Absence of Persistent Hepatitis E Virus Infection in Antibody-Deficient Patients Is Associated With Transfer of Antigen-Neutralizing Antibodies From Immunoglobulin Products.

BACKGROUND

Persistent hepatitis E virus (HEV) infection is described in a number of immunosuppressive conditions. We aimed to determine the risk of persistent HEV infection in patients with primary or secondary antibody deficiency.

METHODS

Two hundred forty-five antibody-deficient patients receiving regular immunoglobulin replacement therapy were tested for HEV RNA and anti-HEV immunoglobulin G (IgG). Immunoglobulin products and plasma specimens obtained from 9 antibody-deficient patients before and after intravenous immunoglobulin (IVIG) therapy, 5 recently treated patients with persistent HEV infection, and 5 healthy patients recovered from acute HEV infection were analyzed for anti-HEV IgG and for antibody reacting with HEV antigen.

RESULTS

No antibody-deficient patient had detectable plasma HEV RNA. Anti-HEV IgG was detected in 38.8% of patients. All 10 immunoglobulin products tested contained anti-HEV capable of neutralizing HEV antigen. Plasma samples collected following IVIG infusion therapy demonstrated a higher anti-HEV IgG level and neutralizing activity, compared with samples collected before IVIG therapy. Neutralizing activity was similar to that in healthy patients with recent acute HEV infection.

CONCLUSION

The risk of persistent HEV infection in patients with antibody deficiency appears extremely low. This may be due to passive seroprotection afforded by the ubiquitous presence of anti-HEV in immunoglobulin replacement products.