COVID-19 and the liver: Are footprints still there?

Table 1 Studies showing the effect of various etiologies of liver disease on COVID-19

Ref.	Country	Study design	Study population	Sample size	Outcome
HBV
Anugwom et al[70], 2021	China	Letter	Peer reviewed articles with confirmed COVID-19 and HBV information	2054; HBV (n = 28)	Inverse relation of HBV with COVID-19
Kang et al[71], 2021	Korea	Retrospective, nationwide case-control study	Korean National Health Insurance Service COVID database	7723; HBV (n = 267)	Underlying chronic hepatitis B with COVID-19 severity (adjusted OR 0.65; 95%CI: 0.57-0.74)
HCV
Richardson et al[15], 2020	United States	Case series	With confirmed COVID-19 and information on HCV infection	5700	HCV infections in < 0.1% (n = 3) of COVID-19 patients
Ronderos et al[72], 2021	United States	Retrospective single-center	With confirmed COVID-19 and information on HCV infection	1193; HCV (n = 50)	HCV infection predictor of in hospital mortality
NAFLD
Ji et al[62], 2020	China	Retrospective	With confirmed COVID-19 and information on NAFLD status	202; NAFLD (n = 76)	HSI with disease progression (OR 6.4; 95%CI: 1.5-31.2)
Targher et al[64], 2020	China	Prospective observational	Laboratory confirmed COVID-19	310; NAFLD (n = 94)	FIB-4 (adjusted OR 1.90, 95%CI: 1.33 to 2.72) or NFS (adjusted OR 2.57, 95%CI: 1.73 to 3.82) with COVID-19 severity
Lopez-Mendez et al[65], 2021	Mexico	Retrospective	Medical records of hospitalized COVID-19	155; liver fibrosis (n = 69)	FIB-4 with risk of ICU admission (OR 1.74, 95%CI: 1.74-2.68; P = 0.023); mortality (OR 6.45, 95%CI: 2.01-20.83, P = 0.002)
Sachdeva et al[73], 2020	India	Systemic review	-	8142; NAFLD (n = 833)	Pooled adjusted 2.358 (95%CI: 1.902-2.923) with severity of COVID-19
Mahamid et al[74], 2021	Israel	Retrospective case-control	Medical records of COVID-19	71; NAFLD (n = 22)	OR 3.57 (95%CI: 1.22-14.48) with severity of disease
Hashemi et al[75], 2020	United States	Multicentre retrospective	Laboratory confirmed COVID-19	363; NAFLD (n = 55)	aOR 2.30 (95%CI: 1.27-4.17) with ICU admission
Yao et al[76], 2021	China	Retrospective	Laboratory confirmed COVID-19	86; NAFLD (n = 38)	OR 11.057 (95%CI: 1.193-102.439, P = 0.034) with severe COVID-19
Li et al[77], 2022	China and United States	Observational; 2-sample Mendelian randomization	Laboratory confirmed COVID-19	8267; NAFLD (n = 136)	OR 0.97 (95%CI: 0.88-1.08, P = 0.61) with COVID-19
BCS
Espinoza et al[78], 2021	Brazil	Case report	Laboratory confirmed COVID-19	-	Thrombosis of an abdominal vessel should be considered as a differential diagnosis in patients with undefined abdominal pain and elevated liver biochemical tests
Sh Hassan et al[79], 2021	Saudi Arabia	Case report	Laboratory confirmed COVID-19	-	Thromboembolic events could be the first manifestation of COVID-19

COVID-19: Coronavirus disease 2019; HBV: Hepatitis B virus; HCV: Hepatitis C virus; BCS: Budd-Chiari syndrome; HSI: Hepatic steatosis index; FIB-4: Fibrosis-4; NAFLD: Non-alcoholic fatty liver disease; NFS: Non-alcoholic fatty liver disease fibrosis score; 95%CI: 95% confidence interval; OR: Odds ratio.

Table 2 Impact of COVID-19 pandemic on hepatology services

Decrease	Increase
OPD follow-up and care	Inhospital admission
HBV treatment	Alcohol intake
HCV community level programs	HCC incidence
HCC surveillance and screening	Acute on chronic liver failure
UGI endoscopy	Gastrointestinal bleeding especially variceal bleeding
Liver transplantation	Unhealthy lifestyle
	NAFLD/MAFLD

OPD: Outpatient; COVID-19: Coronavirus disease 2019; HCC: Hepatocellular carcinoma; UGI: Upper gastrointestinal; NAFLD: Non-alcoholic fatty liver disease; MAFLD: Metabolic associated fatty liver disease.