SARS-CoV-2 Omicron detection by antigen tests using saliva.

The Omicron emerged in November 2021 and became the predominant SARS-CoV-2 variant globally. It spreads more rapidly than ancestral lineages and its rapid detection is critical for the prevention of disease outbreaks. Antigen tests such as immunochromatographic assay (ICA) and chemiluminescent enzyme immunoassay (CLEIA) yield results more quickly than standard polymerase chain reaction (PCR). However, their utility for the detection of the Omicron variant remains unclear. We herein evaluated the performance of ICA and CLEIA in saliva from 51 patients with Omicron and 60 PCR negative individuals. The sensitivity and specificity of CLEIA were 98.0% (95%CI: 89.6-100.0%) and 100.0% (95%CI: 94.0-100.0%), respectively, with fine correlation with cycle threshold (Ct) values. The sensitivity and specificity of ICA were 58.8% (95%CI: 44.2-72.4%) and 100.0% (95%CI: 94.0-100.0%), respectively. The sensitivity of ICA was 100.0% (95%CI: 80.5-100.0%) when PCR Ct was less than 25. The Omicron can be efficiently detected in saliva by CLEIA. ICA also detects high viral load Omicron using saliva.

Post-COVID-19 Cholestasis: A Case Series and Review of Literature.

Background: Coronavirus disease-2019 (COVID-19) cholangiopathy is a recently known entity. There are very few reports of liver transplantation (LT) for COVID-19-induced cholangiopathy. It is well known that vaccines can prevent severe disease and improve outcomes. However, there are no reports on the impact of COVID-19 vaccines on cholestasis. Therefore, we aimed to compare the course and outcome of patients who developed cholestasis following COVID-19 infection among vaccinated and unvaccinated individuals. Methods: Patients diagnosed with post-COVID cholestasis during the pandemic were included in the study after excluding other causes of cholestasis. Results: Eight unvaccinated and seven vaccinated individuals developed cholestasis following COVID-19 infection. Baseline demographics, presentation, severity, and management of COVID-19 were similar in both groups. However, patients in the unvaccinated group had a protracted course. The peak ALP was 312 (239-517) U/L in the vaccinated group and 571.5 (368-1058) U/L in the unvaccinated group (P = 0.02). Similarly, the peak γ-glutamyl transpeptidase values were lower in the vaccinated (325 [237-600] U/L) than in the unvaccinated group (832 [491-1640] U/L; P = 0.004). However, the peak values of total bilirubin, transaminases, and INR were similar in both groups. Five patients developed ascites gradually in the unvaccinated group whereas none in the vaccinated group developed ascites. Plasma exchange was done in five patients, and two were successfully bridged to living donor LT in the unvaccinated group. Only two patients recovered with conservative management in the unvaccinated group, whereas all recovered with conservative management in the vaccinated group. The other four patients in the unvaccinated group were planned for LT. Conclusion: Post-COVID-19 cholestasis is associated with high morbidity and mortality, meriting early identification and appropriate management. Vaccination can modify the course of severe COVID-19 infection and improve outcomes.

Kombucha - An ancient fermented beverage with desired bioactivities: A narrowed review.

Kombucha, originated in China 2000  years ago, is a sour and sweet-tasted drink, prepared traditionally through fermentation of black tea. During the fermentation of kombucha, consisting of mainly acidic compounds, microorganisms, and a tiny amount of alcohol, a biofilm called SCOBY forms. The bacteria in kombucha has been generally identified as Acetobacteraceae. Kombucha is a noteworthy source of B complex vitamins, polyphenols, and organic acids (mainly acetic acid). Nowadays, kombucha is tended to be prepared with some other plant species, which, therefore, lead to variations in its composition. Pre-clinical studies conducted on kombucha revealed that it has desired bioactivities such as antimicrobial, antioxidant, hepatoprotective, anti-hypercholestorelomic, anticancer, anti-inflammatory, etc. Only a few clinical studies have been also reported. In the current review, we aimed to overhaul pre-clinical bioactivities reported on kombucha as well as its brief compositional chemistry. The literature data indicate that kombucha has valuable biological effects on human health.

Current state of diagnostic, screening and surveillance testing methods for COVID-19 from an analytical chemistry point of view.

Since December 2019, we have been in the battlefield with a new threat to the humanity known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this review, we describe the four main methods used for diagnosis, screening and/or surveillance of SARS-CoV-2: Real-time reverse transcription polymerase chain reaction (RT-PCR); chest computed tomography (CT); and different complementary alternatives developed in order to obtain rapid results, antigen and antibody detection. All of them compare the highlighting advantages and disadvantages from an analytical point of view. The gold standard method in terms of sensitivity and specificity is the RT-PCR. The different modifications propose to make it more rapid and applicable at point of care (POC) are also presented and discussed. CT images are limited to central hospitals. However, being combined with RT-PCR is the most robust and accurate way to confirm COVID-19 infection. Antibody tests, although unable to provide reliable results on the status of the infection, are suitable for carrying out maximum screening of the population in order to know the immune capacity. More recently, antigen tests, less sensitive than RT-PCR, have been authorized to determine in a quicker way whether the patient is infected at the time of analysis and without the need of specific instruments.

Effect of COVID-19 on Pre-existing Liver disease: What Hepatologist Should Know?

COVID-19 is characterized by predominant respiratory and gastrointestinal symptoms. Liver enzymes derangement is seen in 15-55% of the patients. Advanced age, hypertension, diabetes, obesity, malignancy, and cardiovascular disease predispose them to severe disease and the need for hospitalization. Data on pre-existing liver disease in patients with COVID-19 is limited, and most studies had only 3-8% of these patients. Patients with metabolic dysfunction-associated fatty liver (MAFLD) had shown a 4-6 fold increase in severity of COVID-19, and its severity and mortality increased in patients with higher fibrosis scores. Patients with chronic liver disease had shown that cirrhosis is an independent predictor of severity of COVID-19 with increased hospitalization and mortality. Increase in Child Turcotte Pugh (CTP) score and model for end-stage liver disease (MELD) score increases the mortality in these patients. Few case reports had shown SARS-CoV-2 as an acute event in the decompensation of underlying chronic liver disease. Immunosuppression should be reduced prophylactically in patients with autoimmune liver disease and post-transplantation with no COVID-19. Hydroxychloroquine and remdesivir is found to be safe in limited studies in a patient with cirrhosis and COVID-19. For hepatologists, cirrhosis with COVID-19 is a pertinent issue as the present pandemic will have severe disease in patients with chronic liver disease leading to more hospitalization and decompensation.

Patients with SARS-CoV-2 and HBV co-infection are at risk of greater liver injury.

To date, it remains unclear if severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) co-infection exacerbates liver injury in patients with chronic hepatitis B virus (HBV) infection. In this study, we present a retrospective study of 133 hospitalized confirmed mild coronavirus disease 2019 (COVID-19) cases, including 116 patients with COVID-19 with negative serum hepatitis B antigen and 17 HBV inactive carriers with COVID-19. We found that there were no significant differences for the discharge rate or duration of hospitalization between the two groups. However, inactive HBV carriers with SARS-CoV-2 co-infection are at a higher risk of abnormal liver function tests. The enhanced liver injury induced by SARS-CoV-2 and HBV co-infection was identified as the hepatocyte type rather than the cholangiocyte type. Moreover, the inflammatory response, including abnormal lactate dehydrogenase, D-dimer and interleukin-6 production, may contribute to this injury following SARS-CoV-2 co-infection. Collectively, SARS-CoV-2 and HBV co-infection exacerbates liver function of the patients with COVID-19.