FXR inhibition may protect from SARS-CoV-2 infection by reducing ACE2.

Prevention of SARS-CoV-2 infection through the modulation of viral host receptors, such as ACE21, could represent a new chemoprophylactic approach for COVID-19 complementing vaccination2,3. However, the mechanisms controlling ACE2 expression remain elusive. Here, we identify the farnesoid X receptor (FXR) as a direct regulator of ACE2 transcription in multiple COVID19-affected tissues, including the gastrointestinal and respiratory systems. We then use the over-the-counter compound z-guggulsterone (ZGG) and the off-patent drug ursodeoxycholic acid (UDCA) to reduce FXR signalling and downregulate ACE2 in human lung, cholangiocyte and intestinal organoids and in the corresponding tissues in mice and hamsters. We demonstrate that UDCA-mediated ACE2 downregulation reduces susceptibility to SARS-CoV-2 infection in vitro, in vivo and in human lungs and livers perfused ex situ. Furthermore, we illustrate that UDCA reduces ACE2 expression in the nasal epithelium in humans. Finally, we identify a correlation between UDCA treatment and positive clinical outcomes following SARS-CoV-2 infection using retrospective registry data, and confirm these findings in an independent validation cohort of liver transplant recipients. In conclusion, we identify a novel function of FXR in controlling ACE2 expression and provide evidence that modulation of this pathway could be beneficial for reducing SARS-CoV-2 infection, paving the road for future clinical trials.

Severe acute hepatitis and acute liver failure of unknown origin in children: a questionnaire-based study within 34 paediatric liver centres in 22 European countries and Israel, April 2022.

To detect potential concern about severe acute hepatitis in children, we conducted a survey among 50 ERN RARE-LIVER centres. By 26 April 2022, 34 centres, including 25 transplant centres, reported an estimated median of 3-5, 0-2 and 3-5 cases in 2021, 2020 and 2019 and a mean of 2 (range: 0-8) cases between January and April 2022 (mean in 10 large liver transplant centres: 3). Twelve centres reported suspicion of an increase, but no rise.

SARS-CoV-2 Infection in patients with autoimmune hepatitis

OTH-1 Figure 1(A) AIH v non-AIH CLD (B) AIH v non-CLD[Figure omitted. See PDF]ConclusionDespite immunosuppressive treatment, AIH patients were not at increased risk of adverse outcomes from COVID-19 compared to other causes of CLD and to matched cases without liver disease.

Prevalence of COVID-19 in patients with autoimmune liver disease in Europe: A patient-oriented online survey.

BACKGROUND: During the current SARS-CoV-2 pandemic it is important to identify risk factors for COVID-19. Registry studies are providing growing evidence on the elevated risk of mortality from COVID-19 in patients with chronic liver disease, especially in advanced stages. Results may, however, have a selection bias towards severe cases. Limited data is available on COVID-19 in patients with autoimmune liver disease (AILD). AIM: To perform an online survey to capture the prevalence of COVID-19 and the state of medical care of patients with AILD in Europe during the pandemic. METHODS: Data was collected via an anonymous patient-oriented, online survey, which was available on the EUSurvey platform in nine European languages between 24th June 2020 and 14th October 2020. Of 1834 contributions, 51 were excluded because participants did not name an underlying AILD, and four were excluded because of duplicate data entry. RESULTS: Of 1,779 participants, 1,752 resided in 20 different countries of the European Union and the United Kingdom (UK). The five countries with the highest numbers of contributions were France (n = 450), Germany (n = 318), the Netherlands (n = 267), Spain (n = 225), and the UK (n = 183). 2.2% of participants (39/1779) had been diagnosed with COVID-19. There were no differences regarding age, sex, AILD, the status of liver cirrhosis, or status post liver transplantation between COVID-19 and non-COVID-19 cases. Of the 39 COVID-19 cases, five patients were admitted to a regular ward, one patient was admitted to ICU and required ventilation. CONCLUSION: In our Europe-wide, patient-oriented survey on COVID-19 in patients with AILD, we detected a low rate of COVID-19, comparable to the period prevalence of the general population. These results suggest that patients with AILD are not at elevated risk of COVID-19.

SARS-CoV-2 infection in patients with autoimmune hepatitis.

BACKGROUND & AIMS: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and coronavirus disease 2019 (COVID-19) continues to have a devastating impact across the globe. However, little is known about the disease course in patients with autoimmune hepatitis (AIH). METHODS: Data for patients with AIH and SARS-CoV-2 infection were combined from 3 international reporting registries and outcomes were compared to those in patients with chronic liver disease of other aetiology (non-AIH CLD) and to patients without liver disease (non-CLD). RESULTS: Between 25th March and 24th October 2020, data were collected for 932 patients with CLD and SARS-CoV-2 infection including 70 with autoimmune hepatitis (AIH). Fifty-eight (83%) patients with AIH were taking ≥1 immunosuppressive drug. There were no differences in rates of major outcomes between patients with AIH and non-AIH CLD, including hospitalization (76% vs. 85%; p = 0.06), intensive care unit admission (29% vs. 23%; p = 0.240), and death (23% vs. 20%; p = 0.643). Factors associated with death within the AIH cohort included age (odds ratio [OR] 2.16/10 years; 1.07-3.81), and Child-Pugh class B (OR 42.48; 4.40-409.53), and C (OR 69.30; 2.83-1694.50) cirrhosis, but not use of immunosuppression. Propensity score matched (PSM) analysis comparing patients with AIH with non-AIH CLD demonstrated no increased risk of adverse outcomes including death (+3.2%; -9.2%-15.7%). PSM analysis of patients with AIH vs. non-CLD (n = 769) demonstrated increased risk of hospitalization with AIH (+18.4%; 5.6-31.2%), but equivalent risk of all other outcomes including death (+3.2%; -9.1%-15.6%). CONCLUSION: Patients with AIH were not at increased risk of adverse outcomes despite immunosuppressive treatment compared to other causes of CLD and to matched cases without liver disease. LAY SUMMARY: Little is known about the outcomes of COVID-19 in patients with autoimmune hepatitis (AIH), a rare chronic inflammatory liver disease. This study combines data from 3 large registries to describe the course of COVID-19 in this patient group. We show that AIH patients do not appear to have an increased risk of death from COVID-19 compared to patients with other forms of liver disease and compared to patients without liver disease, despite the use of medications which suppress the immune system.