RÉSUMÉ
Under the Korean Association of External Quality Assessment Service,autoimmune proficiency testings (PT) for six test items were performed in2018–2019 for laboratory quality improvement. We conducted two trials peryear and sent three PT materials for anti-nuclear antibody (ANA) testing andtwo PT materials for anti-mitochondrial antibody (AMA), anti-smooth muscleantibody (SMA), anti-thyroglobulin antibody (anti-Tg), anti-thyroperoxidaseantibody (anti-TPO), and anti-double stranded DNA antibody (anti-dsDNA)testing in each trial. The analysis was conducted based on the informationand results of each test item entered by the laboratory. The report comprisedof a common report that showed the characteristics of all the participatinglaboratories and a laboratory-specific report that showed the assessmentdata of individual laboratories. The intended response rates for ANA, AMA,SMA, and anti-dsDNA qualitative tests were over 97.5%, 88.2%, 85.0%, and90.4%, respectively. The coefficient of variations for anti-Tg and anti-TPO was10.4%–70.1% and 16.6%–21.0%, respectively. The number of participatinglaboratories in 2019 was more than that in 2018. We believe this statisticalreport will be useful to interpret external PT results and set up autoimmuneassays at each laboratory.
RÉSUMÉ
Background@#Current methods for diagnosing Clostridioides difficile infections (CDIs) fail to provide information on their severity. Fecal neutrophil gelatinase-associated lipocalin (NGAL) and calprotectin are candidate biomarkers for evaluating the severity of intestinal inflammation. We assessed fecal NGAL and calprotectin levels in patients with CDI and compared these values between subgroups of patients. We also evaluated their utility in predicting CDI clinical outcomes. @*Methods@#A total of 147 leftover fecal samples were obtained; 97 samples were from patients with CDI and 50 were from routine healthcare checkups. Fecal calprotectin and NGAL levels were measured using a Quantitative Fecal NGAL ELISA Kit and Quantitative Fecal Calprotectin ELISA Kit (Epitope Diagnostics, USA). @*Results@#Significant differences in fecal NGAL and calprotectin levels were observed between CDI patients and healthy controls (P<0.0001 for both). Significant differences in fecal NGAL and calprotectin levels were also seen between patients with high and low tcdB gene load (P=0.005 and 0.006, respectively). Fecal calprotectin levels were lower in patients with leukopenia (P=0.002), and high calprotectin levels were associated with severe CDI and treatment failure (P=0.021 and 0.033, respectively). @*Conclusions@#Fecal NGAL and calprotectin levels were higher in patients with CDI than in healthy controls and correlated with high tcdB gene loads. Leukopenia patients with CDI had significantly lower levels of calprotectin and the assessment should be regarded with caution. High fecal calprotectin levels were also associated with severe CDI and treatment failure. This warrants future studies with more patients and in-depth analyses.