Meta-Analysis
Copyright ©The Author(s) 2021.
World J Gastroenterol. Mar 28, 2021; 27(12): 1240-1254
Published online Mar 28, 2021. doi: 10.3748/wjg.v27.i12.1240
Table 1 Subgroup analyses of all variables
Subgroup
n (%)
Incidence (%)
95%CI

Year
< 20151017.19.9-27.9
≥ 2015826.819.5-35.7Q = 2.248, P = 0.134
Country
High-income1618.913.1-26.4
Middle-income241.837.6-46.1Q = 22.375, P < 0.001c
Study type
Prospective622.313.4-34.7
Retrospective1220.312.8-30.7Q = 0.077, P = 0.782
Sample size
n < 4001425.418.9-33.1
n ≥ 400410.43.2-28.8Q = 2.613, P = 0.106
Mean age
≤ 50 yr317.75.4-44.8
> 50 yr1020.213.4-29.3Q = 0.051, P = 0.821
Male proportion
≤ 65%716.07.7-30.4
> 65%523.012.5-38.5Q = 0.631, P = 0.427
Diagnostic test
More than one marker1125.919-34.4
Single marker714.15.5-31.5Q = 1.806, P = 0.179
Antibody assay
Wantai assay828.421.4-36.6
Other assays612.37.7-19.1Q = 10.134, P = 0.001b
Follow-up
≤ 12 mo723.823.8
> 12 mo426.826.8Q = 0.072, P = 0.789
Table 2 Characteristics of studies included in the systematic review
Ref.
Country
Type
n (%)
Organ
Age
Male
White
HEV
Confirmed test
Acute HEV
Death
Outcome
Follow-up
Kamar et al[19], 2011 MonacoR85UD---65.9% (total; 56/85). 32.1% (18/85) had clearance. 0% (0/18) reactivationPersistently elevated LFTs and positive HEV-RNA0%-Factors associated with chronic HEV infection: Tacrolimus (OR 1.89; 1.49-1.97). Low platelet (OR 1.02; 1.00-1.10)6 mo
Legrand-Abravanel et al[35], 2011 FranceR700Liver (n = 171), kidney (n = 529)5265.6%-15.1% (total; 106/700). 14.6% (25/171) for LTx. 15.3% (81/529 for KTx. 5.6% (de novo; 34/601). 0% (0/17) reactivationPositive HEV IgG, IgM (Adaltis assay) or HEV-RNA2.8% (17/611). 2.7% (4/150) for LTx. 2.8% (13/461) for KTx--22 mo
Pischke et al[22], 2012 GermanyP274Heart5780%-12.8% (total; 35/274). 7.3% (de novo; 20/274)Positive HEV IgG (MP assay) or HEV-RNA--Heart transplant recipients had significantly higher seroprevalence of HEV-IgG than healthy individuals8 mo
Crossan et al[21], 2014ScotlandP317UD56.493.4%-14.2% (total; 45/317)Positive HEV IgG or IgM (Wantai assay)0.9% (3/317)-Factors associated with chronic HEV infection: HBV coinfection (OR 7.4; 1.4-37). IgG positive is associated with HCC (OR 2.3; 1.1-4.8)-
Mallet et al[36], 2013 FranceR267Liver---31% (total; 83/267)Positive HEV IgG (Wantai assay)----
Pischke et al[37], 2014GermanyR95Lung---5.3% (total; 5/95)Positive HEV IgG (MP assay)----
Riezebos-Brilman et al[38], 2013 NetherlandsR468Lung4060%-2.1% (total; 10/468)Positive HEV-RNA-0.4%-6.5 mo
Abravanel et al[39], 2014 FranceP263Liver (n = 52), kidney (n = 211)5364.3%-38.4% (total; 101/263). 42.3% for LTx (22/52). 37.4% for KTx (79/211). 1.9% (de novo; 3/162)Positive HEV IgG, IgM (Wantai assay) or HEV-RNA---12 mo
Buffaz et al[40], 2014 FranceR206Liver41.163.0%-36.4% (total; 75/206). 5.3% (de novo; 11/206)Positive post-transplant HEV IgG, IgM (Wantai assay) or HEV-RNA---32.8 mo
Riveiro-Barciela et al[20], 2014 SpainR625Liver (n = 332), kidney (n = 296), dual (n = 6)54.560.8%-5.8% (total; 36/625). 3.7% (11/296) for KTx. 7.4% (25/332) for LTxPositive HEV IgG (MP assay)--Risk factors associated with HEV infection: Cirrhosis (OR 7.6; 4.4-13.1). Liver transplantation (OR 3.1; 1.8-5.4). HIV infection (OR 2.4; 1.3-4.4)-
De Nicola et al[41], 2015 ItalyR79Liver55--33% (total; 26/79). 5.7% (de novo; 3/53)Positive HEV IgG, IgM (Wantai assay), HEV-RNA0%--12 mo
Magnusson et al[42], 2015 SwedenP62Lung5537.5%100%14.8% (total; 8/54). De novo N/APositive HEV IgG (recomWell assay)25% (2/8)17.8%-12 mo
Sherman et al[43], 2017United StatesP171Liver (n = 70), kidney (n = 101)---19.9% (total; 34/171). 21.4% (15/70) for LTx. 18.8% (19/101) for KTxPositive HEV IgG (Wantai assay)5.5% (3/55) for LTx. 0% for KTx-HIV-infected transplant recipients24 mo
Erken et al[17], 2018 NetherlandsR677Kidney---0.7% (de novo; 2/300)Positive HEV-RNA--Subjects are patients with ALT elevations-
Reekie et al[18], 2018 United KingdomR611Liver (n = 262), kidney (n = 349)---0.5% (total; 3/611)Positive HEV-RNA---36 mo
Samala et al[44], 2018United StatesR232Liver (n = 208), kidney (n = 10), both (n = 10), intestine (n = 4)5865%70%19.4% (total; 45/232)Positive IgG, IgM (Wantai assay) or HEV-RNA--HEV seroprevalence was associated with older age and patients with the diagnosis of alcohol- or NAFLD-associated liver failure-
Darstein et al[45], 2020 GermanyR74Liver5562.2%-28.8% (total; 21/73)Positive HEV IgG (recomWell assay) or HEV-RNA----
Komolmit et al[46], 2020 ThailandP108Liver5869%0%44% (total; 48/108)Positive IgG, IgM (Wantai assay) or HEV-RNA2% (1/48)0.9%-12 mo
Wang et al[23], 2020 ChinaR408Liver5081.1%0%41.2% (total; 168/408). 16.9% (de novo; 69/408)Positive HEV-RNA more than 6 months13.7% (56/408)-Alcoholic cirrhosis (OR 5.324; 1.36-20.98). Liver failure (OR 23.76; 2.78-203.08). Graft rejection (OR 0.217; 0.06-0.74)13.7 mo
Zanotto et al[47], 2020 ItalyR120Liver---19.2% (total; 23/120)Positive HEV IgG, IgM (N/A assay) or HEV-RNA----