Interpretation of positive transcription-mediated amplification test results from polymerase chain reaction-negative samples obtained after treatment of chronic hepatitis C.
The Siemens VERSANT transcription-mediated amplification (TMA) assay is extremely sensitive for the detection of hepatitis C virus (HCV) RNA in serum. Eleven of 180 subjects in the Hepatitis C Antiviral Long-term Treatment against Cirrhosis (HALT-C) Trial who achieved polymerase chain reaction (PCR)-defined sustained virological response (SVR) at week 72 also had TMA-positive results from the same blood draw; six were positive on repeat testing. We report the follow-up on these 11 patients, and the reproducibility of TMA test results from PCR-negative samples in relationship to antiviral treatment outcome. Peginterferon and ribavirin treatment was initiated in 1145 prior interferon nonresponders with advanced hepatic fibrosis. Treatment was continued for 48 weeks if patients had undetectable HCV RNA by PCR at treatment week 20. Frozen serum samples from weeks 12, 20, 24, 48, and 72 were subsequently tested by TMA. Nine of the 11 patients returned for testing (median, 30 months after the week 72 visit), and all had undetectable HCV RNA by TMA and PCR. Among 759 PCR-negative samples obtained during treatment that were tested twice by TMA, 17% overall exhibited consistently positive results, and 21% exhibited inconsistently positive results. SVR was more likely if TMA was consistently negative than if consistently or inconsistently positive. With continued treatment, patients with inconsistently positive TMA results were more likely to become TMA-negative than TMA-positive (P < 0.0001).


CONCLUSIONS
In PCR-negative samples, positive TMA results may indicate the presence of low levels of HCV RNA. However, because patients with positive TMA results may achieve SVR, management decisions during therapy should not be based on a single positive TMA test result.
Morishima
Chihiro
C
Department of Laboratory Medicine, Virology Division, University of Washington, Seattle, WA, USA.
Morgan
Timothy R
TR
Everhart
James E
JE
Wright
Elizabeth C
EC
Apodaca
Minjun C
MC
Gretch
David R
DR
Shiffman
Mitchell L
ML
Everson
Gregory T
GT
Lindsay
Karen L
KL
Lee
William M
WM
Lok
Anna S F
AS
Dienstag
Jules L
JL
Ghany
Marc G
MG
Curto
Teresa M
TM
D000998:Antiviral Agents / Q000627:therapeutic use*; D005784:Gene Amplification; D016174:Hepacivirus / Q000235:genetics* / Q000302:isolation & purification; D019698:Hepatitis C, Chronic / Q000188:drug therapy* / Q000235:genetics*; D006801:Humans; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000627:therapeutic use*; D008103:Liver Cirrhosis / Q000188:drug therapy / Q000821:virology; D011092:Polyethylene Glycols / Q000627:therapeutic use*; D016133:Polymerase Chain Reaction / Q000379:methods; D012367:RNA, Viral / Q000235:genetics; D011994:Recombinant Proteins; D015203:Reproducibility of Results; D014158:Transcription, Genetic; D019562:Viral Load
D000998:Antiviral Agents; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D012367:RNA, Viral; D011994:Recombinant Proteins; D011092:Polyethylene Glycols; C100416:peginterferon alfa-2a