐cutaneous symptoms. While dermatologic symptoms in general gained an increasing awareness, affection of the nail organ has been mentioned only recently. We provide a narrative review on COVID‐19 manifestation on the nail organ and add symptoms induced by personal protective measures and SARS‐CoV‐2 vaccination. Available treatment options are discussed.

Skin lesions in children during the first wave of the SARS-CoV-2 pandemic

Background

Cutaneous manifestations have been included in COVID-19 patients’ clinical spectrum. Our objective was to determine the association between skin lesions in children and SARS-CoV2 infection, analyzing others possible infectious/autoimmune etiologies.

Material and methods

Observational, multicenter, cross-sectional study, about children with skin manifestations from April to May 2020. The diagnosis of SARS-CoV2 was performed by PCR in nasopharyngeal exudate and/or presence of antibodies by serology.

Results

Sixty-two children were included, 9 (14.5%) presented positive antibodies to SARS-CoV-2, with no positive PCR to SARS-Cov-2 in those patients in whom it was made. Patients with positive serology to SARS-CoV-2 presented chilblains and/or vesicular-bullous skin lesions more frequently (66.7% vs. 24.5%, p = 0.019). Generalized, urticarial and maculopapular rash was more common in patients with negative antibodies (37.7 vs. 0%, p = 0.047), others pathogens were isolated in 41.5% of these patients. There were no significant differences in the positivity for autoantibodies between both groups.

Conclusion

In our study, the presence of chilblains-like and/or vesicular lesions were significantly related to SARS-CoV2 previous contact.

[Skin lesions in children during the first wave of the SARS-CoV-2 pandemic]

Introducción

Las manifestaciones cutáneas se han incluido en el espectro clínico de los pacientes con COVID-19. Nuestro objetivo fue determinar la asociación entre las lesiones cutáneas observadas en niños durante la primera ola de la pandemia y la infección por SARS-CoV-2, analizando otras posibles etiologías infecciosas o autoinmunes.

Material y métodos

Estudio observacional, multicéntrico, de corte transversal, desarrollado en niños con manifestaciones cutáneas desde abril hasta mayo de 2020. La determinación de SARS-CoV-2 se realizó mediante PCR en exudado nasofaríngeo y/o serología.

Resultados

Se seleccionó a 62 niños; 9 (14,5%) presentaron serología positiva para SARS-CoV-2, siendo la PCR negativa en todos los casos en los que se realizó. Los pacientes con serología positiva para SARS-CoV-2 presentaron con más frecuencia lesiones pernióticas y/o vesiculosas (66,7 vs. 24,5%; p = 0,019). El exantema generalizado, urticarial y maculopapuloso fue más habitual en el grupo de pacientes con serología negativa (37,7 vs. 0%; p = 0,047); se aislaron otros patógenos en el 41,5%. No hubo diferencias significativas en cuanto a la positividad de autoanticuerpos entre ambos grupos.

Conclusión

En nuestro estudio, las lesiones de tipo perniosis o vesiculosas se relacionaron significativamente con el contacto previo con SARS-CoV-2.

Management of Difficult-to-Treat Warts: Traditional and New Approaches

Warts are regularly treated by dermatologists, and while many respond readily to first-line treatments, others may represent a therapeutic challenge. Large, deep, numerous, and extensive warts; treatment-resistant lesions with higher risk for side effects, such as hypopigmentation; or patients unable to tolerate or comply with our treatment regimen, may need alternative treatment options. In this work we review the characteristics of select modalities that should be considered for difficult-to-treat warts. We discuss efficacy and tolerability data as well as practical features that can guide us to select the best treatment for every scenario. Novel approaches, still in an investigational phase, are also discussed to illustrate potential future directions of wart treatment.

Idiopathic perniosis presenting as acral purpuric lesions: Clustering of cases before COVID-19 pandemic and their comparison with chilblain like lesions reported in the literature

Perniosis/chilblains are the acral inflammatory skin lesions developing in susceptible individuals as an abnormal reaction to cold. In the absence of a discernible cause, it is labeled as idiopathic perniosis (IP). With the ongoing COVID-19 pandemic, there was an upsurge of reports of chilblain like lesions (CLL) especially in young patients possibly implicated to the SARS-CoV-2 virus. Twelve clinically suspected and histopathologically confirmed cases of IP seen from November 2019 through February 2020 were retrospectively recruited. Clinical, dermoscopic, and histopathological characteristics of these were reviewed and compared with CLL reported in the literature. Mean age of patients was 26.58 ± 15.18 years with an equal male to female ratio. Characteristic histopathology findings were spongiosis (100%), dermal edema (100%), perivascular lymphocytic infiltrate (100%) with peri-eccrine accentuation (66.7%), keratinocyte necrosis (50%), focal basal vacuolar damage (58.3%), and lymphocytic vasculitis (58.3%). Significant dermoscopy findings were variable background color ranging from dull red and violaceous to copper red and brown orange, coiled vessels (44.4%) and orange-red structureless areas (63.9%). Lesions over palms and soles preferentially had white dots/clods and lines (38.9%). There appears no exclusive histopathological as well as dermoscopy features of CLL and IP, yet certain clues can be appreciated. Keratinocyte necrosis and severe dermal edema favors IP, whereas fibrin thrombi with involvement of both superficial and deep dermal vessels favor CLL. Dermoscopically presence of irregular, linear or branching vessels, red/purple dots and clods and gray brown reticule supports CLL while white dots/clods and lines supports IP.

Evaluation of Humoral Immunity to SARS-CoV-2: Diagnostic Value of a New Multiplex Addressable Laser Bead Immunoassay

Despite efforts to develop anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody (Ab) immunoassays, reliable serological methods are still needed. We developed a multiplex addressable laser bead immunoassay (ALBIA) to detect and quantify anti-Spike S1 and nucleocapsid N Abs. Recombinant S1 and N proteins were bound to fluorescent beads (ALBIA-IgG-S1/N). Abs were revealed using class-specific anti-human Ig Abs. The performances of the test were analyzed on 575 serum samples including 192 from SARS-CoV-2 polymerase chain reaction-confirmed patients, 13 from seasonal coronaviruses, 70 from different inflammatory/autoimmune diseases, and 300 from healthy donors. Anti-S1 IgM were detected by monoplex ALBIA-IgM-S1. Comparison with chemiluminescent assays or enzyme-linked immunosorbent assays was performed using commercial tests. Multiplex ALBIA-IgG-S1/N was effective in detecting and quantifying anti-SARS-CoV-2 IgG Abs. Two weeks after first symptoms, sensitivity and specificity were 97.7 and 98.0% (anti-S1), and 100 and 98.7% (anti-N), respectively. Agreement with commercial tests was good to excellent, with a higher sensitivity of ALBIA. ALBIA-IgG-S1/N was positive in 53% of patients up to day 7, and in 75% between days 7 and 13. For ALBIA-IgM-S1, sensitivity and specificity were 74.4 and 98.7%, respectively. Patients in intensive care units had higher IgG Ab levels (Mann-Whitney test, p < 0.05). ALBIA provides a robust method for exploring humoral immunity to SARS-CoV-2. Serology should be performed after 2 weeks following first symptoms, when all COVID-19 (coronavirus disease 2019) patients had at least one anti-S1 or anti-N IgG Ab, illustrating the interest of a multiplex test.