No abstract

Pediatric PG has a more varied anatomic distribution and a greater predominance of pustular lesions than PG in adults and a strong association with inflammatory bowel disease.

Pernio or chilblains is characterized by erythema and swelling at acral sites (eg, toes and fingers), typically triggered by cold exposure. Clinical and histopathologic features of pernio are well described, but the pathogenesis is not entirely understood; vasospasm and a type I interferon (IFN-I) immune response are likely involved. During the coronavirus disease 2019 (COVID-19) pandemic, dermatologists have observed an increase in pernio-like acral eruptions. Direct causality of pernio due to COVID-19 has not been established in many cases because of inconsistent testing methods (often negative results) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, a form of COVID-19-associated pernio (also called COVID toes) is probable because of increased occurrence, frequently in young patients with no cold exposure or a history of pernio, and reports of skin biopsies with positive SARS-CoV-2 immunohistochemistry. PubMed was searched between January 1, 2020, and December 31, 2020 for publications using the following keywords: pernio, chilblain, and acral COVID-19. On the basis of our review of the published literature, we speculate that several unifying cutaneous and systemic mechanisms may explain COVID-19-associated pernio: (1) SARS-CoV-2 cell infection occurs through the cellular receptor angiotensin-converting enzyme 2 mediated by transmembrane protease serine 2, subsequently affecting the renin-angiotensin-aldosterone system with an increase in the vasoconstricting, pro-inflammatory, and prothrombotic angiotensin II pathway. (2) Severe acute respiratory syndrome coronavirus 2 cell infection triggers an immune response with robust IFN-I release in patients predisposed to COVID-19-associated pernio. (3) Age and sex discrepancies correlated with COVID-19 severity and manifestations, including pernio as a sign of mild disease, are likely explained by age-related immune and vascular differences influenced by sex hormones and genetics, which affect susceptibility to viral cellular infection, the renin-angiotensin-aldosterone system balance, and the IFN-I response.

Background/Aims: Pernio (chilblains) is an inflammatory condition classically characterized by localized erythema and swelling of acral sites upon exposure to cool and damp conditions. We sought to determine whether cold-induced vasospasm has a role in the development of pernio. Methods: We retrospectively reviewed 5 patients with pernio who were seen at our institution between January 1, 2000 and December 31, 2011, and had undergone a noninvasive arterial vascular study of the upper extremities that corresponded to a site of clinical involvement of pernio and who had also undergone vasospastic testing and ice water immersion as part of the noninvasive arterial vascular study protocol. Results: Vascular testing in all patients (mean age 37.8 years; 4 women) demonstrated vasospasm with ice water immersion. Conclusion: Our findings suggest that vasospasm likely has a role in the pathophysiology of pernio and may also provide a rationale for the pharmacological treatment of vasospasm in patients with pernio.

In the properly selected patient and anatomic location, CTL taken as the first stage in MMS can be an effective and time-saving technique, leaving wounds in optimal condition for granulation with a low complication rate. Tissue sparing may allow for more reconstructive options.