Viral exanthems: An update on laboratory testing of the adult patient

Dengue: updates for dermatologists on the world's fastest-growing vector-borne disease

Dengue is the world's fastest-growing vector borne disease and has significant epidemic potential in suitable climates. Recent disease models incorporating climate change scenarios predict geographic expansion across the globe, including parts of the United States and Europe. It will be increasingly important in the next decade for dermatologists to become familiar with dengue, as it commonly manifests with rashes, which can be used to aid diagnosis. In this review, we discuss dengue for general dermatologists, specifically focusing on its cutaneous manifestations, epidemiology, diagnosis, treatment, and prevention. As dengue continues to spread in both endemic and new locations, dermatologists may have a larger role in the timely diagnosis and management of this disease.

Prevalence of cutaneous manifestations in COVID-19: A meta-analysis

The global epidemic of coronavirus disease 2019 (COVID-19) endangers more and more people. Many studies on cutaneous manifestations related to COVID-19 have emerged, but their prevalence has varied widely. The objective of this study was to conduct a meta-analysis estimating the prevalence of skin manifestations in COVID-19. Four databases PubMed, Web of Science, CBM, and CNKI were searched, and the results were screened by two reviewers. A random-effects model was used to evaluate the overall prevalence. Heterogeneity was assessed by I² . Further subgroup analyses were conducted by region, sample size, sex, age, and severity of COVID-19. A funnel plot and Egger's test were performed to assess publication bias. The pooled prevalence of cutaneous manifestation of 61 089 patients in 33 studies was 5.6% (95% confidence intervals [CI] = 0.040-0.076, I²  = 98.3%). Severity of COVID-19 was probably the source of heterogeneity. Studies with sample size <200 report higher prevalence estimates (10.2%). The prevalence of detailed types was as follows: maculopapular rash 2%, livedoid lesions 1.4%, petechial lesions 1.1%, urticaria 0.8%, pernio-like lesions 0.5%, vesicular lesions 0.3%. Petechial lesions and livedoid lesions contain a higher proportion of severe patients than other skin manifestations. The prevalence rates of pernio-like lesions, urticaria and petechial lesions vary greatly in different regions.

Prevalence of arboviruses and other infectious causes of skin rash in patients treated at a tertiary health unit in the Brazilian Amazon

BACKGROUND

In the clinical course of diseases such as arboviruses, skin rashes may appear, as is often seen in other infectious diseases. The aim of this study was to estimate the prevalence of arboviruses and other infectious causes of skin rash in a tertiary health unit in Manaus, Amazonas state, Western Brazilian Amazon.

METHODOLOGY/PRINCIPAL FINDINGS

This was a cross-sectional study of patients presenting with rash who sought care at Fundação de Medicina Tropical Dr. Heitor Vieira Dourado (FMT-HVD) from February 2018 to May 2019. Individuals of either gender, aged over 18 years, were invited to participate voluntarily. Infection by Zika virus (ZIKV), dengue virus (DENV), chikungunya virus (CHIKV), Mayaro virus (MAYV), Oropouche virus (OROV) and measles was evaluated using RT-qPCR (real-time polymerase chain reaction). Immunodiagnostic tests for EBV, CMV, HIV, syphilis, rubella and measles were also performed. A total of 340 participants were included, most were female (228, 67.1%) with an average age of 36.5 years (SD ± 12.2 years). The highest prevalence was of ZIKV monoinfections (65.3%, 222/340), followed by DENV (0.9%, 3/340) and CHIKV infection (0.3%, 1/340). No cases of MAYV, OROV or rubella were found. Other causes of skin rash were detected: measles (2.9%, 10/340), parvovirus B19 (0.9% 3/340), HIV (0.3%, 1/340) and syphilis 0.6% (2/340). The co-infections identified were ZIKV+HIV (0.3%, 1/340), ZIKV+measles (0.3%, 1/340), ZIKV+parvovirus B19 (0.3%, 1/340), ZIKV+EBV (0.3%, 1/340), EBV+parvovirus B19 (0.3%, 1/340), CMV+parvovirus B19 (0.6%, 2/340), CMV+syphilis (0.3%, 1/340), ZIKV+EBV+parvovirus B19 (0.3%, 1/340) and CMV+EBV+parvovirus B19 (0.9%, 3/340). Approximately one quarter of patients had no defined cause for their skin rash (25.3%, 86/340).

