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To grasp the epidemiological trend and drug resistance mechanisms of Clostridioides difficile (C. diff) in Beijing, 302 C. diff isolates were obtained from patients with diarrhea. The sequence types (STs) from mainstream strains were all susceptible to metronidazole, vancomycin, piperacillin/tazobactam, meropenem, and tigecycline but almost resistant to ciprofloxacin and clindamycin. The missense mutation of GyrA/GyrB and RpoB resulted in fluoroquinolone and rifamycin resistance, respectively. Toxigenic strains from clade IV were likely to be missed due to the deficiency of tcdA gene. Four tcdC genotypes were first detected in strains from clade III and IV. The truncating mutation of TcdC disabled its function working as a toxin suppressor. In conclusion, the molecular epidemiology of C. diff in Beijing is different from other regions of China. The antimicrobial resistance patterns and toxin-producing abilities of strains with different STs varied greatly, which suggests that continuous surveillance and control are meaningful and urgent. [ABSTRACT FROM AUTHOR]

Infection with cytotoxin-associated gene A (cagA)-positive Helicobacter pylori (H. pylori) is associated with severe gastrointestinal disease. A rapid, simple, and convenient detection method for cagA -positive H. pylori was an urgent need. We have developed and evaluated a duplex recombinase aided amplification combined with lateral flow dipstick (Duplex RAA-LFD) assay for detection of cagA -positive H. pylori strains. The Duplex RAA-LFD successfully detected DNA extracts in 25 min at 39°C, with visual detection limits of 1.2 × 102 CFU/mL and 10 pg, respectively. No positive amplification was observed in 6 non- H. pylori strains, indicating higher specificity. When testing 56 clinical isolates, the sensitivity and specificity of the Duplex RAA-LFD assay were 96% and 100%, respectively, with Duplex PCR serving as the reference method. Therefore, the Duplex RAA-LFD assay is a potential rapid and effective alternative to detect cagA -positive H. pylori strains in fresh gastric mucosal tissue. [ABSTRACT FROM AUTHOR]