Understanding the Elevated Lethality of COVID-19 in Liver Transplant Recipients: Does Immunosuppression Management Matter? Results from a Brazilian Multicentric Historical Cohort.

BACKGROUND: Infections by SARS-CoV-2 in liver transplant recipients (LT) patients are of particular concern, notably due to perceived added risks related to immunosuppression and comorbidity burden. Current literature on this topic often relies on small, non-standardized, and geographically limited studies. This manuscript describes COVID-19 presentations and causes for elevated mortality in a large cohort of LT recipients. METHODS: This study was designed as a multicentric historical cohort, including LT recipient patients with COVID-19 in 25 study centers, with the primary endpoint being COVID-related death. We also collected demographic, clinical, and laboratory data regarding presentation and disease progression. RESULTS: Two hundred and thirty-four cases were included. The study population was predominantly male and White and had a median age of 60 years. The median time from transplantation was 2.6 years (IQR 1-6). Most patients had at least one comorbidity (189, 80.8%). Patient age (P = .04), dyspnea (P < .001), intensive care unit admission (P < .001), and mechanical ventilation (P < .001) were associated with increased mortality. Modifications of immunosuppressive therapy (P < .001), specifically the suspension of tacrolimus, maintained significance in multivariable analysis. CONCLUSIONS: Attention to risk factors and the individualization of patient care, especially regarding immunosuppression management, is crucial for delivering more precise interventions to these individuals.

Antimicrobial oral lavage reduces the SARS-CoV-2 load in intubated patients: randomized clinical trial

Background The oral cavity can be a reservoir for SARS-CoV-2 and may play a crucial role in the viral transmission in the hospital environment. Objective To investigate whether an oral hygiene protocol with chlorhexidine (CHX) used alone and in combination with hydrogen peroxide (HP) in the intensive care unit was effective in reducing the SARS-CoV-2 viral load in the oral cavity. Methods SARS-CoV-2 viral load was measured on oral fluid samples collected from patients undergoing orotracheal intubation. The study sample was randomly in: CHX group (n = 19) - oral rinse using only 0.12% CHX solution;HP+CHX group (n = 24) - oral rinse with 1.5% HP and 0.12% CHX. The samples were collected before the interventions (T0), immediately (T1), 30 minutes (T2) and 60 minutes (T3) after the procedure. Results A significant viral load reduction was observed at T1 (mean ± SD:–0.57 ± 0.19 log10;–73.2%;p = 0.022) in the HP+CHX group. No statistically significant differences between any time points were observed in the CHX group. Conclusion The HP+CHX oral rinses significantly reduced the SARS-CoV-2 viral load in the oral fluid immediately after the procedure. The CHX oral rinse alone did not result in any significant viral load reductions.

Antimicrobial oral lavage reduces the SARS-CoV-2 load in intubated patients: randomized clinical trial.

Background: The oral cavity can be a reservoir for SARS-CoV-2 and may play a crucial role in the viral transmission in the hospital environment. Objective: To investigate whether an oral hygiene protocol with chlorhexidine (CHX) used alone and in combination with hydrogen peroxide (HP) in the intensive care unit was effective in reducing the SARS-CoV-2 viral load in the oral cavity. Methods: SARS-CoV-2 viral load was measured on oral fluid samples collected from patients undergoing orotracheal intubation. The study sample was randomly in: CHX group (n = 19) - oral rinse using only 0.12% CHX solution; HP+CHX group (n = 24) - oral rinse with 1.5% HP and 0.12% CHX. The samples were collected before the interventions (T0), immediately (T1), 30 minutes (T2) and 60 minutes (T3) after the procedure. Results: A significant viral load reduction was observed at T1 (mean ± SD:-0.57 ± 0.19 log10;-73.2%;p = 0.022) in the HP+CHX group. No statistically significant differences between any time points were observed in the CHX group. Conclusion: The HP+CHX oral rinses significantly reduced the SARS-CoV-2 viral load in the oral fluid immediately after the procedure. The CHX oral rinse alone did not result in any significant viral load reductions.

A Machine Learning Model for Predicting Hospitalization in Patients with Respiratory Symptoms during the COVID-19 Pandemic.

A machine learning approach is a useful tool for risk-stratifying patients with respiratory symptoms during the COVID-19 pandemic, as it is still evolving. We aimed to verify the predictive capacity of a gradient boosting decision trees (XGboost) algorithm to select the most important predictors including clinical and demographic parameters in patients who sought medical support due to respiratory signs and symptoms (RAPID RISK COVID-19). A total of 7336 patients were enrolled in the study, including 6596 patients that did not require hospitalization and 740 that required hospitalization. We identified that patients with respiratory signs and symptoms, in particular, lower oxyhemoglobin saturation by pulse oximetry (SpO2) and higher respiratory rate, fever, higher heart rate, and lower levels of blood pressure, associated with age, male sex, and the underlying conditions of diabetes mellitus and hypertension, required hospitalization more often. The predictive model yielded a ROC curve with an area under the curve (AUC) of 0.9181 (95% CI, 0.9001 to 0.9361). In conclusion, our model had a high discriminatory value which enabled the identification of a clinical and demographic profile predictive, preventive, and personalized of COVID-19 severity symptoms.

COVID-19: angiotensin-converting enzyme 2 (ACE2) expression and tissue susceptibility to SARS-CoV-2 infection.

COVID-19 pandemic is caused by the novel coronavirus SARS-CoV-2. Angiotensin-converting enzyme 2 (ACE2) is not only an enzyme but also a functional receptor on cell surfaces through which SARS-CoV-2 enters the host cells and is highly expressed in the heart, kidneys, and lungs and shed into the plasma. ACE2 is a key regulator of the renin-angiotensin-aldosterone system (RAAS). SARS-CoV-2 causes ACE/ACE2 balance disruption and RAAS activation, which leads ultimately to COVID-19 progression, especially in patients with comorbidities, such as hypertension, diabetes mellitus, and cardiovascular disease. Therefore, ACE2 expression may have paradoxical effects, aiding SARS-CoV-2 pathogenicity, yet conversely limiting viral infection. This article reviews the existing literature and knowledge of ACE2 in COVID-19 setting and focuses on its pathophysiologic involvement in disease progression, clinical outcomes, and therapeutic potential.