Chilblains observed during the COVID-19 pandemic cannot be distinguished from classic, cold-related chilblains

Background: Type 1 interferon (IFN-I) response induced by SARS-CoV-2 has been hypothesized to explain the association between chilblain lesions (CL) and SARS-CoV-2 infection. Objective: To explore direct cytopathogenicity of SARS-CoV-2 in CL and to focus on IFN-I expression in patients with chilblains. Materials & Methods: A monocentric cohort of 43 patients presenting with CL from April 2020 to May 2021 were included. During this period, all CL were, a priori, considered to be SARS-CoV-2-related. RT-qPCR on nasopharyngeal swabs and measurements of anti-SARS-CoV-2 antibodies were performed. Anti-SARS-CoV-2 immunostainings as well as SARS-CoV-2 RT-qPCR were performed on biopsy specimens of CL and controls. Expression of MX1 and IRF7 was analysed on patients' biopsy specimens and/or PBMC and compared with controls and/or chilblains observed before the pandemic. Serum IFN-α was also measured. Results: RT-qPCR was negative in all patients and serological tests were positive in 11 patients. Immunostaining targeting viral proteins confirmed the lack of specificity. SARS-CoV-2 RNA remained undetected in all CL specimens. MX1 immunostaining was positive in CL and in pre-pandemic chilblains compared to controls. MX1 and IRF7 expression was significantly increased in CL specimens but not in PBMC. Serum IFN-α was undetected in CL patients. Conclusion: CL observed during the pandemic do not appear to be directly related to SARS-CoV-2 infection, either based on viral cytopathogenicity or high IFN-I response induced by the virus.

Evaluation of Chilblains as a Manifestation of the COVID-19 Pandemic.

Importance: During the coronavirus disease 2019 (COVID-19) pandemic, several cases of chilblains have been reported. Objective: To determine if chilblains are associated with COVID-19. Design, Setting, and Participants: This monocentric case series was conducted at the Department of Dermatology at Cliniques universitaires Saint-Luc, a tertiary care hospital in Brussels, Belgium, between April 10 and April 17, 2020. We evaluated a total of 31 referred patients who had recently developed chilblains. Main Outcomes and Measures: Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) was used to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA on nasopharyngeal swabs for all patients and in skin biopsy specimens for 22 patients. Blood samples from all patients were tested for specific anti-SARS-CoV-2 immunoglobulin (Ig) M and IgG antibodies. All patients had extended blood analyses. Histologic (22 patients) and immunofluorescence examinations (15 patients) were performed on the skin biopsy specimens. Results: The 31 patients were generally in good health; most were teenagers or young adults, and 19 were women. Histopathologic analysis of skin biopsy specimens (22 patients) confirmed the diagnosis of chilblains and showed occasional lymphocytic or microthrombotic phenomena. Immunofluorescence analyses showed vasculitis of small-diameter vessels in 7 patients. In all patients, SARS-CoV-2 RNA remained undetected by RT-PCR on nasopharyngeal swabs and in biopsy samples of the skin lesions. The IgM and IgG antibody titers were negative for SARS-CoV-2 in all patients (<1.0 arbitrary unit/mL). No significant abnormalities in blood test results were suggestive of systemic disease. Antinuclear antibody titers were low in 7 patients and higher in 1 patient. Conclusions and Relevance: Chilblains appeared not to be directly associated with COVID-19 in this case series. Lifestyle changes associated with community containment and lockdown measures are a possible explanation for these lesions.

Linear IgA dermatosis in association with angioimmunoblastic T-cell lymphoma infiltrating the skin: A case report with literature review.

Angioimmunoblastic T-cell lymphoma (AITL) is an aggressive form of peripheral T-cell lymphoma, characterized by systemic symptoms, diffuse lymphadenopathy, hepatosplenomegaly and immunodysregulation. Half of AITL is associated with cutaneous symptoms, but only few cases with bullous eruption have been described. Association with a linear IgA dermatosis is extremely rare. Linear IgA dermatosis can be idiopathic, or linked with drug intake or neoplastic disorders. Some cases of linear IgA dermatosis presenting as toxic epidermal necrolysis (TEN) have been described, most of them being drug induced. We here present the case of a 72-year-old man recently diagnosed with AITL who developed a bullous eruption, presenting as TEN. Histopathology showed deep cutaneous involvement of the lymphoma with a sub-epidermal blistering and direct immunofluorescence revealed a heavy IgA linear deposit on the dermal-epidermal junction. A diagnosis of linear IgA dermatosis associated with cutaneous involvement of an angioimmunoblastic T-cell lymphoma was made. Chemotherapy and corticosteroids allowed cutaneous improvement but the patient died of his lymphoma shortly after.

Primary cutaneous CD8+ and CD30+ T-cell lymphoproliferative disorders: case reports and clinical implications.

BACKGROUND: CD8+ CD30+ primary cutaneous T-cell lymphomas (PCTCL) are rare entities with overlapping pathological features and variable outcome. OBJECTIVES: We sought to highlight the importance of correlation between pathological findings and clinical presentation for correct classification of the disease. MATERIALS & METHODS: Two cases of CD8+ CD30+ PCTCL were investigated. The first patient presented with a multiple necro-erythematous lesion of the limb and the second with a papulo-necrotic lesion of the eyelid. RESULTS: Despite a different clinical presentation, pathological findings were similar in both cases. Clinico-pathological correlation led to a diagnosis of primary cutaneous CD8+ aggressive epidermotropic cytotoxic T-cell lymphoma in the first case and primary cutaneous anaplastic large-cell lymphoma in the second. The first patient died shortly after diagnosis and the second is alive without recurrence. CONCLUSIONS: Clinico-pathological correlation is essential for the correct identification of these rare diseases.

CD30+ Cutaneous Anaplastic Large-Cell Lymphoma of the Upper Eyelid: A Case Report.

CD30+ cutaneous anaplastic large-cell lymphoma is part of the CD30+ T-cell lymphoproliferative disorders. This type of lymphoma is in most cases indolent, with a high survival rate. We report the case of a 59-year-old patient with a 1-month lasting crusty lesion of the upper eyelid. Eyelid involvement is very uncommon, as the most frequent locations are the trunk and the limbs.

Characterization of the T cell response in allergic contact dermatitis caused by corticosteroids.

BACKGROUND: Delayed allergic hypersensitivity reactions have classically been described as type IV reactions, which are caused by T cells; however, the respective roles of CD4(+) and CD8(+) cells are yet to be defined. A central role for CD8(+) cytotoxic T cells as effector cells has been suggested. OBJECTIVES: To determine the type of T cell involved in corticosteroid allergy. METHODS: We analysed the kinetics of T cell recruitment and the cytokine production profile in positive patch tests of 27 corticosteroid-sensitized patients, as compared with control sites and control subjects. Skin biopsies, collected at 8, 24 and 48 hr following drug application, were embedded in paraffin for histological and immunohistological staining, and, in some cases, also deep-frozen for gene expression analyses. RESULTS: CD3(+) T cells were rapidly recruited in concert with the positivity of the patch test sites. High levels of interleukin (IL)-4, IL-5 and, to a lesser extent, interferon-γ suggested that both Th2 and Th1 cytokines were implicated. IL-4 was also produced by γδ T cell receptor (TCR) lymphocytes. CONCLUSIONS: This study showed that, in allergic contact dermatitis caused by corticosteroids, the inflammatory infiltrate is composed of CD3(+) T cells with a predominant Th2 cytokine profile, among which IL-4 is also produced by γδ TCR lymphocytes.