CONCLUSIONS

Despite the benign clinical evolution of most of the diseases diagnosed in this series of cases, syndromic surveillance of diseases such as syphilis and HIV are of utmost importance. Periodic serosurveillance might also aid in evaluating the trends of endemic diseases and eventual outbreaks.

Annular drug eruptions

Cutaneous adverse drug reactions are undesirable cutaneous changes caused by medications. Drug eruptions can mimic a wide range of dermatoses that include exanthematous (morbilliform), urticarial, pustular, bullous, papulosquamous, or granulomatous lesions, and sometimes these eruptions may present with annular, polycyclic, or polymorphous configurations. The correct identification of a cutaneous drug eruption depends on a high index of suspicion, detailed medication exposure history, chronologic evaluation of the causal relationships between drug exposures and eruptions, and the exclusion of other infectious or idiopathic diseases. Most drug eruptions are annoying but self-limited, usually resolving after the withdrawal of the causative agents. Rarely, patients have severe cutaneous adverse reactions, such as Stevens-Johnson syndrome, toxic epidermal necrolysis, and drug reaction with eosinophilia and systemic symptoms (DRESS), which are potentially lethal adverse drug reactions that involve the skin and mucous membranes and may also damage internal organs. Prompt recognition of the alarming signs of severe cutaneous adverse reactions and providing adequate treatment may thus be life-saving. We present the main clinical presentations, histopathology, possible implicated medications, and treatment of cutaneous adverse drug reactions that can present in annular configurations.

Beyond arboviruses: A multicenter study to evaluate differential diagnosis of rash diseases and acute febrile illness cases in Rio de Janeiro, Brazil

Introduction

A wide variety of viruses can cause rash diseases (RDs) or acute febrile illness (AFIs) in children, adolescents and adults; however, approximately 19% of RD cases and 40% of AFI cases remain without a defined etiology. Parvovirus B19 (B19V) and herpesvirus infection can also cause RD and/or AFI, and in some risk groups, these infections can become persistent (or latent) and may require hospital treatment. Since these infections do not have mandatory reporting, they can be hidden by other diseases, such as those caused by arboviruses (e.g., dengue virus). In this context, the aim of this study was to pursue the differential laboratory diagnoses of B19V and herpesvirus infections in patients with RD and AFI, without a defined etiology, seen in hospitals and/or reference centers for infectious diseases in Rio de Janeiro.

Methods

A total of 114 participants were enrolled in the study, including 54 children and 60 adults. B19V infection was assessed by real-time PCR (qPCR) and ELISA (anti-B19V IgM and IgG). EBV was assessed through qPCR, and betaherpesviruses (HCMV, HHV-6 and HHV-7) were assessed through multiplex qPCR. Sociodemographic and clinical data were obtained from the medical record data of these participants.

Results

The median age of children with RD was 2 years (interquartile range (IQR): 5), and 55.6% were male. Among adults with AFI, the median age was 38 years (IQR: 21), and 56.7% were female. Regarding RD patients, viral prevalence (and load) were 5.5%(104IU/mL), 3.4%(104IU/mL), 5.5%(104IU/mL) and 11.1%(105IU/mL) for B19V, EBV, HCMV and HHV-6 infection, respectively, and in AFI patients they were 6.6%(105IU/mL), 1.6%(103IU/mL), 3.3%(104IU/mL) for B19V, HCMV and HHV-6, respectively. HHV-7 was not detected in RD or AFI patients.

Conclusion

These results suggest the importance of including B19V and herpesviruses in the differential laboratory diagnoses for patients with RD and AFI, not only for epidemiological purposes but also for the proper management of the patient.

