Evidences suggest that liver injury can be seen in few cases of COVID-19 with its incidence ranging from 14–53%. The author of the present study evaluated the liver injury patterns and involvement of non-alcoholic fatty liver diseases (NAFLD) on clinical outcomes in patients with COVID-19.

The study include consecutive patients admitted to two designated COVID-19 hospitals with COVID-19 and data on NAFLD status were reviewed. The diagnosis and clinical management of patients with COVID-19 were done according to guidelines issued by The Chinese National Health Commission. The patient of COVID-19 was diagnosed by the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequences in the throat swab by reverse transcription PCR.

Liver injury was typified as hepatocellular if the alanine aminotransferase (ALT) level was >30 IU/L for males and >19 IU/L for females, ductular if alkaline phosphatase (ALP) was >the upper limit of normal (ULN) along with gamma-glutamyltransferase (GGT) >ULN; mixed if both hepatocellular and ductular enzymes were raised >ULN. NAFLD was confirmed with hepatic steatosis index (HSI = 8 × [ALT/AST] + BMI [+ 2 if type 2 diabetes yes, + 2 if female]) >36 points and/or by abdominal ultrasound examination. The ALT/AST value used for HSI was recorded either at complete recovery on discharge or from records of the patients before and within 12 months of the diagnosis of COVID-19. The patients were followed until discharged with recovery or disease progression. Clinical characteristics on admission were analyzed by univariate and multivariate logistic regression analysis was used to examine the independent risk factors for advancement of disease.

The outcome of the study revealed that out of the 202 recruited patients, liver injury was seen in 101 (50%) and 152 (75.2%) patients on admission and during hospitalization, respectively. Majority of liver injury was mild with hepatocellular pattern, out of which, 2.6% (4/152) had ductular or mixed pattern. Almost 33.2% patients exhibited persistent abnormal liver function from admission to last follow-up. Approximately 19.3% and 80.7% had progressive and stable disease, respectively. Moreover, patients with progressive disease were older, had higher BMI, and a higher percentage of comorbidity and NAFLD.

It was observed that male sex, age >60 years, higher BMI, underlying comorbidity and NAFLD were correlated with progression of COVID-19. The researchers also highlighted that patients with NAFLD had a higher risk of disease progression (6.6% vs. 44.7%), higher likelihood of abnormal liver function from admission to discharge (70% vs. 11.1%) and longer viral shedding time (17.5 ± 5.2 days vs. 12.1 ± 4.4 days) in contrast to patients without NAFLD.

Thus, the study concluded that although liver injury is a common finding in patients with COVID-19, it is usually mild in nature. The pattern of liver injury was found to be more hepatocellular in comparison to cholestatic, suggestive of the fact that biliary cells have high expression of angiotensin-converting enzyme (ACE2) receptor with a high affinity for the spike protein of SARS-CoV-2. The postmortem liver biopsy in one of the enrolled patients revealed only microvesicular steatosis, along with overactivation of T cells, indicative of the hypothesis that liver injury in COVID-19 can be immune mediated instead of being an outcome of direct cytopathic damage. The majority patients with persistent liver injury exhibited NAFLD and high BMI. Patients with NAFLD also showed a higher risk of progression to severe COVID-19 and longer viral shedding time, reflecting the higher risk of severe COVID-19 in large proportion of population.

Source: Ji D, Qin E, Xu J, et al. Non-alcoholic fatty liver diseases in patients with COVID-19: A retrospective study. J Hepatol. 2020;73(2):451-453.