Immunohistochemistry in the Diagnosis of Cutaneous Viral Infections—Part I. Cutaneous Viral Infections by Herpesviruses and Papillomaviruses

Clinical, histopathological and ultrastructural features of human monkeypox infection in the 2022 outbreak: report of a case with immunohistochemistry for vaccinia virus

We provide a full description of the clinical, histopathological, immunohistochemical and ultrastructural features of the current human monkeypox virus. A skin snip was obtained in a HIV-infected patient in the wake of the monkeypox outbreak in Spain. Immunohistochemistry was strongly positive for anti-vaccinia virus. Under electron microscopy, mature viruses and virions were clearly visible.

Selective retention of virus-specific tissue-resident T cells in healed skin after recovery from herpes zoster

Herpes zoster is a localized skin infection caused by reactivation of latent varicella-zoster virus. Tissue-resident T cells likely control skin infections. Zoster provides a unique opportunity to determine if focal reinfection of human skin boosts local or disseminated antigen-specific tissue-resident T cells. Here, we show virus-specific T cells are retained over one year in serial samples of rash site and contralateral unaffected skin of individuals recovered from zoster. Consistent with zoster resolution, viral DNA is largely undetectable on skin from day 90 and virus-specific B and T cells decline in blood. In skin, there is selective infiltration and long-term persistence of varicella-zoster virus-specific T cells in the rash site relative to the contralateral site. The skin T cell infiltrates express the canonical tissue-resident T cell markers CD69 and CD103. These findings show that zoster promotes spatially-restricted long-term retention of antigen-specific tissue-resident T cells in previously infected skin.

Fever and acute urticaria in a young male patient

A 23-year-old man presented to our emergency department with a new onset of low-grade fever associated with diffuse itching urticarial rash localized to his trunk and upper limbs. He denied respiratory and gastrointestinal symptoms. Peripheral oxygen saturation was 98% at room ambient. His past medical history was unremarkable, and he was not taking any medications. No history of allergies was reported. He denied traveling abroad, contact with animals, ingesting raw meat or fish, or taking medicine. Laboratory results showed leukopenia with lymphocytopenia and normal C-reactive protein value. Eosinophils were normal. Hepatic and renal tests were all within the normal range. He was vaccinated with 3 doses of Comirnaty vaccine with no adverse reactions. Lung ultrasound showed A pattern without pleural effusion. The patient was discharged with oral steroids (prednisone 25 mg for three days with a progressive reduction in 10 days) and oral antihistamine (bilastine 10 mg daily for 10 days), and acetaminophen 1 gr if fever above 37.5°C, with complete resolution of the rash without sequelae in 10 days.

COVID-19 and cutaneous manifestations: Two cases and a review of the literature

COVID-19 can affect multiple organs, including skin. A wide range of skin manifestations have been reported in literature. Six main phenotypes have been identified: i) urticarial rash, ii) confluent erythematous/maculopapular/morbilliform rash, iii) papulovesicular exanthem, iv) a chilblain-like acral pattern, v) a livedo reticularis/racemosa-like pattern, and vi) a purpuric vasculitic pattern. The pathogenetic mechanism is still not completely clear, but a role of hyperactive immune response, complement activation and microvascular injury have been postulated. The only correlation between the cutaneous phenotype and the severity of COVID-19 has been observed in the case of chilblain-like acral lesions, that is generally associated with the benign/subclinical course of COVID-19. Herein, we report two cases of SARS-CoV- 2 infection in patients who developed cutaneous manifestations that completely solved with systemic steroids and antihistamines. The first case is a female patient not vaccinated for SARS-CoV-2 with COVID-19 associated pneumonia, while the second case is a vaccinated female patient with only skin manifestations.

Immunohistochemical Detection of SARS-CoV-2 Antigens by Single and Multiple Immunohistochemistry

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can be demonstrated in tissue sections by immunohistochemistry (IHC), which has the power to localize in bright field specific antigens in cells and tissues. The use of double or triple immunostains is capable of highlighting which cells are infected and/or the relationship of infected cell with other cells and tissue structures. In addition, immunoenzymatic multi-staining permits the simultaneous identification, localization, and enumeration of different cellular epitopes. Moreover, this method improves analytical precision, decreasing the time required for morphometric quantification, maximizing the information obtained from a single slide of paraffin-embedded tissue.

SARS-CoV-2, COVID-19, skin and immunology - What do we know so far?

The pandemic condition coronavirus disease (COVID-19), caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can take asymptomatic, mild, moderate, and severe courses. COVID-19 affects primarily the respiratory airways leading to dry cough, fever, myalgia, headache, fatigue, and diarrhea and can end up in interstitial pneumonia and severe respiratory failure. Reports about the manifestation of various skin lesions and lesions of the vascular system in some subgroups of SARS-CoV-2-positive patients as such features outside the respiratory sphere, are rapidly emerging. Vesicular, urticarial, and maculopapular eruptions and livedo, necrosis, and other vasculitis forms have been reported most frequently in association with SARS-CoV-2 infection. In order to update information gained, we provide a systematic overview of the skin lesions described in COVID-19 patients, discuss potential causative factors, and describe differential diagnostic evaluations. Moreover, we summarize current knowledge about immunologic, clinical, and histologic features of virus- and drug-induced lesions of the skin and changes to the vascular system in order to transfer this knowledge to potential mechanisms induced by SARS-CoV-2.