Cutaneous manifestations in children with SARS-CoV-2 infection and/or COVID-19: what do we know after 10 months under this pandemic?

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global crisis. However, cutaneous manifestations in children with SARS-CoV-2 infection have received little attention.

OBJECTIVE

Our study was aimed to present clinical and cutaneous manifestations of children with SARS-CoV-2 and to provide the basis for early diagnosis.

METHODS

We analyzed the clinical data of COVID-19 infected (CI) children worldwide from December 2019 to October 6, 2020, by using search terms "COVID-19," "SARS-CoV-2," "Coronavirus" in combination with "cutaneous," "lesion," "rash," "skin," "dermatology," "epidermis," "dermis," "multisystem inflammatory syndrome." We collected and analyzed the general information, clinical symptoms, cutaneous manifestations, laboratory examination results, history of close contact with CI patients or suspected CI patients, and outcome in CI children.

RESULTS

Among 90 CI children, there were 46 boys (59%) and 32 girls (41%). Erythema was the most frequent lesion, followed by conjunctivitis, and edematous lesions. Face was the most commonly affected location including lips, conjunctivae, tongue, eyes, and eyelids. Sixty-three (73.3%) patients had multisystem inflammatory syndrome (MIS-C). As for clinical symptoms, 70 (81.4%) CI children suffered fever, and 34 (39.5%) patients had lung involvement. Meanwhile, 65.1% of patients had cardiac involvement, 4.7% of patients were asymptomatic, and 71.6% of patients received intravenous immunoglobulin, as well as 31.1% of CI children received systemic corticosteroids. Three children were dead. The most frequent route of infection was familial clustering. As silent virus carriers of CI children, it is important to find out the clinical and cutaneous manifestations in CI children to prevent and control COVID-19 transmission.

Cutaneous manifestations related to the COVID-19 pandemic: a review article

BACKGROUND

Skin lesions are either caused by COVID-19 disease or they can be due to other driving forces related to the COVID-19 pandemic.

AIM

Considering the fact that the reported data in different articles for the type and prevalence of skin manifestations related to the COVID-19 pandemic are inconsistent, we have described the mechanism and type of skin lesions related to the COVID-19 pandemic.

METHODS

In this review article, we have searched the Medline database (PubMed) for the combination of the following key terms "Dermatological Manifestation", "cutaneous Manifestation", "Skin Manifestation", "COVID-19", "SARS-CoV-2".

RESULTS

The prevalence of skin manifestations related to COVID-19 ranged from 0.2% to 20%. The majority of these skin lesions are maculopapular eruptions. The skin presentations related to the COVID-19 pandemic are described below. Traumatic skin conditions such as dermatitis in individuals, especially those with allergies, might initiate secondary to over-washing or rinsing with inappropriate detergents. Also, inappropriate use of personal protective equipment (mask-gloves-shield) can trigger skin lesions on the face and hands or aggravate the lesions of acne, seborrhoeic dermatitis, eczema, etc. Furthermore, cutaneous adverse drug reactions may occur during hospitalization or outpatient treatment of COVID-19 patients. Also, psychocutaneous disorders due to acute stress can trigger or deteriorate several skin manifestations. Moreover, COVID-19 prevalence and course may be changed in patients with autoimmune or chronic inflammatory underlying skin disorders such as psoriasis, lupus erythematosus, pemphigus, scleroderma who are on immunosuppressive or biological medications to control their disorders.

CONCLUSION

Due to the various dimensions of skin organ involvement and the large population affected, long-term skin conditions following this pandemic can be a lot more problematic than it appears. Serious preventive measures and medical supports are necessary to avoid skin disorders from becoming permanent or even chronic.

Serum β2-microglobulin may be a viral biomarker by analyzing children with upper respiratory tract infections and exanthem subitum: a retrospective study

Background

Due to the lack of effective and feasible viral biomarkers to distinguish viral infection from bacterial infection, children often receive unnecessary antibiotic treatment. To identify serum β2-microglobulin that distinguishes bacterial upper respiratory tract infection from viral upper respiratory tract infection and exanthem subitum in children.

