Not all that glitters is COVID-19: a case series demonstrating the need for histopathology when skin findings accompany SARS-CoV-2 infection

Characterization and Management of Amicrobial Pustulosis of the Folds, Aseptic Abscess Syndrome, Behçet Disease, Neutrophilic Eccrine Hidradenitis, and Pyostomatitis Vegetans-Pyodermatitis Vegetans

Neutrophilic dermatoses are a broadly heterogeneous group of inflammatory skin disorders. This article reviews 5 conditions: amicrobial pustulosis of the folds, aseptic abscess syndrome, Behçet disease, neutrophilic eccrine hidradenitis, and pyostomatitis vegetans-pyodermatitis vegetans.The authors include up-to-date information about their epidemiology, pathogenesis, clinicopathologic features, diagnosis, and management.

A Series of 69 COVID-related Dermatoses With Biopsy, Immunohistochemistry With Anti-spike 3, in situ Hybridization and PCR: A Critical Reappraisal of Viral Involvement in COVID-19 Skin Lesions

BACKGROUND

Despite the large number of articles published on skin lesions related to COVID-19, clinicopathological correlation has not been performed consistently and immunohistochemistry to demonstrate spike 3 protein expression has not been validated through RT-PCR.

MATERIAL AND METHODS

We compiled 69 cases of patients with confirmed COVID-19, where skin lesions were clinically and histopathologically studied. Immunohistochemistry (IHC) and RT-PCR was performed in skin biopsies.

RESULTS

After a careful review of the cases, 15 were found to be dermatosis not related to COVID-19, while the rest of the lesions could be classified according to their clinical characteristics as vesicular (4), maculopapular eruptions (41), urticariform (9), livedo and necrosis (10) and pernio-like (5). Although histopathological features were similar to previously reported results, we found two previously unreported findings, maculopapular eruptions with squamous eccrine syringometaplasia and neutrophilic epitheliotropism. IHC showed in some cases endothelial and epidermal staining but RT-PCR was negative in all the tested cases. Thus, direct viral involvement could not be demonstrated.

CONCLUSIONS

Despite presenting the largest series of confirmed COVID-19 patients with histopathologically studied skin manifestations, direct viral involvement was difficult to establish. Vasculopathic and urticariform lesions seem to be those more clearly related to the viral infection, despite IHC or RT-PCR negative results failed to demonstrate viral presence. These findings, as in other dermatological areas, highlight the need of a clinico-pathological correlation to increase knowledge about viral involvement in COVID-19 skin-related lesions.

A Series of 69 COVID-related Dermatoses With Biopsy, Immunohistochemistry With Anti-spike 3, in situ Hybridization and PCR: A Critical Reappraisal of Viral Involvement in COVID-19 Skin Lesions

BACKGROUND

Despite the large number of articles published on skin lesions related to COVID-19, clinicopathological correlation has not been performed consistently and immunohistochemistry to demonstrate spike 3 protein expression has not been validated through RT-PCR.

MATERIAL AND METHODS

We compiled 69 cases of patients with confirmed COVID-19, where skin lesions were clinically and histopathologically studied. Immunohistochemistry (IHC) and RT-PCR was performed in skin biopsies.

RESULTS

After a careful review of the cases, 15 were found to be dermatosis not related to COVID-19, while the rest of the lesions could be classified according to their clinical characteristics as vesicular (4), maculopapular eruptions (41), urticariform (9), livedo and necrosis (10) and pernio-like (5). Although histopathological features were similar to previously reported results, we found two previously unreported findings, maculopapular eruptions with squamous eccrine syringometaplasia and neutrophilic epitheliotropism. IHC showed in some cases endothelial and epidermal staining but RT-PCR was negative in all the tested cases. Thus, direct viral involvement could not be demonstrated.

CONCLUSIONS

Despite presenting the largest series of confirmed COVID-19 patients with histopathologically studied skin manifestations, direct viral involvement was difficult to establish. Vasculopathic and urticariform lesions seem to be those more clearly related to the viral infection, despite IHC or RT-PCR negative results failed to demonstrate viral presence. These findings, as in other dermatological areas, highlight the need of a clinico-pathological correlation to increase knowledge about viral involvement in COVID-19 skin-related lesions.

Neutrophilic eccrine hidradenitis: a retrospective study

BACKGROUND

Neutrophilic eccrine hidradenitis (NEH) is a benign neutrophilic dermatosis not well recognized beyond an association with malignancy. Although the disease is commonly reported in adults with malignancy, this association is uncommon in children. The diagnosis of NEH is predominantly based on histologic findings to exclude alternative diagnoses for adults, but biopsy is not usually required for children.

METHODS

A retrospective study was performed of adult and pediatric patients diagnosed with NEH at three Mayo Clinic sites from January 1, 1992, to January 1, 2022. The aim of this study was to elucidate risk factors for NEH and its clinical characteristics, treatment options, and natural course. Clinical information and pathologic results were collected from health records. Available pathologic slides were reviewed with a dermatopathologist.

RESULTS

Of 47 patients identified, 33 had either histologic or clinical confirmation of the diagnosis; 21 were adults (64%), and 12 were children (36%). Most adults (16/21; 76%) had underlying malignancy and received chemotherapy. Five adults (24%) were classified as having idiopathic NEH, and they were younger and had higher NEH recurrence rates than the other adults. Only one pediatric patient (8%) had underlying malignancy. For 10 children (83%), NEH was preceded by strenuous activity. Initial findings of idiopathic NEH were palmoplantar eruptions for both adult and pediatric patients, whereas malignancy-associated NEH commonly involved the face and axillae.

