key: cord-0861573-wsz1m173
authors: Chen, Peng; Lei, Jiexin; Wu, Yue; Liu, Gang; Zhou, Benhong
title: Liver impairment associated with disease progression in COVID‐19 patients
date: 2020-04-15
journal: Liver Int
DOI: 10.1111/liv.14481
sha: 9ddf5afcb09ddaaae15fff343a080ce9349c01a9
doc_id: 861573
cord_uid: wsz1m173

We read with great interest the study by YF Zhang et al ([1]). The authors found that abnormalities of liver function tests are common in COVID‐19 patients, but the clinically significant liver dysfunction in COVID‐19 was not a prominent feature of this illness and also may not have serious clinical consequences. This study is important and interesting; however, we still have some concerns about it.

We read with great interest the study by YF Zhang et al [1] . The authors found that abnormalities of liver function tests are common in patients, but the clinically significant liver dysfunction in COVID-19 was not a prominent feature of this illness and also may not have serious clinical consequences. This study is important and interesting; however, we still have some concerns about it.

First, selection bias cannot be entirely excluded, although it is likely to be minimal as all COVID-19 patients during the study period were included and the community-acquired pneumonia (CAP) hospitalized patients (control group) was matched for age, sex, illness severity, some biochemistry

This article is protected by copyright. All rights reserved indicators and the admission time point. COVID-19 is a novel coronavirus with an outbreak of unusual viral pneumonia, and CAP is a commonly diagnosed illness in which no causative organism is identified in half the cases [2] . However, whether the CAP patients in the control group had chronic liver disease was still completely unclear in this study.

Another issue is that the logistic regression analysis in current study showed that the advanced age and high level of NLR were predictable risk factors for severe COVID-19, but the lymphocytes maybe ignored.

Lymphocytes are important for inhibiting overactive innate immune responses during viral infection. Typical lymphopenia during SARS-CoV-2 infection may result in increases in IL-6, IL-10 and IFN-γ levels and aggravated inflammatory responses, leading not only to pulmonary injury, but also the injury of non-pulmonary organs including the liver [3] . A study by Lu L et al investigated the risk factors involved with hepatic injury in patients with COVID-19, and found that lymphopenia and CRP level were independently associated with liver injury [4] . However, whether lymphopenia is an independent risk factor for severe COVID-19, and whether the results contradicts the data of Lu L et al or not, is still unknown in this study.

Furthermore, it has been reported that another possible contributing factor for hepatic injury in COVID-19 patients may be the high levels of positive end expiratory pressure that can cause hepatic congestion by increasing right atrial pressure and impeding venous return [5] . However, whether the patients with COVID-19 received mechanical ventilation remained unclear in current study. Additionally, it has been found that drug treatment during COVID-19 can also induce liver impairment. And it might be caused by antiviral medications (lopinavir/ritonavir), antipyretics (acetaminophen), antibiotics (macrolides, quinolones) or steroids [6] . In a paper describing the first 12 patients with COVID-19 in the United States (U.S.), the three hospitalized patients, who received remdesivir at the time of clinical worsening, reported elevated liver enzymes [7] . However, this issue has not been

This article is protected by copyright. All rights reserved mentioned in the current study, and the authors should give some interpretation and explanation of these data in the text.

Finally, as a cohort study, this research can reflect the "real-world" findings and further support the conclusion, but the cohort data may be influenced by bias due to the patient selection process. Therefore, a largescale study should be conducted in the future.

Liver impairment in COVID-19 patients: a retrospective analysis of 115 cases from a single center in Wuhan city

Radiological findings from 81 patients with COVID-19 pneumonia in Wuhan, China: a descriptive study

Longitudinal characteristics of lymphocyte responses and cytokine profiles in the peripheral blood of SARS-CoV-2 infected patients. medRxiv

Risk factors related to hepatic injury in patients with corona virus disease 2019

Clinical Characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in Wuhan, China

Clinical Features of COVID-19-Related Liver Damage. bioRxiv

First 12 patients with coronavirus disease 2019 (COVID-19) in the United States

We thank Fuchao Chen, the Department of Pharmacy, Dongfeng Hospital, Hubei University of Medicine, Shiyan, Hubei 442008, P.R. China, for providing relevant literature.

This work was supported by grants from the National Natural Science Foundation of China (31770381).

This article is protected by copyright. All rights reserved