Objective To analyze the molecular epidemiology and colistin-resistant genes of carbapenem-resistant Klebsiella pneumoniae(CRKP)by whole-genome sequencing,and to provide reference for clinical diagnosis and treatment.Methods 57 CRKP strains isolated from clinical specimens of hospitalized patients in a tertiary general first-class hospital in Anhui Province from 2021 to 2023 were collected and antimicrobial susceptibility testing was performed.Multilocus sequence typing,capsule serotype,resistance genes,and virulence genes of CRKP strains were analyzed by whole-genome sequencing technique,and single nucleotide polymorphism analysis was conducted on sequences of all strains.Colistin resistance-related genes were amplified by polymerase chain reaction(PCR).Results 57 CRKP strains exhibited resistance to 14 antimicrobial agents,with the exception of tigecycline.The se-quencing results showed that 93.0％(53/57)of CRKP carried blaKPC-2,and the ST11 type CRKP strain had the highest detection rate(51/57,89.5％).Single nucleotide polymorphism clustering analysis showed that the 57 CRKP strains were divided into 11 clone groups,of which 4 clone groups were all ST11-KL64 type CRKP.40(70.2％)CRKP strains carried multiple virulence genes.Five strains of CRKP were colistin-resistant strains,the resistance mechanism involved the insertion of ISKpn26 element at site 70 of the mgrB gene.Conclusion The CRKP strain is primarily characterized by the production of KPC-2 ST11-KL64,with disseminated transmission in intensive care unit.The insertion of ISKpn26 element leading to mgrB gene mutation is related to resistance of CRKP to colistin in this region.

Objective To analyze the molecular epidemiology and colistin-resistant genes of carbapenem-resistant Klebsiella pneumoniae(CRKP)by whole-genome sequencing,and to provide reference for clinical diagnosis and treatment.Methods 57 CRKP strains isolated from clinical specimens of hospitalized patients in a tertiary general first-class hospital in Anhui Province from 2021 to 2023 were collected and antimicrobial susceptibility testing was performed.Multilocus sequence typing,capsule serotype,resistance genes,and virulence genes of CRKP strains were analyzed by whole-genome sequencing technique,and single nucleotide polymorphism analysis was conducted on sequences of all strains.Colistin resistance-related genes were amplified by polymerase chain reaction(PCR).Results 57 CRKP strains exhibited resistance to 14 antimicrobial agents,with the exception of tigecycline.The se-quencing results showed that 93.0％(53/57)of CRKP carried blaKPC-2,and the ST11 type CRKP strain had the highest detection rate(51/57,89.5％).Single nucleotide polymorphism clustering analysis showed that the 57 CRKP strains were divided into 11 clone groups,of which 4 clone groups were all ST11-KL64 type CRKP.40(70.2％)CRKP strains carried multiple virulence genes.Five strains of CRKP were colistin-resistant strains,the resistance mechanism involved the insertion of ISKpn26 element at site 70 of the mgrB gene.Conclusion The CRKP strain is primarily characterized by the production of KPC-2 ST11-KL64,with disseminated transmission in intensive care unit.The insertion of ISKpn26 element leading to mgrB gene mutation is related to resistance of CRKP to colistin in this region.

Objective:The whole-genome sequencing and virulence characteristics analysis of a Klebsiella pneumoniae isolate that caused lower limb gas gangrene were performed to provide a reference for the comprehensive understanding of molecular virulence characteristics of K. pneumoniae causing severe community-acquired infection. Methods:The patient was admitted to the emergency department for treatment on March 13, 2018.The main clinical symptoms of the patients were high fever, gas gangrene of the left lower limb, and diabetic ketoacidosis. The pus specimen was collected for the bacterial culture, isolates identification and antimicrobial susceptibility testing. Hypermucoviscous phenotype was detected by string test. The whole genome of the isolate was sequenced and the multi-site sequence typing, capsular serotyping, plasmid characteristics, virulence and antimicrobial resistance genes of the isolate were analyzed. Plasmid curing and conjugation experiments were used to analyze plasmid characteristics. The virulence of the strain was assessed by serum killing and Galleria mellonella lethality assays. A two-sample t-test was used to compare the differences in the lethal dose of 50% (LD 50) between the tested strains and reference strains against the G. mellonella larvae. Results:K. pneumoniae strain KPN41053 was identified, it was only resistant to ampicillin and was negative for hypermucoviscous phenotype. Whole genome sequencing showed that the length of KPN41053 chromosome was 5 377 071 bp, belonging to ST660 type, and the capsular type was K16. A IncFIB(K)/HI1B virulence plasmid (207 506 bp) with a sequence that was highly similar to pLVPK was harbored by KPN41053. The plasmid carried a variety of virulence genes, among which rmpA and rmpA2 were pseudogenes. The plasmid could not be transferred horizontally by conjugation. The variation strain KPN41053_PC was obtained by plasmid curing. Serum killing analysis showed that KPN41053 was serum resistant (Grade 6), and KPN41053_PC was serum intermediately sensitive (Grade 3). The lgLD 50 of KPN41053 had no difference with that of the hypervirulent control strain (ST23-K1 type) ( t=0.32, P=0.765), and was significantly lower than that of KPN41053_PC ( t=5.97, P=0.004). Conclusions:KPN41053 was an atypical hypervirulent K. pneumoniae that belonged to ST660 but without a hypermucoviscous phenotype. The virulence plasmid harbored by KPN41053 was its key virulence factor. Hypervirulent K. pneumoniae can lead to community-acquired gas gangrene in diabetic patient, which deserves clinical attention.