CONCLUSIONS

Among adults, NEH is commonly associated with malignancy and chemotherapy. Among children, idiopathic NEH occurs primarily after overexertion, and malignancy is highly unlikely to be the cause of NEH.

Malassezia Folliculitis in the Setting of COVID-19

Purpose of Review

To review recent literature on Malassezia folliculitis and explore its association with COVID-19.

Recent Findings

Reports of Malassezia folliculitis in the setting of COVID-19 are scarce. Shared characteristics between affected individuals include male sex, obesity, intensive care, and administration of systemic antibiotics and systemic steroids. Dexamethasone can potentially stimulate sebum production and therefore lead to Malassezia proliferation. The clinical picture of Malassezia folliculitis accompanying COVID-19 is similar to classic descriptions but tends to spare the face and predominates in occlusion sites.

Summary

Malassezia folliculitis is under-recognized. Fever, sweating, occlusion, immobility, antibiotics, and dexamethasone contribute to COVID-19 patients developing Malassezia folliculitis. Antifungal therapy, together with correcting predisposing factors, is the mainstay of management. Future research should explore the relationship between systemic steroids and other acneiform reactions.

SARS-CoV-2 Infection and Vaccination Cutaneous Manifestations for the Inpatient Dermatologist

Purpose of Review

The overall purpose of this review was to characterize and summarize cutaneous eruptions associated with coronavirus disease 2019 (COVID-19) as well as COVID-19 vaccination.

Recent Findings

Cutaneous eruptions associated with COVID-19 infection have a reported frequency of 1-20%. Increased COVID-19 disease severity has been associated with morbilliform exanthems, urticaria, retiform purpura, and livedo racemosa. Papulovesicular eruptions were associated with a milder COVID-19 disease course. A range of dermatoses have also been reported with COVID-19 vaccination but have rarely prevented subsequent vaccination.

Summary

Dermatologists should be aware of the associations between COVID-19 disease severity and cutaneous eruptions. Livedo racemosa and retiform purpura are particularly associated with increased disease severity and death. In the setting of COVID-19 vaccination, cutaneous eruptions can largely be managed symptomatically and very rarely do these reactions prevent subsequent vaccination.

Urticarial vasculitis: Clinical and laboratory findings with a particular emphasis on differential diagnosis

Urticarial vasculitis (UV) is a rare cutaneous vasculitis of small vessels characterized by recurrent episodes of wheal-like lesions that tend to last more than 24 hours, healing with a residual ecchymotic postinflammatory hyperpigmentation. The histopathologic pattern of UV is that of leukocytoclastic vasculitis, consisting of fibrinoid necrosis of dermal vessels' walls and neutrophil-rich perivascular inflammatory infiltrates. Although its etiopahogenesis remains still undefined, UV is now regarded as an immune complex-driven disease with activation of the complement cascade, leading to exaggerated production of anaphylatoxins that are responsible for neutrophil recruitment and activation. This condition can be categorized into 2 main entities according to serum complement levels: normocomplementemic UV and hypocomplementemic UV, the latter being associated with circulating anti-C1q autoantibodies and possible extracutaneous manifestations. Systemic multiorgan involvement may be seen particularly in syndromic hypocomplementemic UV, also known as McDuffie syndrome. This review summarizes the clinicopathological and laboratory features as well as the underlying pathophysiological mechanisms of UV. A focus on its main differential diagnoses is provided, that is, chronic spontaneous urticaria, bullous pemphigoid, IgA (Henoch-Schönlein purpura) and IgM/IgG immune complex vasculitis, lupus erythematous tumidus, Wells syndrome, erythema multiforme, cutaneous mastocytosis, cryopyrin-associated periodic syndromes, and coronavirus disease 2019-associated and anti-severe acute respiratory syndrome coronavirus 2-vaccine-associated urticarial eruptions.

Paucity of cutaneous manifestations of COVID-19 among inpatients in a referral hospital in India

Background

Varied cutaneous manifestations of COVID-19 have been described, but most studies are based on photographic or application-based observations, without a direct observed-based evaluation by dermatologists.

Objective

To study the types of cutaneous manifestations of COVID-19 among confirmed inpatients admitted to COVID-19 wards and intensive care units (ICUs).

Methods

This cross-sectional analysis was conducted at a referral hospital in Delhi, India. Four hundred forty consecutive reverse transcription-polymerase chain reaction (RT-PCR)–confirmed cases diagnosed with moderate or severe COVID-19 and admitted to COVID-19 wards or ICUs, respectively, were included. A cutaneous finding was considered to be associated with COVID-19 if it had been described earlier as a consequence of COVID-19 and was observed at the time of or within the first 48 hours of admission (after excluding drugs and comorbidities as causes).

Results

Two hundred seventy patients with moderate COVID-19 were admitted to COVID-19 wards, whereas 170 with severe disease were admitted to ICUs. Only 7 of the 270 ward patients (2.59%) and 3 of the 170 ICU patients (1.76%) had cutaneous findings associated with COVID-19.

Conclusion

Cutaneous findings attributable to COVID-19 are infrequent, and we believe that these might have been overestimated or overemphasized in earlier studies. Although coagulopathic findings may be associated with severe COVID-19, causation cannot be established in this cross-sectional study.

The crucial role of clinicopathological correlation in COVID-19-related cutaneous manifestations

Linked article: Barrera‐Godínez A et al. J Eur Acad Dermatol Venereol 2021; 35: 1865–1873. https://doi.org/10.1111/jdv.17381