AUTHOR=Shen Yuhang , Lin Shan , You Peijun , Chen Yu , Luo Yun , Song Xiaojun , Chen Yunbo , Jin Dazhi 

TITLE=Rapid discrimination between clinical Clostridioides difficile infection and colonization by quantitative detection of TcdB toxin using a real-time cell analysis system

JOURNAL=Frontiers in Microbiology

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2024.1348892

DOI=10.3389/fmicb.2024.1348892

ISSN=1664-302X

ABSTRACT=<sec><title>Objectives</title><p>It is important to accurately discriminate between clinical <italic>Clostridioides difficile</italic> infection (CDI) and colonization (CDC) for effective antimicrobial treatment.</p></sec><sec><title>Methods</title><p>In this study, 37 stool samples were collected from 17 CDC and 20 CDI cases, and each sample were tested in parallel through the real-time cell analysis (RTCA) system, real-time PCR assay (PCR), and enzyme-linked immunosorbent assay (ELISA).</p></sec><sec><title>Results</title><p>RTCA-measured functional and toxical <italic>C. difficile</italic> toxin B (TcdB) concentrations in the CDI group (302.58 ± 119.15 ng/mL) were significantly higher than those in the CDC group (18.15 ± 11.81 ng/mL) (<italic>p</italic> = 0.0008). Conversely, ELISA results revealed no significant disparities in TcdB concentrations between the CDC (26.21 ± 3.57 ng/mL) and the CDI group (17.07 ± 3.10 ng/mL) (<italic>p</italic> = 0.064). PCR results indicated no significant differences in <italic>tcdB</italic> gene copies between the CDC (774.54 ± 357.89 copies/μL) and the CDI group (4,667.69 ± 3,069.87 copies/μL) (<italic>p</italic> = 0.407). Additionally, the functional and toxical TcdB concentrations secreted from <italic>C. difficile</italic> isolates were measured by the RTCA. The results from the CDC (490.00 ± 133.29 ng/mL) and the CDI group (439.82 ± 114.66 ng/mL) showed no significant difference (<italic>p</italic> = 0.448). Notably, RTCA-measured functional and toxical TcdB concentration was significantly decreased when mixed with pooled CDC samples supernatant (<italic>p</italic> = 0.030).</p></sec><sec><title>Conclusion</title><p>This study explored the novel application of the RTCA assay in effectively discerning clinical CDI from CDC cases.</p></sec>