Methods

This retrospective study was conducted from January 1, 2019 to September 30, 2020 in Yancheng Third People’s Hospital. Children with upper respiratory tract infection and exanthem subitum were recruited. The concentration of serum β2-microglobulin in the viral and bacterial infection groups were statistically analyzed.

Results

A total of 291 children included 36 with bacterial upper respiratory tract infection (median age, 13 months; 44.4% female), 197 with viral upper respiratory tract infection (median age, 12 months; 43.7% female) and 58 with exanthem subitum (median age, 13 months; 37.9% female). When the concentration of β2-microglobulin was 2.4mg/L, the sensitivity to distinguish viral from bacterial upper respiratory tract infection was 81.2% (95% CI [75.1–86.4%]), and the specificity was 80.6% (95% CI [64.0–91.8]%). When the cutoff was 2.91 mg/L, the sensitivity of β2-microglobulin to distinguish exanthem subitum from bacterial upper respiratory tract infection was 94.8% (95% CI [85.6–98.9]%), and the specificity was 100% (95% CI [90.3–100]%).

Conclusions

Serum β2-microglobulin may be a significant biological indicator in children with upper respiratory tract infection and exanthem subitum.

Cutaneous Manifestations of COVID-19: A Systematic Review

Objective: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is currently a pandemic. Although pulmonary health has been the primary focus of studies during the early days of COVID-19, development of a comprehensive understanding of this emergent disease requires knowledge of all possible disease manifestations in affected patients. This Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)-compliant review focuses on cutaneous manifestations reported in COVID-19 patients. Approach: Literature review was conducted using the PubMed database to examine various cutaneous manifestations related to the SARS-CoV-2 infection. Published articles (n = 56) related to search criteria from the onset of the COVID-19 pandemic to June 30, 2020, were included. The primary literature articles included in this study were mainly from France, Spain, Italy, and the United Kingdom. Results: Unique to many other symptoms of COVID-19, its cutaneous manifestations have been found in people of all age groups, including children. The cutaneous manifestations of COVID-19 are varied and include maculopapular, chilblain-like, urticarial, vesicular, livedoid, and petechial lesions. In addition, rashes are common in multisystem inflammatory syndrome in children, a new and serious health condition that shares symptoms with Kawasaki disease and is likely related to COVID-19. In addition, personal protective equipment-related skin wounds are of serious concern since broken cutaneous barriers can create an opening for potential COVID-19 infections. Innovation and Conclusion: As this virus continues to spread silently, mainly through asymptomatic carriers, an accurate and rapid identification of these cutaneous manifestations may be vital to early diagnosis and lead to possible better prognosis in COVID-19 patients. This systematic review and photo atlas provide a detailed analysis of the skin pathologies related to COVID-19. Study of these cutaneous manifestations and their pathogenesis, as well their significance in human health will help define COVID-19 in its entirety, which is a prerequisite to its effective management.

A Novel Human Skin Tissue Model To Study Varicella-Zoster Virus and Human Cytomegalovirus

