Investigation of false-positive Mycobacterium tuberculosis culture tests using whole genome sequencing

• Main Authors: Jinsoo Min, Kyungjong Kim, Hongjo Choi, Eun Seok Kang, Yoon Mi Shin, Jin Young An, Kang Hyeon Choe, Ki Man Lee
• Format: Article
• Language: English
• Published: Wolters Kluwer Medknow Publications 2019-01-01
• Series: Annals of Thoracic Medicine
• Subjects: Drug resistance; molecular epidemiology; molecular typing; single nucleotide polymorphism
• Online Access: http://www.thoracicmedicine.org/article.asp?issn=1817-1737;year=2019;volume=14;issue=1;spage=90;epage=93;aulast=Min
• ISSN: 1817-1737; 1998-3557

Although accurate identification of Mycobacterium tuberculosis is the gold standard for tuberculosis (TB) diagnosis, there have been several reports of false-positive results. After identifying a sudden increase in extensively drug-resistant TB, false-positive mycobacterial culture tests were suspected, and we contacted the supranational reference center for molecular typing. In silico genotyping tests showed that isolates from all five patients had an identical genotype pattern, and all harbored the same Beijing strain based on sequence-based phylogenic analysis and drug-resistant single nucleotide polymorphisms (SNPs) analysis. We also used whole genome sequencing (WGS) to compare the SNPs of all isolates with a reference genome, and all were identical. We adapted WGS to efficiently detect false-positive MTB culture tests.