2 for 2: Fraud, plagiarism force retraction of Staph aureus paper

The Journal of Food Science has retracted a 2012 paper by Chinese scientists, one of whom copped to having made up data in the paper — which also plagiarized from a 2009 article by other researchers — and forging his co-authors’ names on the manuscript.

The article, “A Multiplex PCR Assay for the Rapid and Sensitive detection of Methicillin-Resistant Staphylococcus aureus and Simultaneous Discrimination of Staphylococcus aureus from Coagulase-Negative Staphylococci,” appeared online in October 2012 and was written by a group from Northwest A & F University, in Yangling, and Tianshui Normal University.

It has been cited once, according to Thomson Scientific’s Web of Knowledge. From the abstract:

Methicillin-resistant Staphylococcus aureus (MRSA) is a global health concern, which had been detected in food and food production animals. Conventional testing for detection of MRSA takes 3 to 5 d to yield complete information of the organism and its antibiotic sensitivity pattern. So, a rapid method is needed to diagnose and treat the MRSA infections. The present study focused on the development of a multiplex PCR assay for the rapid and sensitive detection of MRSA. The assay simultaneously detected 4 genes, namely, 16S rRNA of the Staphylococcus genus, femA of S. aureus, mecA that encodes methicillin resistance, and one internal control. It was rapid and yielded results within 4 h. The analytical sensitivity and specificity of the multiplex PCR assay was evaluated by comparing it with the conventional method. The analytical sensitivity of the multiplex PCR assay at the DNA level was 10 ng DNA. The analytical specificity was evaluated with 10 reference staphylococci strains and was 100%. The diagnostic evaluation of MRSA was carried out using 360 foodborne staphylococci isolates, and showed 99.1% of specificity, 96.4% of sensitivity, 97.5% of positive predictive value, and 97.3% of negative predictive value compared to the conventional method. The inclusion of an internal control in the multiplex PCR assay is important to exclude false-negative cases. This test can be used as an effective diagnostic and surveillance tool to investigate the spread and emergence of MRSA.

According to the retraction notice:

Retraction: “A Multiplex PCR Assay for the Rapid and Sensitive detection of Methicillin-Resistant Staphylococcus aureus and Simultaneous Discrimination of Staphylococcus aureus from Coagulase-Negative Staphylococci” by Benjin Xu, Ling Liu, Li Liu, Xinping Li, Xiaofang Li, and Xin Wang

The above article, published online on 26 October 2012 in Wiley Online Library (wileyonlinelibrary.com), and in Volume 77, No. 11, pp. M638-642, November 2012, has been retracted by agreement between the authors, the journal Editor in Chief, E. Allen Foegeding, and Wiley Periodicals, Inc. The retraction has been agreed due to data fabrication and unattributed overlap with “A Pentaplex PCR Assay for the Rapid Detection of Methicillin-Resistant Staphylococcus aureus and Panton-Valtentine Leucocidin” by Hassanain Al-Talib, Chan Yean, Yean, Alyaa Al-Khateeb, Habsan Hassan, Kirnpal-Kaur Banga Singh, Karim Al-Jashamy, and Manickam Ravichandran (BMC Microbiology 9:113, May 2009, doi: 10.1186/1471-2180-9-113).

Author Xu has confirmed that he alone committed this misconduct, submitting the article without the knowledge or agreement of his co-authors, and he accepts full responsibility for its publication.

The Journal of Food Science holds its authors to a high ethical standard and will not tolerate such misconduct. From mid-2010 through 2012, we randomly checked submitted papers for similarity to other sources via CrossCheck powered by iThenticate. In late 2012, just after Xu’s article was accepted, we began to require that all accepted papers had been run through a plagiarism check, and since May 2013, all papers are checked through iThenticate upon submission to ScholarOne Manuscripts.

Had the journal been using CrossCheck earlier in 2012, then, we gather it would have caught the similarities to the Al-Talib paper. Here’s the abstract from that article, which we found not with CrossCheck but with Google:

Staphylococcus aureus is a major human pathogen, especially methicillin-resistant S. aureus (MRSA), which causes a wide range of hospital and community-acquired infections worldwide. Conventional testing for detection of MRSA takes 2–5 days to yield complete information of the organism and its antibiotic sensitivity pattern.

…

The present study focused on the development of a pentaplex PCR assay for the rapid detection of MRSA. The assay simultaneously detected five genes, namely 16S rRNA of the Staphylococcus genus, femA of S. aureus, mecA that encodes methicillin resistance, lukS that encodes production of Panton-Valentine leukocidin (PVL), a necrotizing cytotoxin, and one internal control. Specific primer pairs were successfully designed and simultaneously amplified the targeted genes. The analytical sensitivity and specificity of the pentaplex PCR assay was evaluated by comparing it with the conventional method. The analytical sensitivity of the pentaplex PCR at the DNA level was found to be 10 ng DNA. The analytical specificity was evaluated with 34 reference staphylococci and non-staphylococcal strains and was found to be 100%. The diagnostic evaluation of MRSA carried out using 230 clinical isolates, showed 97.6% of sensitivity, 99.3% of specificity, 98.8% of positive predictive value and 98.6% of negative predictive value compared to the conventional method. The presence of an internal control in the pentaplex PCR assay is important to exclude false-negative cases. … The pentaplex PCR assay developed was rapid and gave results within 4 h, which is essential for the identification of Staphylococcus spp., virulence and their resistance to methicillin. Our PCR assay may be used as an effective surveillance tool to survey the prevalence of MRSA and PVL-producing strains in hospitals and the community.

Hat tip: Rolf Degen