The herpesviruses varicella-zoster virus (VZV) and human cytomegalovirus (HCMV) are endemic to humans. VZV causes varicella (chicken pox) and herpes zoster (shingles), while HCMV causes serious disease in immunocompromised patients and neonates. More effective, less toxic antivirals are needed, necessitating better models to study these viruses and evaluate antivirals. Previously, VZV and HCMV models used fetal tissue; here, we developed an adult human skin model to study VZV and HCMV in culture and in vivo While VZV is known to grow in skin, it was unknown whether skin could support an HCMV infection. We used TB40/E HCMV and POka VZV strains to evaluate virus tropism in skin organ culture (SOC) and skin xenograft mouse models. Adult human skin from reduction mammoplasties was prepared for culture on NetWells or mouse implantation. In SOC, VZV infected the epidermis and HCMV infected the dermis. Specifically, HCMV infected fibroblasts, endothelial cells, and hematopoietic cells, with some infected cells able to transfer infection. VZV and HCMV mouse models were developed by subcutaneous transplantation of skin into SCID/beige or athymic nude mice at 2 independent sites. Viruses were inoculated directly into one xenograft, and widespread infection was observed for VZV and HCMV. Notably, we detected VZV- and HCMV-infected cells in the contralateral, uninoculated xenografts, suggesting dissemination from infected xenografts occurred. For the first time, we showed HCMV successfully grows in adult human skin, as does VZV. Thus, this novel system may provide a much-needed preclinical small-animal model for HCMV and VZV and, potentially, other human-restricted viruses.IMPORTANCE Varicella-zoster virus and human cytomegalovirus infect a majority of the global population. While they often cause mild disease, serious illness and complications can arise. Unfortunately, there are few effective drugs to treat these viruses, and many are toxic. To complicate this, these viruses are restricted to replication in human cells and tissues, making them difficult to study in traditional animal models. Current models rely heavily on fetal tissues, can be prohibitively expensive, and are often complicated to generate. While fetal tissue models provide helpful insights, it is necessary to study human viruses in human tissue systems to fully understand these viruses and adequately evaluate novel antivirals. Adult human skin is an appropriate model for these viruses because many target cells are present, including basal keratinocytes, fibroblasts, dendritic cells, and lymphocytes. Skin models, in culture and xenografts in immunodeficient mice, have potential for research on viral pathogenesis, tissue tropism, dissemination, and therapy.

Measles skin rash: Infection of lymphoid and myeloid cells in the dermis precedes viral dissemination to the epidermis

Measles is characterized by fever and a maculopapular skin rash, which is accompanied by immune clearance of measles virus (MV)-infected cells. Histopathological analyses of skin biopsies from humans and non-human primates (NHPs) with measles rash have identified MV-infected keratinocytes and mononuclear cells in the epidermis, around hair follicles and near sebaceous glands. Here, we address the pathogenesis of measles skin rash by combining data from experimentally infected NHPs, ex vivo infection of human skin sheets and in vitro infection of primary human keratinocytes. Analysis of NHP skin samples collected at different time points following MV inoculation demonstrated that infection in the skin precedes onset of rash by several days. MV infection was detected in lymphoid and myeloid cells in the dermis before dissemination to the epidermal leukocytes and keratinocytes. These data were in good concordance with ex vivo MV infections of human skin sheets, in which dermal cells were more targeted than the epidermal cells. To address viral dissemination to the epidermis and to determine whether the dissemination is receptor-dependent, we performed experimental infections of primary keratinocytes collected from healthy donors. These experiments demonstrated that MV infection of keratinocytes is mainly nectin-4-dependent, and differentiated keratinocytes, which express higher levels of nectin-4, are more susceptible to MV infection than proliferating keratinocytes. Based on these data, we propose a model to explain measles skin rash: migrating MV-infected lymphocytes initiate the infection of dermal skin-resident CD150⁺ immune cells. The infection is subsequently disseminated from the dermal papillae to nectin-4⁺ keratinocytes in the basal epidermis. Lateral spread of MV infection is observed in the superficial epidermis, most likely due to the higher level of nectin-4 expression on differentiated keratinocytes. Finally, MV-infected cells are cleared by infiltrating immune cells, causing hyperemia and edema, which give the appearance of morbilliform skin rash.

Several viral infections are associated with skin rash, including parvovirus B19, human herpesvirus type 6, dengue virus and rubella virus. However, the archetype virus infection that leads to skin rash is measles. Although all of these viral exanthemata often appear similar, their pathogenesis is different. In the case of measles, the appearance of skin rash is a sign that the immune system is clearing MV-infected cells from the skin. How the virus reaches the skin and is locally disseminated remains unknown. Here, we combine observations and expertise from pathologists, dermatologists, virologists and immunologists to delineate the pathogenesis of measles skin rash. We show that MV infection of dermal myeloid and lymphoid cells precedes viral dissemination to the epidermal leukocytes and keratinocytes. We speculate that immune-mediated clearance of these infected cells results in hyperemia and edema, explaining the redness of the skin and the slightly elevated spots of the morbilliform rash.

