“…Of the 26 studies included, 14 were conducted in Japan, [24,26,29,34,35,37–40,42–44,46,47] 5 in Italy, [27,30,36,41,45] 4 in the United States, [25,31,33] 1 each in Australia, [28] China, [49] and South Korea. [32] Fifteen studies enrolled patients with different stages of liver disease (chronic hepatitis or cirrhosis), [24,26,28,30,31,33,35–37,39,40,42,46,47,49] 2 studies involved patients with chronic hepatitis, [34,44] 5 studies patients with cirrhosis, [32,38,41,43,45] and 4 included also healthy controls. [25,27,29,48] The etiologic agent of liver disease was HCV in 18 studies, [24,28,29,31,33–37,39–47] alcohol in 2 studies, [32,38] primary biliary cirrhosis in 1, [49] whereas 5 studies [25–27,30,48] enrolled patients with a mixed etiology, HCV infection, alcohol abuse, and/or other nonspecified etiology.…”