ABSTRACT
Objective:To explore the structure and diversity of intestinal flora in patients with community acquired pneumonia (CAP) before and after treatment with cefotaxime combined with levofloxacin.Methods:From October to December 2018, 6 patients with CAP in the Department of Infection, Zhejiang Provincial Hospital of Tongde, were treated with cefotaxime injection 2.0 g (once/8 h) combined with 0.5 g levofloxacin injection (once a day). A total of 12 fecal samples were collected before and after 7 days of treatment. The stool samples before and after treatment were analyzed by 16S rRNA sequencing.Results:⑴ The structure of intestinal flora before and after treatment : at the phylum level: Firmicutes 59.2% vs 40.8%, Proteobacteria 18.6% vs 35.5%, Bacteroidetes 14.8% vs 20.8%, Actinobacteria 5.6% vs 1.2%; At the family level: Ruminococcaceae 34.5% vs 13.0%, Lachnospiraceae 15.9% vs 9.7%, Veillonellaceae 1.8% vs 3.3%, Lactobacillaceae 0.3% vs 8.0%, Streptococcaceae 2.9% vs 1.1%, Enterococcaceae 0.02% vs 5.2%, Enterobacteriaceae 16.4% vs 34.6%, Bacteroidaceae 13.3% vs 16.8%, Porphyromonadaceae 0.3% vs 3.4%, Adlercreutzia 4.4% vs 0.5%. There was no significant difference in the composition and structure of intestinal flora before and after treatment ( P>0.05). ⑵ The diversity of intestinal flora before and after treatment: operational taxonomic units (OTU) mean (150.5±59.0) vs (93.2±34.1), t=2.72, P=0.04; Chao1 index (169.25±49.61) vs (117.92±35.06), t=3.22, P=0.02; shannon index (3.61±0.83) vs (2.31±0.73), t=4.54, P=0.01; simpson index (0.80±0.10) vs (0.61±0.20), t=2.76, P=0.04. There were significant differences in the diversity of intestinal flora before and after treatment ( P<0.05). ⑶ There was significant difference in desulfovibrio between the two groups before and after treatment (LDA=2.03, P=0.02). Conclusions:After intravenous infusion of cefotaxime combined with levofloxacin for one week , the diversity of intestinal flora was significantly reduced after treatment. Desulfovibrio was the flora with statistical differences between before and after treatment.
ABSTRACT
Objective To analyze the genotypes of Neisseria gonorrhoeae ( N. gonorrhoeae) epi-demic strains in Wenzhou, eastern China, and to study the mechanism of tetracycline resistance in these strains. Methods A total of 77 N. gonorrhoeae strains were isolated from patients with gonorrhea. Antimi-crobial susceptibility of these strains to penicillin, tetracycline, ciprofloxacin, spectinomycin, ceftriaxone and azithromycin was analyzed using E-test. PCR and DNA sequencing were used to detect the genes associ-ated with tetracycline resistance, such as Tet-M, mtrR promoter region and mtrR coding region. N. gonor-rhoeae multi-antigen sequence typing ( NG-MAST) and multilocus sequence typing ( MLST) were used to determine the molecular characteristics of all clinical isolates and tetracycline-resistant isolates, respectively. Results Among the 77 N. gonorrhoeae isolates, 74 (96. 10％), 27 (35. 06％) ,70 (90. 91％) and 15 (19. 48％) were resistant to penicillin, tetracycline, ciprofloxacin and azithromycin, respectively. All tested isolates were susceptible to spectinomycin and ceftriaxone. Nineteen isolates were resistant to tetracycline and all of them carried Tet-M gene. Among them, 17 had one deletion mutation of base A in mtrR promoter region and three had G45D mutation in mtrR coding region. NG-MAST classified the 19 tetracycline-resistant isolates into 11 different sequence types (ST). ST14781, ST1766 and ST1866 each accounted for 15. 79％(three strains). Two ST (10. 52％, 2/19) found in the present study had not been reported previously in the NG-MAST database. MLST showed the 19 tetracycline-resistant isolates belonged to 12 different STs, in which ST10899 accounted for 26. 32％ (five strains) and ST1600 accounted for 15. 79％ (three strains). Conclusions Mutations in mtrR promoter region and carrying Tet-M gene were associated with tetracycline resistance in N. gonorrhoeae. Clinical strains isolated in Wenzhou showed considerable molecular diversity. Measures should be implemented to monitor the spread of NG-MAST ST1766 and MLST ST1600 N. gonor-rhoeae clones with high resistance to tetracycline in Wenzhou.