Going Viral 2019: Zika, Chikungunya, and Dengue

Chikungunya and Zika virus infections are emerging diseases in the Americas, and dengue continues to be the most prevalent arthropod-borne virus in the world. These arbovirus diseases may spread by endemic transmission or as travel-related infections and have rapidly expanded their geographic distribution secondary to vector spread. All 3 share a similar clinical picture that includes a maculopapular rash. Zika is characterized by pruritic rash, low-grade fever, and arthralgia. Congenital nervous system malformations are a growing public-health concern. Chikungunya distinctive dermatologic manifestations include facial melanosis and bullous eruption. Dengue bleeding complications may be life-threatening and require inpatient management.

Differential diagnosis of late-type reactions to injected local anaesthetics: Inflammation at the injection site is the only indicator of allergic hypersensitivity

BACKGROUND

Anaphylaxis-like reactions developing within a few minutes are the most frequent complications of subcutaneous or submucosal injections of local anaesthetics (LAs), and topically applied LAs are potential contact allergens. In addition, injected LAs have been reported to induce delayed reactions, including local inflammation at the injection site, and various general symptoms.

OBJECTIVES

To assess the frequency and symptoms of late-type hypersensitivity occurring several hours after LA injections.

METHODS

We retrospectively evaluated clinical data and test results from all patients referred to our allergy clinic in a period of 20 years for diagnostic work-up of LA-associated late-type reactions.

RESULTS

Of 202 patients reporting symptoms with onset at least 1 hour after LA injection, 40 had cutaneous inflammation confined to the injection site, and 162 reported various systemic symptoms. LA hypersensitivity could be excluded in all patients with systemic complaints by means of skin testing and subsequent subcutaneous provocation. In 8 of the 40 patients (20%) with local inflammatory reactions, late-type allergic LA hypersensitivity was confirmed.

CONCLUSIONS

Late-type LA allergy commonly causes inflammatory skin reactions confined to the injection site. Conversely, LAs are highly unlikely to trigger delayed systemic symptoms such as urticarial or exanthematous skin eruptions.

Emergence of chikungunya and Zika in a municipality endemic to dengue, Santa Luzia, MG, Brazil, 2015-2017

INTRODUCTION

The recent circulation of arboviruses transmitted by vectors, such as dengue, chikungunya, and Zika, is concerning due to the high morbidity rates, clinical complications, and increased demand on health services. The objective of this study was to analyze the clinical and epidemiological aspects of an epidemic caused by arboviruses in the municipality of Santa Luzia, Minas Gerais, Brazil.

METHODS

Longitudinal study of patients with acute febrile disease and suspected arbovirus infection reported to Brazilian Notifiable Disease Information System (Sistema de Informação de Agravos de Notificação) from the epidemiological week 44 of 2015 to epidemiological week 52 of 2016. Patients with confirmed chikungunya were followed-up for 18 months and those with Zika for 15 months. Additionally, we analyzed and described the temporal distribution of confirmed cases of these arboviruses in this municipality.

RESULTS

Overall 3,531 arboviruses cases, including 3,481 (98.7%) cases of dengue, 38 (1.0%) cases of chikungunya, and 12 (0.3%) cases of Zika were confirmed. The highest incidence of arbovirus infection occurred in the first quarter of 2016 (epidemiological week 7 to 14). The most frequent symptoms were for dengue, which included fever, headache, retro-orbital pain, and exanthema. Chikungunya infection was associated with fever, myalgia, arthralgia, and rash while Zika infection with pruritus and rash.

CONCLUSIONS

Given the similarities in the initial clinical profiles of these arboviruses, it is important to perform a detailed clinical analysis, laboratory diagnosis, and patient follow-up.