Objective:To investigate the detection rate of intestinal colonization of carbapenem-resistant Enterobacterales (CRE) in inpatients, and to analyze the molecular epidemiological characteristics of CRE strains.Methods:This was a prospective study. Stool, rectal swab or perianal swab specimens of 213 inpatients in the surgical intensive care unit (SICU), medical intensive care unit (MICU) and the department of hematology (transplantation ward) in The Second Hospital of Anhui Medical University were collected from March to December, 2019. MacConkey plate containing carbapenems was used to screen CRE strains, and bacteria identification and drug susceptibility test were conducted. Key strains were selected for whole genome sequencing (WGS). Besides, multilocus sequence typing, capsular serotype, drug resistance gene, virulence gene and plasmid carrying characteristics of these strains were analyzed. Using KPN FJ723042 sequence as a reference, the single-nucleotide polymorphism (SNP) of all strains was analyzed.Results:Twenty-three CRE strains were detected, with a detection rate of 10.8%(23/213), which included 15(65.2%) carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates, three (13.0%) Escherichia coli strains, three (13.0%) Enterobacter cloacae strains and two (8.7%) Citrobacter freundii strains. SNP cluster analysis showed that the 15 CRKP strains had two main clonotypes, which were both predominant in SICU. Fifteen strains of CRKP were type ST11-K64. All these strains carried β-lactamase Klebsiella pneumoniae carbapenemase 2 ( blaKPC-2 ), and 12 strains carried regulator of mucoid phenotype gene A2 ( rmpA2) and iucABCD. Conclusions:The detection rate of intestinal colonization of CRE in inpatients is high, and most strains are CRKP of type ST11-K64. These CRKP strains have both multidrug resistance and virulence characteristics, which are risks for hospital transmission.

Objective To observe the clinical efficacy of incipient diabetic nephropathy treated with Ligustrazine Hydrechloride Injection plus Candesartan Cilexetil.Methods 80 cases of incipient diabetic nephropathy were randomly divided into a treatment group and a control group,with 40 cases in each group.On the basis of treated with insulin and antidiabetic drugs,The control group was given Candesartan Cilexetii and the treatment group was given Candesartan Cilexetil together with Ligustrazine Hydrochloride Injection.Results Plasma level of ET and NO,UAER and Ua1-MG of the two groups were all reduced,while the improvement of the treatment group was better than the control group.Conclusion The combination treatment of Ligustrazine Hydrochloride Injection and Candesartan Cilexetil was an ideal one for patients with incipient diabetic nephropathy.

Objective To compare MRI wi th CT discography (CTD) for diagnostic assessment of lumbar disc disruption. Methods Paired comparative examination in 16 patients with ch ronic lower back pain without radicular pain and no disc herniation was conducte d using CT or MRI. The standard of CTD classification and positive disc was for mulated and the correlation between the induced lower back pain and dosage used in CTD was observed. Results For a total of 21 discs in the 16 patients, CTD showed the disc as type 2 in 12 discs and type 5 in 1 disc with 13 positive discs, while MRI only showed the high-intensity zone of poster ior annulus in 6 discs as the indirect sign of disc disruption and disc degenera tion in 7 discs. Conclusion CTD was the only method for showing the direct sign of disc disruption. The induced lower back pain was rel ated with the type of disc disruption. MRI can show some of the indirect signs of disc disruption and CTD can show the direct sign of disc disruption.