Cutaneous Manifestations in Confirmed COVID-19 Patients: A Systematic Review

There have been increasing reports of skin manifestations in COVID-19 patients. We conducted a systematic review and included manuscripts describing patients with positive RT-PCR coronavirus testing from nasopharyngeal swabs who also developed cutaneous manifestations. A total of 655 patients were selected, with different types of skin rashes: Erythematous maculopapular (n = 250), vascular (n = 146), vesicular (n = 99), urticarial (n = 98), erythema multiforme/generalized pustular figurate erythema/Stevens-Johnson syndrome (n = 22), ocular/periocular (n = 14), polymorphic pattern (n = 9), generalized pruritus (n = 8), Kawasaki disease (n = 5), atypical erythema nodosum (n = 3), and atypical Sweet syndrome (n = 1). Chilblain-like lesions were more frequent in the younger population and were linked to a milder disease course, while fixed livedo racemosa and retiform purpura appeared in older patients and seemed to predict a more severe prognosis. For vesicular rashes, PCR determined the presence of herpesviruses in the vesicle fluid, which raised the possibility of herpesvirus co-infections. The erythema-multiforme-like pattern, generalized pustular figurate erythema and Stevens-Johnson syndrome were most frequently linked to hydroxychloroquine intake. A positive PCR determination of SARS-COV-2 from conjunctival swabs suggest that eye discharge can also be contagious. These cutaneous manifestations may aid in identifying otherwise asymptomatic COVID-19 carriers in some cases or predict a more severe evolution in others.

Clinical and histological characterization of vesicular COVID-19 rashes: a prospective study in a tertiary care hospital

COVID‐19 is an infectious disease caused by severe acute respiratory coronavirus 2 (SARS‐CoV‐2). Vesicular skin rashes have been reported as associated with COVID‐19, but there is little information about this cutaneous manifestation. We designed a prospective observational study of patients diagnosed with COVID‐19 who had vesicular lesions. Clinical characterization of skin findings was conducted by dermatologists. When possible, histological analysis and detection of SARS‐CoV‐2 in the content of the vesicles was performed. In total, 24 patients were included. A disseminated pattern was found in 18 patients (75%), and a localized pattern was found in 6 (25%). Median duration of the skin rash was 10 days. Of the 24 patients, 19 (79.2%) developed the skin rash after the onset of COVID‐19 symptoms. Histological examination in two patients was consistent with viral infection, SARS‐CoV‐2 was not detected in four patients. This single‐centre study shows the clinical characteristics of vesicular skin rashes in patients with COVID‐19.

Approach to skin and soft tissue infections in non-HIV immunocompromised hosts

PURPOSE OF REVIEW

Skin and soft tissue infections are frequent contributors to morbidity and mortality in the immunocompromised host. This article reviews the changing epidemiology and clinical manifestations of the most common cutaneous pathogens in non-HIV immunocompromised hosts, including patients with solid organ transplants, stem cell transplants, solid tumors, hematologic malignancies, and receiving chronic immunosuppressive therapy for inflammatory disorders.

RECENT FINDINGS

Defects in the innate or adaptive immune response can predispose the immunocompromised host to certain cutaneous infections in a predictive fashion. Cutaneous lesions in patients with neutrophil defects are commonly due to bacteria, Candida, or invasive molds. Skin lesions in patients with cellular or humoral immunodeficiencies can be due to encapsulated bacteria, Nocardia, mycobacteria, endemic fungal infections, herpesviruses, or parasites. Skin lesions may reflect primary inoculation or, more commonly, disseminated infection. Tissue samples for microscopy, culture, and histopathology are critical to making an accurate diagnosis given the nonspecific and heterogeneous appearance of these skin lesions due to a blunted immune response.

SUMMARY

As the population of non-HIV immunosuppressed hosts expands with advances in medical therapies, the frequency and variety of cutaneous diseases in these hosts will increase.

Immunohistochemistry Is Rarely Justified for the Diagnosis of Viral Infections

OBJECTIVES

To determine the utility of immunohistochemistry (IHC) for the diagnosis of viral infections in surgical pathology specimens lacking characteristic viral cytopathic effects.

METHODS

Five years of cases at an academic medical center were reviewed for the use of IHC to detect cytomegalovirus (CMV), herpes simplex virus 1 and 2 (HSV-1 and HSV-2), varicella zoster virus (VZV), adenovirus, or polyomavirus (ie, BK or JC).

