The association of elevated alanine aminotransferase levels with hepatitis E virus infections among blood donors in China.

Abstract

Transfusion transmission of hepatitis E virus (HEV) is an emerging health risk, yet blood donors are rarely screened for this pathogen. Many blood centers instituted screening of blood donors for elevated levels of alanine aminotransferase (ALT) levels to prevent hepatitisC virus, which has continued in China. We evaluated whether elevated ALT levels were associated with HEV among blood donors in China. Blood samples were collected from 9069 qualified volunteer blood donors from four blood centers in China. A total of 5023 had elevated ALT levels, that is,more than 40IU/L, and 4046 samples had normal ALT. We tested all the 9069 samples for anti-HEV immunoglobulin (Ig)M, anti-HEV IgG, and HEV antigen. Those who were positive for anti-HEV IgM or HEV antigen were tested individually for HEV RNA by polymerase chain reaction. The prevalence of anti-HEV IgG in donors with elevated ALT levels (33.3%) was higher than those with normal ALT (24.9%; p<0.01). The prevalence of anti-HEV IgM was similar in donations with increased ALT (1.41%) and normal ALT (1.46%). More ALT-elevated donations were HEV antigen positive, 62 of 5023 (1.23%), than were ALT-normal donations, seven of 4046 (0.17%; p<0.01). Six donors with elevated ALT levels and acute HEV infection markers (anti-HEV IgM or HEV antigen) were HEV RNA positive. Markers of active infection including HEV antigen and HEV RNA are significantly more common among donors with elevated ALT levels in China. These data support the fact that ALT testing of donors to HEV antigen or HEV RNA would have greater specificity and exclude fewer acceptable donors.