582. Comparison of COBAS TaqMan and COBAS AMPLICORE Assays for Detection of  Mycobacterium tuberculosis complex, Mycobacterium avium and Mycobacterium intracellulare  in Culture-Positive Cases.  –Experience in Japan-
Session: Poster Abstract Session: Mycobacterial Diagnostics
Friday, October 21, 2011
Room: Poster Hall B1
Background:COBAS TaqMan MTB/MAI (Roche Diagnostics, CTM), which is a real-time PCR assay for Mycobacterium tuberculosis complex (MTB), Mycobacterium avium (MAV)  and Mycobacterium intracellulare (MIN), has been developed as the successor model of AMPLICORE Mycobacterium PCR (Roche Diagnostics, AMP). CTM can complete the assay in fewer hours (about three hours) than AMP. The purpose of this study is to evaluate the usefulness of COBAS TaqMan assay, comparing it to the existing COBAS AMPLICOR assay in culture-positive cases.

Methods: Consecutive clinical respiratory specimens from 412 culture-positive patients were examined by AMP assay between Jan 2007 and Dec 2009 (AMP specimens). Consecutive specimens from 181 culture-positive cases were tested by CTM assay between Jan 2010 and Dec 2010 (CTM specimens). The test performances of those assays were compared.

Results:There were no substantive differences in results of acid-fast smear, liquid culture, and solid culture between AMP specimens and CTM ones. Results of PCR detection rate in MTB, MAV and MIN were 77.23% (156/202), 62.60% (82/131), 62.03% (49/79) by AMP and 82.35% (56/68), 60.29% (41/68), 60.00% (27/45) by CTM, respectively There was no difference between both assays. In smear-negative cases, results of PCR detection rate in MTB, MAV and MIN were 54.55%, 46.67%, 47.27% by AMP and 63.64%, 46.00%, 40.00% by CTM. These also showed no difference.

Conclusion:This study was not a prospective head-to-head one. But AMP specimens and CTM ones showed similar characteristics of mycobacteriology. This study showed that both assays might have equivalent performance in detecting MTB, MAV and MIN. COBAS TaqMan and COBAS AMPLICORE assays for MTB, MAV and MIN might have equivalent performance. The former is suggested to be more useful because of increased rapidity and convenience.


Subject Category: D. Diagnostic microbiology

Ataru Moriya, Medical technologist1, Yoshiko Isobe, Medical technologist1, Masahiro Kobayashi, Medical technologist1, Minoru Kato, Medical technologist1, Masaaki Siina, Medical technologist1, Tadasi Tukahara, Medical technologist1, Hisami Konosaki, Medical technologist1, Sadao Aoki, Medical technologist1, Toru Tanaka, MD2, Yasuhiro Umezu, MD3, Simao Fukai, MD, PhD4 and Takefumi Saito, MD, PhD5, (1)Department of Clinical Laboratory, National Hospital Organization Ibarakihigasi Hospital, Ibaraki, Japan, (2)Department of Internal Medicine, National Hospital Organization Ibarakihigasi Hospital, Ibaraki, Japan, (3)Department of Clinical Research, National Hospital Organization Ibarakihigasi Hospital, Naka-gun, Ibaraki, Japan, (4)Department Of Respiratory Surgery, National Hospital Organization Ibarakihigasi Hospital, Ibaraki, Japan, (5)Departmen of Internal Medicine, National Hospital Organization Ibarakihigasi Hospital, Ibaraki, Japan

Disclosures:

A. Moriya, None

Y. Isobe, None

M. Kobayashi, None

M. Kato, None

M. Siina, None

T. Tukahara, None

H. Konosaki, None

S. Aoki, None

T. Tanaka, None

Y. Umezu, None

S. Fukai, None

T. Saito, None

Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.