Rapid detection assay of toxigenic Clostridioides difficile through PathOC RightGene, a novel high-speed polymerase chain reaction device

Epidemiological and microbiome associations of Clostridioides difficile carriage in infancy and early childhood

There has been an increase in the prevalence of Clostridioides difficile (C. diff) causing significant economic impact on the health care system. Although toxigenic C. diff carriage is recognized in infancy, there is limited data regarding its longitudinal trends, associated epidemiolocal risk factors and intestinal microbiome characteristics. The objectives of our longitudinal cohort study were to investigate temporal changes in the prevalence of toxigenic C.diff colonization in children up to 2 years, associated epidemiological and intestinal microbiome characteristics. Pregnant mothers were enrolled prenatally, and serial stool samples were collected from their children for 2 years. 2608 serial stool samples were collected from 817 children. 411/817 (50%) were males, and 738/817 (90%) were born full term. Toxigenic C.diff was detected in 7/569 (1%) of meconium samples, 116/624 (19%) of 2 m (month), 221/606 (37%) of 6 m, 227/574 (40%) of 12 m and 18/235 (8%) of 24 m samples. Infants receiving any breast milk at 6 m were less likely to be carriers at 2 m, 6 m and 12 m than those not receiving it. (p = 0.002 at 2 m, p < 0.0001 at 6 m, p = 0.022 at 12 m). There were no robust differences in the underlying alpha or beta diversity between those with and without toxigenic C. diff carriage at any timepoint, although small differences in the relative abundance of certain taxa were found. In this largest longitudinal cohort study to date, a high prevalence of toxigenic C. diff carrier state was noted. Toxigenic C. diff carrier state in children is most likely a transient component of the dynamic infant microbiome.

Usefulness of a newly developed high-speed polymerase chain reaction analysis system for the diagnosis of Clostridioides difficile infection

INTRODUCTION

The incidence of Clostridioides difficile infection (CDI) has been continuously increasing and thereby became an important issue worldwide. Appropriate diagnosis, management, and infection control are required for patients with CDI. Enzyme immunoassay (EIA) is a widely used standard diagnostic tool for C. difficile-specific glutamate dehydrogenase (GDH) and C. difficile toxins (toxins A and B). However, the sensitivity of EIA in detecting C. difficile toxins has been reported to be relatively low, resulting in CDI underdiagnosis. Therefore, nucleic acid amplification tests (NAAT) are recently developed for higher sensitivity/specificity test.

METHODS

In this study, a total of 279 stool samples submitted for CDI diagnosis were examined using an independently developed new high-speed polymerase chain reaction (PCR) device (PathOC RightGene, Metaboscreen). In parallel, results were compared with those of definitive diagnosis and conventional diagnostic methods (EIA, real-time PCR) to assess the inspection accuracy.

RESULTS

PathOC RightGene showed high sensitivity (96.7%) and specificity (96.7%). Regarding the measurement time, C. difficile-specific and C. difficile toxin genes were simultaneously detected in approximately 25 min for one sample (including the preprocessing and measurement time).

CONCLUSION

PathOC RightGene has been found to show both excellent sensitivity and rapidity and thus can be used for the reliable and early diagnosis, which are needed for the appropriate management of CDI.