COVID-19: Time for a clinical classification?

COVID-19 pandemic caused by SARS-CoV-2 virus has been around for 2 years causing significant health-care catastrophes in most parts of the world. The understanding of COVID-19 continues to expand, with multiple newer developments such as the presence of asymptomatic cases, feco-oral transmission, and endothelial dysfunction. The existing classification was developed before this current understanding. With the availability of recent literature evidences, we have attempted a classification encompassing pathogenesis and clinical features for better understanding of the disease process. The pathogenesis of COVID-19 continues to evolve. The spiked protein of the SARS-CoV-2 virus binds to ACE2 receptors causes direct cytopathic damage and hyperinflammatory injury. In addition to alveolar cells, ACE2 is also distributed in gastrointestinal tract and vascular endothelium. ACE2-SARS-CoV-2 interaction engulfs the receptors leading to depletion. Accumulation of Ang2 via AT1 receptor (AT1R) binding causes upregulation of macrophage activity leading to pro-inflammatory cytokine release. Interleukin-6 (IL-6) has been attributed to cause hyperinflammatory syndrome in COVID-19. In addition, it also causes severe widespread endothelial injury through soluble IL-6 receptors. Thrombotic complications occur following the cleavage and activation of von Willebrand factor. Based on the above understanding, clinical features, organ involvement, risk stratification, and disease severity, we have classified COVID-19 patients into asymptomatic, pulmonary, GI, and systemic COVID-19 (S-COVID-19). Studies show that the infectivity and prognosis are different and distinct amongst these groups. Systemic-COVID-19 patients are more likely to be critically ill with multi-organ dysfunction and thrombo-embolic complications.

Outcome of Patients Waitlisted for Deceased Donor Liver Transplantation During COVID-19 Pandemic: A Single-Center Experience.

Background and aim: COVID-19 pandemic has strained several healthcare resources across the world. While liver transplantation (LT) is the only curative therapy for patients with end-stage liver disease, we aimed to determine the clinical outcome of patients waitlisted for deceased donor liver transplantation (DDLT) during COVID-19 pandemic. Methods: A retrospective comparative observational study of adult patients waitlisted for DDLT from January 2019 to January 2022 at our liver unit (Dr Rela Institute and Medical Center, Chennai, Tamil Nadu, India) was carried out. Patient demographics, disease etiology, Model for End-Stage Liver Disease - Sodium (MELD-Na) score were calculated for all patients listed during the study period. Clinical event was defined as number of DDLT, death in the absence of transplant, and patients awaiting LT were compared. Statistical analysis was performed with SPSS V24.0. Results: In total, 310 patients were waitlisted for DDLT, of whom 148, 63, and 99 patients listed during 2019, 2020, and 2021 (till January 2022), respectively; 22 (53.6%), 10 (24.3%), and 9 (21.9%) patients underwent DDLT in the year 2019, 2020, and 2021 (P = 0.000); 137 patients (44.19%) died on the DDLT waitlist of whom 41 (29.9%), 67 (48.9%), and 29 (21.1%) in the year 2019, 2020, and 2021 (P = 0.000), respectively. Waitlist mortality was significantly higher during the COVID first wave. Conclusion: COVID-19 pandemic has significantly impacted patients waitlisted for DDLT in India. With limited access to healthcare facilities and decreased organ donation rates during the pandemic, there was a considerable reduction in the patients waitlisted for DDLT, lesser number of patients underwent DDLT, and higher waitlist mortality during the pandemic year. Efforts to improve organ donation in India should be strongly implemented.