Comparative application of droplet-based digital and quantitative real-time PCR for human brucellosis detection

Xin Liu; Xiaoya Bao; Lanzhu Gao; Guangchen Li; Zeliang Chen; Jingbo Zhai

doi:10.1016/j.diagmicrobio.2023.116087

Comparative application of droplet-based digital and quantitative real-time PCR for human brucellosis detection

Diagn Microbiol Infect Dis. 2023 Dec;107(4):116087. doi: 10.1016/j.diagmicrobio.2023.116087. Epub 2023 Sep 13.

Authors

Xin Liu¹, Xiaoya Bao², Lanzhu Gao³, Guangchen Li³, Zeliang Chen⁴, Jingbo Zhai⁵

Affiliations

¹ Medical College, Inner Mongolia Minzu University, Tongliao, China.
² Medical College, Inner Mongolia Minzu University, Tongliao, China; The Second Affiliated Hospital of Baotou Medical College, Baotou, China.
³ Tongliao Infectious Disease Hospital, Tongliao, China.
⁴ Medical College, Inner Mongolia Minzu University, Tongliao, China; Key Laboratory of Zoonose Prevention and Control at Universities of Inner Mongolia Autonomous Region, Innovative Institute of Zoonoses, Inner Mongolia Minzu University, Tongliao, China; Brucellosis Prevention and Treatment Engineering Research Center of Inner Mongolia Autonomous Region, Tongliao, China.
⁵ Medical College, Inner Mongolia Minzu University, Tongliao, China; Key Laboratory of Zoonose Prevention and Control at Universities of Inner Mongolia Autonomous Region, Innovative Institute of Zoonoses, Inner Mongolia Minzu University, Tongliao, China; Brucellosis Prevention and Treatment Engineering Research Center of Inner Mongolia Autonomous Region, Tongliao, China. Electronic address: jbzhai@imun.edu.cn.

PMID: 37801887
DOI: 10.1016/j.diagmicrobio.2023.116087

Abstract

We evaluated the diagnostic value of droplet-based digital PCR (dd-PCR) by comparing it with the quantitative real-time PCR (RT-qPCR) for detecting Brucella DNA, 487 whole blood and serum samples collected from suspected human brucellosis, respectively. Sensitivity and specificity were 88.14% and 100% for RT-qPCR; 97.12% and 100% for dd-PCR. The positive rate detected by RT-qPCR and dd-PCR based on the nucleic acid extracted by simultaneous extraction method in serum and blood cells were 56.49% and 62.22%, respectively, which is higher than the commercial kit in 47.74% and 52.77%. Additionally, 32 false-negative samples of chronic patients analyzed by serological tests were positive in the detection from the blood cell nucleic acid. dd-PCR could be considered a valuable tool for detecting Brucella DNA, particularly in false-negative test results. The simultaneous extraction method is complementary to dd-PCR in diagnosing human brucellosis cases at different disease stages, especially in chronic and relapsed stages.

Keywords: Brucella; Diagnosis; Human brucellosis; RT-qPCR; Serological methods; dd-PCR.

MeSH terms

Brucellosis* / diagnosis
DNA
Humans
Nucleic Acids*
Real-Time Polymerase Chain Reaction / methods
Sensitivity and Specificity

Substances

DNA
Nucleic Acids