Clinical Usefulness of the "MN Criteria" - the Clostridioides difficile Infection Severity Scoring System - in the Japanese Setting.

Objective The severity of Clostridioides difficile infection (CDI) is an important prognostic factor. The "MN criteria," proposed in Japan in 2017, attempted to remedy the shortfalls in the reported guidelines proposed globally to determine CDI severity. We therefore assessed the accuracy of the MN criteria and validated the important factors associated with predicting CDI severity. Methods Sixty-six CDI cases were investigated retrospectively at a Japanese University Hospital from January 2015 to December 2018. The fulminant cases were screened out, and the non-fulminant cases were classified according to their severity stages using the nine variables included in the MN criteria. Clinical events, such as death within 28 days, colectomy, and admission to the intensive care unit, were evaluated. First, the sensitivity and specificity of the MN criteria for predicting clinical events were determined. The relationships between clinical events and the explanatory variables were then evaluated through univariate and multivariate analyses. Results The screening of the fulminant cases and classification of the non-fulminant cases into mild/moderate and severe/super severe cases resulted in a sensitivity of 1.00 and a specificity of 0.89. Univariate and multivariate analyses revealed a significant association of the serum albumin (Alb) level as well as white blood cell (WBC) count with clinical events. Conclusion The findings provide evidence supporting the accuracy of the MN criteria in predicting CDI severity and show that the Alb and WBC are important variables in predicting CDI severity.