The inflammasome complex is a key part of chronic diseases and acute infections, being responsible for cytokine release and cell death mechanism regulation. The SARS-CoV-2 infection is characterized by a dysregulated cytokine release. In this context, the inflammasome complex analysis within SARS-CoV-2 infection may prove beneficial to understand the disease’s mechanisms. Post-mortem minimally invasive autopsies were performed in patients who died from COVID-19 (n = 24), and lung samples were compared to a patient control group (n = 11) and an Influenza A virus H1N1 subtype group from the 2009 pandemics (n = 10). Histological analysis was performed using hematoxylin-eosin staining. Immunohistochemical (IHC) staining was performed using monoclonal antibodies against targets: ACE2, TLR4, NF-κB, NLRP-3 (or NALP), IL-1β, IL-18, ASC, CASP1, CASP9, GSDMD, NOX4, TNF-α. Data obtained from digital analysis underwent appropriate statistical tests. IHC analysis showed biomarkers that indicate inflammasome activation (ACE2; NF-κB; NOX4; ASC) were significantly increased in the COVID-19 group (p < 0.05 for all) and biomarkers that indicate cell pyroptosis and inflammasome derived cytokines such as IL-18 (p < 0.005) and CASP1 were greatly increased (p < 0.0001) even when compared to the H1N1 group. We propose that the SARS-CoV-2 pathogenesis is connected to the inflammasome complex activation. Further studies are still warranted to elucidate the pathophysiology of the disease.

Background During the COVID-19 pandemic, healthcare services reduced the number of elective procedures performed. Vascular surgery patients are a group at risk of contracting severe forms of the infection, but are also susceptible to complications of their underlying diseases if they do not receive routine care. It is therefore necessary to understand the direct and indirect impacts and consequences of the pandemic on vascular patients. Objectives To assess the impact of 1 year of the pandemic on a vascular surgery service and changes to the profile of surgeries during the same period. Methods An analysis was conducted of the medical records of patients who underwent elective and emergency surgery from 2019 to 2021. A review of the literature was also conducted, using the search terms “vascular surgery”, “COVID-19”, and “amputations”. Data were analyzed with Stata/SE v.14.1 (StataCorpLP, United States). Results A total of 1,043 surgeries were identified during the study period, 51.6% conducted pre-pandemic and 48.4% performed during the pandemic. There was a reduction in the number of elective surgeries and an increase in the number of lower limb amputations and surgical debridements. Increases were also observed in the proportion of patients with peripheral arterial occlusive disease with advanced Rutherford classifications and in the number of cases of diabetic foot. Conclusions The reduction in elective care and patients’ reluctance to seek health services during the pandemic are the probable causes of increased severity of patient status, with greater need for lower limb amputation and surgical debridement and changes to the profile of the surgery performed at the service.

Resumo Os leiomiossarcomas de veia cava inferior são tumores raros, que representam menos de 0,7% de todos os leiomiossarcomas retroperitoneais. Eles são mais comuns em mulheres e causam quadros inespecíficos de dor abdominal crônica. Neste relato, apresentamos um caso de paciente do sexo feminino, de 53 anos de idade, com queixa de dor abdominal crônica periumbilical inespecífica com evolução há 8 meses, diagnosticada com leiomiossarcoma de veia cava inferior por angiotomografia computadorizada. A paciente foi tratada com ressecção completa do tumor e reconstrução da veia cava inferior, com interposição de prótese de dácron. O tratamento considerado padrão-ouro consiste na excisão cirúrgica completa, visto que esses tumores são resistentes a quimioterapia e radioterapia. O prognóstico desses pacientes está intimamente relacionado com a precocidade do diagnóstico, e, por isso, é de grande relevância o conhecimento dessa doença como diagnóstico diferencial de dor abdominal crônica e inespecífica por cirurgiões vasculares e cirurgiões gerais.

Inferior vena cava leiomyosarcomas are rare tumors that account for less than 0.7% of all retroperitoneal leiomyosarcomas. They are more common in women and cause nonspecific chronic abdominal pain. In this report, we present the case of a 53-year-old female patient complaining of chronic nonspecific periumbilical abdominal pain with initial onset 8 months previously who was diagnosed with inferior vena cava leiomyosarcoma by computed tomography angiography. The patient was treated with complete resection of the tumor and reconstruction of the inferior vena cava with interposition of a Dacron prosthetic graft. The treatment considered the gold standard consists of complete surgical excision, because these tumors are resistant to chemotherapy and radiotherapy. The prognosis of these patients is closely related to early diagnosis. Therefore, it is very important that vascular and general surgeons know that this disease is a possible differential diagnosis of chronic abdominal pains.

Obesity has been identified as an independent risk factor for severe COVID-19 unfavorable outcomes. Several factors, such as increased ACE2 receptor expression and chronic inflammation, can contribute to this relationship, yet the activation of the NLRP3 inflammasome pathway is also a key element. Our primary goal was to determine whether chronic NLRP3 inflammasome activation in people with obesity is different in critical COVID-19 and in critical chronic conditions. A retrospective analysis was conducted using clinical data and post-mortem lung tissue samples from 14 COVID-19 patients with obesity (group A) and 9 patients with obesity who died from non-COVID-19 causes (group B). Immunohistochemical analysis assessed twelve markers related to the NLRP3 inflammasome pathway. Group A showed a significantly higher expression of ASC (p = 0.0387) and CASP-1 (p = 0.0142). No significant differences were found for IL-8, TNF-α, NF-kB, NLRP3, IL-1β, and gasdermin-D. Group B had higher levels of IL-6 (p < 0.0001), IL-18 (p = 0.002), CASP-9 (p < 0.0001), and HIF (p = 0.0327). We concluded that COVID-19 activates the NLRP3 inflammasome pathway, possibly leading to pyroptotic cell death mediated by caspase-1. In contrast, people with obesity without COVID-19, despite exhibiting some markers of the NLRP3 inflammasome, are more likely to experience necroptosis mediated by caspase-9.