Identification of serologically silent occult hepatitis C virus infection by detecting immunoglobulin G antibody to a dominant HCV core peptide epitope.
OBJECTIVE
Occult HCV infection has been described among anti-HCV-HCV RNA-negative individuals with abnormal transaminase values in whom HCV RNA is detected in liver.


METHODS
IgG antibody to an HCVcore-derived peptide (anti-HCVcore) was investigated in 145 patients with serologically silent occult HCV infection.


RESULTS
At the time of the diagnostic biopsy 45/145 (31%) occult HCV-infected patients tested IgG anti-HCVcore-positive but none of the 140 patients with HCV-unrelated liver disease (P<0.001). Among 23 IgG anti-HCVcore-positive patients at baseline, 22 remained antibody-reactive (one became antibody-negative). Similarly, 17/31 baseline anti-HCVcore-negative patients remained non-reactive whereas 14 seroconverted to IgG anti-HCVcore (although transiently in 10 patients). Thus, a total of 59/145 (40.7%) patients with occult HCV infection showed IgG anti-HCVcore reactivity at any time point analyzed, including 14 initially non-reactive patients. By supplemental immunoblot assay 16 sera reacted weakly with an HCVcore-peptide band (indeterminate result) of which 10 (62.5%) reacted in the IgG anti-HCVcore assay. Occult HCV-infected patients who tested anti-HCVcore-positive showed more frequently signs of necro-inflammation (P=0.035) and greater percentages of HCV RNA-positive hepatocytes (P=0.004) compared with those anti-HCVcore-negative.


CONCLUSIONS
This work documents that IgG anti-HCVcore testing identifies occult HCV infection among seronegative, non-viremic patients using screening tests and may be useful in tracking anti-HCV-negative infections.
Quiroga
Juan A
JA
Fundación para el Estudio de las Hepatitis Virales, Guzman el Bueno, 72 28015 Madrid, Spain.
Castillo
Inmaculada
I
Llorente
Silvia
S
Bartolomé
Javier
J
Barril
Guillermina
G
Carreño
Vicente
V
D000328:Adult; D000918:Antibody Specificity; D005260:Female; D006526:Hepatitis C / Q000175:diagnosis*; D018937:Hepatitis C Antibodies / Q000097:blood*; D006801:Humans; D016056:Immunodominant Epitopes; D007074:Immunoglobulin G / Q000097:blood*; D008297:Male; D008875:Middle Aged; D014758:Viral Core Proteins / Q000276:immunology*
D018937:Hepatitis C Antibodies; D016056:Immunodominant Epitopes; D007074:Immunoglobulin G; D014758:Viral Core Proteins