RESUMO
Investigate the biofilm-forming ability and drug resistance of Hypervirulent Klebsiella pneumoniae (HvKP) to provide scientific basis for the treatment of HvKP-infection. A total of 96 Klebsiella pneumoniae strains isolated from clinical infection specimens in Changsha Central Hospital from January to December in 2021 were retrospectively collected, and the clinical data of patients were collected. The string test preliminarily distinguished between HvKP and classic Klebsiella pneumoniae (CKP). The biofilm-forming ability of clinical strains of Klebsiella pneumoniae (KP) was determined by microplate method. The Vitek 2 Compact automatic microbial identification/drug sensitivity analysis system was used for bacterial identification and drug sensitivity test. The clinical data of patients, biofilm forming ability and drug resistance in the HvKP group and those in the CKP group were compared and analyzed. The results showed that a total of 20 strains of HvKP were isolated from 96 non-repetitive KP, and the detection rate was 20.8%. HvKP mainly come from respiratory specimens, up to 75.0%.The prevalence of hepatobiliary diseases and the infection rate of multiple sites in patients with HvKP infection were higher than those in patients with CKP infection, and the difference was statistically significant(χ2=5.184,7.488;P=0.023,0.006).There was no significant difference between the two groups in terms of gender, age, ICU admission, hypertension, diabetes, coronary heart disease, lung disease, urinary system disease, central nervous system disease and laboratory test indexes (all P>0.05).17 (85.0%) strains of HvKP can form biofilm, including 2 strains with weak biofilm-forming ability (10.0%), 10 strains with moderate biofilm-forming ability (50.0%) and 5 strains with strong biofilm-forming ability (25.0%). Among the 76 CKP, 71 (93.4%) could form biofilm, including 13 (17.1%) with weak biofilm-forming ability, 30(39.5%) with moderate biofilm-forming ability and 28 (36.8%) with strong biofilm-forming ability. There was no significant difference in biofilm-forming ability between HvKP and CKP (χ2=1.470,P=0.225).The overall resistance rate of HvKP was not high, but a multi-resistant HvKP resistant to carbapenems was found. The detection rate of multi-resistant HvKP (5.0%) was lower than that of multi-resistant CKP (28.9%), and the difference was statistically significant (χ2=4.984, P=0.026).The resistance rate of HvKP to piperacillin/tazobactam, aztreonam, ciprofloxacin, levofloxacin, ceftazidime, cefepime, tobramycin, minocycline, doxycycline, and compound sulfamethoxazole was lower than that of CKP, and the difference was statistically significant (all P<0.05). In conclusion, most of hypervirulent Klebsiella pneumoniae can form biofilm in this study, but the difference of biofilm-forming ability is not obvious compared with classic Klebsiella pneumoniae. HvKP maintains high sensitivity to commonly used antibacterial drugs, but the drug resistance monitoring of the bacteria cannot be ignored.
RESUMO
To explore the correlation between the changes of the intestinal flora of newly treated pulmonary tuberculosis patients and the immune indicators of the body, and to provide a reference for the prevention and treatment of pulmonary tuberculosis. A single-center and case-control study was adopted. From October 2020 to April 2021, 43 patients with newly diagnosed tuberculosis in the Department of Tuberculosis, Affiliated Changsha Central Hospital,University of South China were selected as the control group. 43 cases of newly treated pulmonary tuberculosis (PTB), 43 healthy control (HC) during the same period, collected fresh feces and whole blood of subjects, and used Illumina Hiseq high-throughput sequencing technology to analyze 16S of all microorganisms in feces The V4 region of rRNA was amplified and sequenced, and the structure of the intestinal flora was analyzed by QIIME software. Use flow cytometry to determine the subject's immune indicators (CD3+, CD4+, CD8+, CD4+CD25+CD127-Treg, CD14+CD16+, CD14+CD16-), and analyze the changes in intestinal flora and immune function in newly treated pulmonary tuberculosis patients Inherent connection. The χ² test, t test, and Wilcox rank sum test were used to analyze the differences in age, gender, α diversity, and relative abundance of the two groups of people. Compared with the HC group, the alpha diversity of the intestinal flora in the PTB group decreased (shannon index: t=3.906, P=0.000 2; simpson index: Z=553, P=0.004 7; chao1 index: t=5.395, P=0.000 0). ß diversity analysis showed that there were significant differences in the structure of the intestinal flora between the two groups (P=0.000). Species difference analysis showed that at the phylum level, the relative abundance of Firmicutes in the PTB group was significantly lower than that in the HC group (Z=486.0, P=0.000 5). At the genus level, there are 15 different bacterial genera between the two groups. In the PTB group, bifidobacterium, enterococcus, lactobacillus, anaerostipes, the relative abundance of the above 5 genera of veillonella is higher than that of the HC group (P<0.05); Butyricimonas, clostridium, and broutella (blautia), coprococcus, dorea, lachnospira, roseburia, faecalibacterium, ruminococcus, the relative abundance of 10 bacterial genera including dialister was lower than that of the HC group (P<0.05). Comparison of immune indexes between groups showed that CD14+CD16+monocytes (%) in the PTB group were higher than those in the HC group (t=2.456, P=0.001 6<0.05), while CD14+CD16-monocytes (%) were lower than HC (t=-4.368, P=0.000<0.05), while the differences in CD3+, CD4+, CD8+, CD4+/CD8+and Treg (CD4+CD25+CD127-) were not statistically significant (P>0.05). Spearman correlation analysis showed that Firmicutes in the PTB group was negatively correlated with CD4+/CD8+, CD14+CD16+(r=-0.218, P=0.048; r=-0.245, P=0.025), and positively correlated with CD14+CD16-Correlation (r=0.250, P=0.022); At the genus level, Faecalis is positively correlated with CD4+/CD8+and CD4+(r=0.250, P=0.023; r=0.258, P=0.019); Rosella and CD3+, CD8+and CD14+CD16-are positively correlated (r=0.27, P=0.024; r=0.219, P=0.046; r=0.027, P=0.039), and negatively correlated with CD14+CD16+(r=-0.280, P= 0.01). Changes in the structure of the intestinal flora of newly treated pulmonary tuberculosis patients may be one of the influencing factors of the immune function of the body. Targeted optimization of the structure of the intestinal flora and improvement of the body's immunity may be used as an effective auxiliary treatment for pulmonary tuberculosis.