What Has the COVID-19 Pandemic Taught Us so Far? Addressing the Problem from a Hepatologist’s Perspective

Méndez-Sánchez, Nahum; Valencia-Rodríguez, Alejandro; Qi, Xingshun; Yoshida, Eric M.; Romero-Gómez, Manuel; George, Jacob; Eslam, Mohammed; Abenavoli, Ludovico; Xie, Weifen; Teschke, Rolf; Carrion, Andres F.; Keaveny, Andrew P.

During the 2002 epidemic of SARS-CoV, some studies found an association between the severity of disease and the HLA-B*46:01 and HLA-B*07:03 alleles in Taiwanese and mainland Chinese populations, 7,8 respectively. In contrast, expression of the HLA-DRB1*03:01 allele conferred protection against the disease in both Taiwanese and mainland Chinese populations. 8, 9 Surprisingly, a recent in silico analysis of viral peptide-HLA interaction that awaits publication suggests that the HLA-B*46:01 allele could also impact the severity of COVID-19 and that the HLA-B*15:03 allele could confer immunity to the disease. 10 Vaccination policies between countries could be an important factor in susceptibility or protection against COVID-19. For example, it has been reported that the Bacillus Calmette-Guerin (commonly referred to as BCG) vaccine may confer protection against respiratory infections. Consistently, a recent study reported that countries that do not utilize the BCG vaccination routinely (Italy, the Netherlands, USA) have been most affected by COVID-19. 11 From a hepatologist's perspective, COVID-19 must be of concern, especially since infection with this virus has led to complications in other organs. In the case of the liver, the first study conducted in patients diagnosed with COVID-19 pneumonia (NCP) found that 43 of the 99 patients developed a degree of liver injury characterized by an increase in aspartate aminotransferase (AST) and alanine aminotransferase (ALT); 12 one patient developed severe liver injury (ALT 7590 U/L, AST 1445 U/L). In the latter case, acute liver injury secondary to hypoxic hepatitis could not be excluded. In the study, 97 patients (98%) had a decrease in serum albumin and 75 (76%) had increased levels of lactate dehydrogenase a generalized systemic inflammatory response to the virus could explain these findings. Guan et al. 13 carried out the largest study in NCP patients that included 1099 patients from 552 Chinese hospitals. They noted that patients with severe pneumonia were more likely to develop abnormal aminotransferase levels as compared with those with mild and moderate disease. A recent meta-analysis of four studies has also suggested an increased level of ALT is observed in 29% of patients with COVID-19. 14 Yao et al. 15 undertook a multiple regression analysis and suggested that the appearance of liver injury was probably related to the critical illness itself, with elevations of aminotransferases in the first week and hypoalbuminemia from the second week; both appear to be reversible with resolution of infection.