RESULTS

In total, 1,636 viral IHC stains were ordered on 1,099 specimens from 957 cases. Altogether, 134 (8.2%) stains were positive, including 59 (7.9%) of 749 for CMV, 34 (8.9%) of 384 for HSV-1 and HSV-2, 16 (11.5%) of 139 for VZV, three (1.4%) of 210 for adenovirus, and 22 (14.3%) of 154 for polyomavirus. In 101 (75.4%) of 134 cases, viral cytopathic effect (VCPE) was readily identifiable on H&E slides. No significant changes in clinical care occurred in any of the cases without definitive VCPE that had positive staining cells on IHC.

CONCLUSIONS

These findings suggest that IHC for viral infections without a high degree of clinical or histologic suspicion is unnecessary in most cases.

Viral Infections

Despite major advances in basic and applied research and the availability of several vaccines, viral diseases still account for a large proportion of the human infectious disease burden. Many viruses cause self-limiting and relatively mild infections, but several, including human immunodeficiency virus and influenza virus, are responsible for millions of deaths every year throughout the world. Several factors contribute to the enormous impact that viruses have on human health. For example, there are very few therapeutic options available for the treatment of viral infections, and many of those that are available possess a limited spectrum of activity or are designed for the treatment of diseases caused by specific viruses (e.g., oseltamivir is intended for the treatment of influenza only). In addition, the rapid evolution of viruses has led to the emergence of drug-resistant strains against which no currently available therapeutics are effective. Coupled with these and other issues are the appearance of never before seen viruses and the emergence of known but previously underappreciated viruses. Since the beginning of the twenty-first century, numerous “new” viruses, including the coronaviruses responsible for severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), the 2009 pandemic influenza A virus, and Lujo hemorrhagic fever virus, have made their debut and have proved to be formidable threats to human health. Recently, the appearance of Ebola virus (Zaire ebolavirus) in West Africa, a region that has not previously seen an outbreak of this virus, was marked by an epidemic that afflicted nearly 30,000 individuals and killed more than 11,000 of those who were infected. Most recently, the far-reaching and rapid spread of Zika virus, a mosquito-borne virus that was discovered in the 1940s in Uganda, in the Western Hemisphere has invoked considerable public and scientific attention and has given rise to perhaps the largest concerted effort by scientists to rapidly develop a vaccine to halt the transmission of a virus. Each of these points underscores the importance of further research into improved surveillance, diagnosis, treatment, and prevention of viral diseases.

Bullous, pseudobullous, & pustular dermatoses

Several dermatoses are typified by the formation of spaces (blisters; bullae) within or beneath the epidermis. These may be acellular or filled with particular species of inflammatory cells. Etiological categories include infectious, immune-mediated, genetic, drug-related, and idiopathic lesions. Examples of such disorders include impetigo, Herpes virus infections, pemphigus, bullous pemphigoid and pemphigoid gestationis, epidermolysis bullosa acquisita, IgA-related dermatoses, inherited epidermolysis bullosa variants, Hailey-Hailey disease, and porphyria cutanea tarda. Other conditions manifest microscopic acantholysis within the surface epithelium but are not associated with clinical bullae, such as Darier disease and Grover disease. Finally, both infectious and non-infectious causes exist for the development of neutrophilic pustules in the epidermis, as seen in pustular psoriasis, Sneddon-Wilkinson disease (subcorneal pustular dermatosis), and acute generalized exanthematous pustulosis. This review considers the clinical and histological features of all of these diseases.

Immunohistochemistry and Polymerase Chain Reaction for Detection Human Papilloma Virus in Warts: A Comparative Study

Background

Immunohistochemistry and polymerase chain reaction (PCR) are the most widely used methods for the detection of viruses. PCR is known to be a more sensitive and specific method than the immunohistochemical method at this time, but PCR has the disadvantages of high cost and skilled work to use widely. With the progress of technology, the immunohistochemical methods used in these days has come to be highly sensitive and actively used in the diagnostic fields.

Objective

To evaluate and compare the usefulness of immunohistochemistry and PCR for detection human papilloma virus (HPV) in wart lesions.

Methods

Nine biopsy samples of verruca vulgaris and 10 of condyloma accuminatum were examined. Immunohistochemical staining using monoclonal antibody to HPV L1 capsid protein and PCR were done for the samples. DNA sequencing of the PCR products and HPV genotyping were also done.

Results

HPV detection rate was 78.9% (88.9% in verruca vulgaris, 70.0% in condyloma accuminatum) on immunohistochemistry and 100.0% for PCR. HPV-6 genotype showed a lower positivity rate on immunohistochemistry (50.0%) as compared to that of the other HPV genotypes.

Conclusion

Immunohistochemistry for HPV L1 capsid protein showed comparable sensitivity for detection HPV. Considering the high cost and great effort needed for the PCR methods, we can use immunohistochemistry for HPV L1 capsid protein with the advantage of lower cost and simple methods for HPV detection.