Venous Thromboembolism in Hospitalized COVID-19 Patients Treated in a Single Academic Center in Mexico: A Case Series Study.

BACKGROUND: The increasing prevalence of venous thromboembolism (VTE) among patients with coronavirus disease 2019 (COVID-19) is a matter of concern as it contributes significantly to patients' morbidity and mortality. Data regarding the optimal anticoagulation regimen for VTE prevention and treatment remain scarce. This study describes the characteristics, treatment, and outcomes of COVID-19 patients with VTE treated in a single academic center in Mexico. METHODS: We conducted a retrospective study of all patients with a positive PCR test for SARS-CoV-2 hospitalized in a single academic center in Monterrey, Mexico, between March 2020 and February 2021, with a radiologically confirmed VTE, including deep venous thrombosis (DVT) and pulmonary embolism (PE). Informed consent was obtained from each patient before reviewing their medical records. RESULTS: Of the 2000 COVID-19 hospitalized patients, 36 (1.8%) developed VTE and were included in the analysis. The median age was 60 years (range 32-88 years), and up to 78% (n = 28) were males. Most patients (n = 34, 94%) had an underlying comorbidity and 47% (n = 17) had a BMI ≥ 30 kg/m2. In most cases (n=28, 78%), VTE presented as a PE, whereas the remaining 22% (n = 8) had a DVT. The median time between hospital admission and VTE was 8 days (range 0-33 days). Regarding the thromboprophylaxis regimen, 35/36 patients received low molecular weight heparin enoxaparin on admission, most commonly at a dose of 60 mg daily (n = 19, 53%). Other complications presented were superinfection (n = 19, 53%), acute kidney injury (n = 11, 31%), and septic shock (n = 5, 14%). A total of 69% of patients (n = 25) required intensive care unit admission, and patients' overall mortality was 55.6%. CONCLUSION: VTE remains a significant cause of increased morbidity and mortality among patients with COVID-19. The strikingly high mortality among patients with VTE highlights the need for further investigation regarding the best preventive, diagnostic, and treatment approaches.

Extensive deep vein thrombosis and pulmonary embolism as a unique clinical manifestation of COVID-19 in a young healthy patient.

BACKGROUND/OBJECTIVE: Deep vein thrombosis and pulmonary embolism have been described as complications in previously diagnosed COVID-19 patients, especially in those admitted in critical ill units, but, to our knowledge, there is no report of venous thromboembolism in an otherwise asymptomatic COVID-19 patient. METHODS: We report the case of a 22-year-old female, healthy patient with pulmonary embolism (Pulmonary Embolism Severity Index Score 22 points, low risk) and extensive proximal deep vein thrombosis as a unique clinical manifestation of the new coronavirus disease. RESULTS: The patient had no risk factors and no familial history of venous thromboembolism. All thrombophilia markers were negative. The patient was treated as first by an independent vascular team, performing vena cava filter placement and open thrombectomy. Her symptoms worsened, and after 3 weeks, she underwent US-enhanced thrombolysis and mechanical thrombectomy. She was isolated for 10 days and did not develop any other clinical manifestation of COVID-19 disease. During follow-up, she remained asymptomatic and complete patency of the venous system was achieved. Full oral anticoagulation was conducted for 6 months. CONCLUSION: COVID-19 appears to be a multi-symptomatic disease, and venous thromboembolism without any other previous described COVID-19 symptom could be considered one of its diverse clinical presentations and RT-PCR for SARS-CoV-2 tests emerge to be mandatory in patients with otherwise unexpected venous thrombosis.

Severe Acute Respiratory Syndrome Coronavirus 2 Impact on the Central Nervous System: Are Astrocytes and Microglia Main Players or Merely Bystanders?

With confirmed coronavirus disease 2019 (COVID-19) cases surpassing the 18 million mark around the globe, there is an imperative need to gain comprehensive understanding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although the main clinical manifestations of COVID-19 are associated with respiratory or intestinal symptoms, reports of neurological signs and symptoms are increasing. The etiology of these neurological manifestations remains obscure, and probably involves several direct pathways, not excluding the direct entry of the virus to the central nervous system (CNS) through the olfactory epithelium, circumventricular organs, or disrupted blood-brain barrier. Furthermore, neuroinflammation might occur in response to the strong systemic cytokine storm described for COVID-19, or due to dysregulation of the CNS rennin-angiotensin system. Descriptions of neurological manifestations in patients in the previous coronavirus (CoV) outbreaks have been numerous for the SARS-CoV and lesser for Middle East respiratory syndrome coronavirus (MERS-CoV). Strong evidence from patients and experimental models suggests that some human variants of CoV have the ability to reach the CNS and that neurons, astrocytes, and/or microglia can be target cells for CoV. A growing body of evidence shows that astrocytes and microglia have a major role in neuroinflammation, responding to local CNS inflammation and/or to disbalanced peripheral inflammation. This is another potential mechanism for SARS-CoV-2 damage to the CNS. In this comprehensive review, we will summarize the known neurological manifestations of SARS-CoV-2, SARS-CoV and MERS-CoV; explore the potential role for astrocytes and microglia in the infection and neuroinflammation; and compare them with the previously described human and animal CoV that showed neurotropism to propose possible underlying mechanisms.