High-Level Resistance of Toxigenic Clostridioides difficile Genotype to Macrolide-Lincosamide- Streptogramin B in Community Acquired Patients in Eastern China

摘要

Background: Clostridioides difficile resistant to macrolide-lincosamide-streptogramin B (MLSsubB/sub) has not been reported in China. Methods: In a cross-sectional study in two tertiary hospitals, C. difficile isolates from stool specimens from community-onset, hospital-associated diarrheal patients were analyzed for toxin genes, genotype, and antibiotic resistance, and the patients’ clinical charts were reviewed. Results: A total of 190 (15.2%) isolates (102 Asup+/supBsup+/sup and 88 Asup?/supBsup+/sup) from 1250 community acquired (CA) patients were recovered and all were susceptible to vancomycin and metronidazole. High-level resistance (minimum inhibitory concentration 128 mg/L) to erythromycin and clindamycin was recorded in 77.9% and 88.4% of the tested isolates, respectively. Furthermore, 89.3% (159/178) of the isolates resistant to MLSsubB/sub carried the erythromycin resistance methylase gene ( ermB ). The statistically significant factors associated with C. difficile infection (CDI) induced by Asup?/supBsup+/sup isolates with MLSsubB/sub resistance included a severity score of 2 (odds ratio [95% confidence interval], 7.43 [2.31– 23.87]) and platelet count (cells × 10sup 9/sup cells/L) 100 [5.19 (1.58– 17.04)]. The proportion of Asup?/supBsup+/sup increased with enhanced CDI severity ( xsup 2/sup = 21.62, P 0.001), which was significantly higher than that of ermB -positive Asup+/supBsup+/sup in severity score of 4 ( xsup 2/sup = 8.61, P = 0.003). The average severity score of ermB -positive isolates was significantly higher than that of ermB -negative isolates in Asup?/supBsup+/sup ( Z = ? 2.41, P = 0.016). Conclusion: The ermB -positive Asup?/supBsup+/sup C. difficile with MLSsubB/sub resistance is described for the first time as a potential epidemic clone inducing severe CDI in CA diarrheal patients in Eastern China.