INSTRUCTION: Using the lesson as guide, read the academic text below; evaluate it, describe
the nature of the academic text as it is presented in a research study.
RESEARCH TITLE: Evaluation of the illumigene C. difficile assay for toxigenic Clostridium difficile
detection: a prospective study of 302 consecutive clinical fecal samples
AUTHORS: Geehay Hong, Kyung Sun Park, Chang-Seok Ki, and Nam Yong Lee
Abstract
Toxigenic Clostridium difficile is a major pathogen causing nosocomial diarrhea. Consequently,
rapid detection of toxigenic C. difficile is very important in clinical laboratories. The
illumigene C. difficile DNA amplification assay (illumigene; Meridian Bioscience, Inc.) is a rapid
method that detects the toxin A gene (tcdA) by loop-mediated isothermal amplification. In the
present study, we evaluated the diagnostic performance of the illumigene assay using 302
consecutive stool specimens in comparison with the VIDAS C. difficile A&B enzyme-linked
fluorescent immunoassay (VIDAS-CDAB; bioMérieux). Toxigenic culture was used as the
reference method. The sensitivity, specificity, positive predictive value, and negative predictive
value of the illumigene assay were 88.1%, 96.7%, 86.7%, and 97.1%, respectively, while those of
the VIDAS-CDAB assay were 40.4%, 98.8%, 87.5%, and 88.5%, respectively. It is of note that use
of a combination of the illumigene and VIDAS-CDAB assays did not improve any of the 4
evaluated parameters (88.1%, 95.5%, 82.5%, and 97.1%, respectively). The illumigene assay
showed limits of detection of 250 and 11,467 CFU/mL for ATCC 9688 (tcdA+, tcdB+, cdtB−) and
ATCC 43598 (tcdA−, tcdB+, cdtB−) reference strains, respectively, and there was no cross-
reactivity with 8 frequently isolated bacterial species. In conclusion, the illumigene assay might
be a useful method for rapid detection of toxigenic C. difficile in clinical laboratories.
Additionally, the VIDAS-CDAB assay seems unnecessary if the illumigene assay is used.
Department of Laboratory Medicine and Genetics, Sungkyunkwan University School of
Medicine, Seoul, Republic of Korea
Received 31 May 2014, Revised 25 August 2014, Accepted 27 August 2014, Available
online 2 September 2014.
What is the title?
- Evaluation of the illumigene C. difficile assay for toxigenic Clostridium difficile detection:
a prospective study of 302 consecutive clinical decal samples
Who is the author?
- Geehay Hong, Kyung Sun Park, Chang-Seok Ki and Nam Yong Lee
the nature of the academic text as it is presented in a research study.
RESEARCH TITLE: Evaluation of the illumigene C. difficile assay for toxigenic Clostridium difficile
detection: a prospective study of 302 consecutive clinical fecal samples
AUTHORS: Geehay Hong, Kyung Sun Park, Chang-Seok Ki, and Nam Yong Lee
Abstract
Toxigenic Clostridium difficile is a major pathogen causing nosocomial diarrhea. Consequently,
rapid detection of toxigenic C. difficile is very important in clinical laboratories. The
illumigene C. difficile DNA amplification assay (illumigene; Meridian Bioscience, Inc.) is a rapid
method that detects the toxin A gene (tcdA) by loop-mediated isothermal amplification. In the
present study, we evaluated the diagnostic performance of the illumigene assay using 302
consecutive stool specimens in comparison with the VIDAS C. difficile A&B enzyme-linked
fluorescent immunoassay (VIDAS-CDAB; bioMérieux). Toxigenic culture was used as the
reference method. The sensitivity, specificity, positive predictive value, and negative predictive
value of the illumigene assay were 88.1%, 96.7%, 86.7%, and 97.1%, respectively, while those of
the VIDAS-CDAB assay were 40.4%, 98.8%, 87.5%, and 88.5%, respectively. It is of note that use
of a combination of the illumigene and VIDAS-CDAB assays did not improve any of the 4
evaluated parameters (88.1%, 95.5%, 82.5%, and 97.1%, respectively). The illumigene assay
showed limits of detection of 250 and 11,467 CFU/mL for ATCC 9688 (tcdA+, tcdB+, cdtB−) and
ATCC 43598 (tcdA−, tcdB+, cdtB−) reference strains, respectively, and there was no cross-
reactivity with 8 frequently isolated bacterial species. In conclusion, the illumigene assay might
be a useful method for rapid detection of toxigenic C. difficile in clinical laboratories.
Additionally, the VIDAS-CDAB assay seems unnecessary if the illumigene assay is used.
Department of Laboratory Medicine and Genetics, Sungkyunkwan University School of
Medicine, Seoul, Republic of Korea
Received 31 May 2014, Revised 25 August 2014, Accepted 27 August 2014, Available
online 2 September 2014.
What is the title?
- Evaluation of the illumigene C. difficile assay for toxigenic Clostridium difficile detection:
a prospective study of 302 consecutive clinical decal samples
Who is the author?
- Geehay Hong, Kyung Sun Park, Chang-Seok Ki and Nam Yong Lee
