Detection of hepatitis C virus in paraffin-embedded liver biopsies of patients negative for viral RNA in serum.
The diagnosis of hepatitis C is based on serological testing for antibodies against various epitopes of the hepatitis C virus (HCV) and detection of HCV RNA in serum, because anti-HCV antibodies alone cannot discriminate patients who are infectious from those who have resolved the infection. If HCV RNA is not detected, which is the case in at least 20% of enzyme immunoassay (EIA)-positive patients, diagnosis remains unclear in a state of disease possibly well suited for therapeutic intervention. Therefore, we investigated if detection of HCV antigens or HCV RNA in routinely processed, formalin-fixed and paraffin-embedded (ffpe) liver biopsy specimens of patients positive for anti-HCV, but negative for HCV RNA in serum, could confirm diagnosis in this serological constellation. We detected HCV RNA by reverse-transcription polymerase chain reaction (RT-PCR) in 27 (61%) of 44 ffpe liver biopsies from EIA-positive, but HCV-RNA-seronegative, patients. Testing of 18 of these biopsies by a panel of polyclonal antibodies against structural and nonstructural HCV proteins revealed positive immunostaining in 6 cases (33%), which were also positive by RT-PCR. Most biopsies showed necroinflammation compatible with chronic hepatitis C, and the detection of tissue HCV RNA correlated significantly with a higher grade of inflammatory activity. Detectability of HCV RNA did not correlate with HCV subtype. In conclusion, the search for HCV RNA by RT-PCR within the liver biopsy specimen can establish rapid and unequivocal diagnosis of hepatitis C in at least 60% of anti-HCV antibody-positive patients who are seronegative for HCV RNA, and thus may help to avoid repeated testing and delayed therapy. Tissue RT-PCR may also be more efficient than serological testing for surveillance of interferon therapy response, because ongoing chronic active hepatitis C is clearly demonstrated in the absence of detectable serum HCV RNA.
Dries
V
V
Institute of Pathology, University of Cologne, Cologne, Germany.
von Both
I
I
Müller
M
M
Gerken
G
G
Schirmacher
P
P
Odenthal
M
M
Bartenschlager
R
R
Drebber
U
U
Meyer zum Büschenfeld
K H
KH
Dienes
H P
HP
D017931:DNA Primers; D016174:Hepacivirus / Q000737:chemistry* / Q000302:isolation & purification; D018936:Hepatitis C Antigens / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D008099:Liver / Q000276:immunology / Q000378:metabolism / Q000821:virology*; D016612:Paraffin Embedding; D012333:RNA, Messenger / Q000096:biosynthesis; D012367:RNA, Viral / Q000096:biosynthesis* / Q000097:blood / Q000235:genetics; D012189:Retrospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014764:Viral Proteins / Q000096:biosynthesis
D017931:DNA Primers; D018936:Hepatitis C Antigens; D012333:RNA, Messenger; D012367:RNA, Viral; D014764:Viral Proteins