Risk factors of Carbapenem-resistant Enterobacterales intestinal colonization for subsequent infections in hematological patients: a retrospective case-control study.

Objective: Infections caused by Carbapenem-resistant Enterobacterales (CRE) have high treatment costs, high mortality and few effective therapeutic agents. This study aimed to determine the risk factors for progression from intestinal colonization to infection in hematological patients and the risk factors for 30-day mortality in infected patients. Methods: A retrospective case-control study was conducted in the Department of Hematology at Shandong Provincial Hospital affiliated to Shandong First Medical University from April 2018 to April 2022. Patients who developed subsequent infections were identified as the case group by electronic medical record query of patients with a positive rectal screen for CRE colonization, and patients who did not develop subsequent infections were identified as the control group by stratified random sampling. Univariate analysis and logistic regression analysis determined risk factors for developing CRE infection and risk factors for mortality in CRE-infected patients. Results: Eleven hematological patients in the study developed subsequent infections. The overall 30-day mortality rate for the 44 hematological patients in the case-control study was 11.4% (5/44). Mortality was higher in the case group than in the control group (36.5 vs. 3.0%, P = 0.0026), and septic shock was an independent risk factor for death (P = 0.024). Univariate analysis showed that risk factors for developing infections were non-steroidal immunosuppressants, serum albumin levels, and days of hospitalization. In multivariable logistic regression analysis, immunosuppressants [odds ratio (OR), 19.132; 95% confidence interval (CI), 1.349-271.420; P = 0.029] and serum albumin levels (OR, 0.817; 95% CI, 0.668-0.999; P = 0.049) were independent risk factors for developing infections. Conclusion: Our findings suggest that septic shock increases mortality in CRE-infected hematological patients. Hematological patients with CRE colonization using immunosuppressive agents and reduced serum albumin are more likely to progress to CRE infection. This study may help clinicians prevent the onset of infection early and take measures to reduce mortality rates.

An achievement has been made in establishing an induced pluripotent stem cell line (SDPHi005-A) from a healthy Chinese male donor.

Successfully transforming isolated peripheral blood mononuclear cells (PBMCs) from a healthy male into induced pluripotent stem cells (iPSCs) was achieved using non-integrating episomal vectors containing OCT4, SOX2, c-MYC, KLF4, and BCL-XL. The iPSCs exhibited a normal karyotype, expressed pluripotency markers, and demonstrated the ability to differentiate into three germ layers in vitro. This iPSC line may be employed for subsequent research purposes.

Association between alkaline phosphatase to albumin ratio and mortality among patients with sepsis.

The alkaline phosphatase-to-albumin ratio (APAR) is correlated to worse prognosis in coronary artery disease, cancer, and acute renal failure. However, the relationship between APAR and sepsis prognosis has received little research. The content of this research was to investigate the prognostic relationship between APAR and sepsis. And validate the stability of the correlation in 90-days and 1-year mortality. Retrospective cohort research was conducted basing MIMIC-IV database (version 2.0). The hazard ratio (HR) and 95% confidence interval (Cl) were computed using multivariate Cox regression analysis. In addition, plots of survival curves and subgroup analyzes were conducted. Receiver operating characteristic (ROC) curves were also used. 9741 participants were included in this investigation. The 90-days mortality was 32.8%, and the 1-year mortality was 42.0%. After controlling for confounders, the adjusted HRs (95% CI) for tertile 2 (2.2-3.8) and tertile 3 (> 3.8) were 1.37 (1.25-1.51) and 1.74 (1.58-1.91), respectively. The Kaplan-Meier curve analysis showed a higher probability of 90-days death in the higher APAR group. The area under the curve (AUC) of APAR was 0.674 and could reach 0.709 after combining the Oxford Acute Severity of Illness Score (OASIS). This study demonstrates that APAR is significantly related to bad clinical outcomes in sepsis.

Phenotypic and Molecular Characterization of K54-ST29 Hypervirulent Klebsiella pneumoniae Causing Multi-System Infection in a Patient With Diabetes.

Worldwide, hypervirulent Klebsiella pneumoniae (hvKp) is one of the leading causes of multisystem infection. Serotype K54 has also been considered as one of the hvKp-associated capsular types that are rarely reported. In this study, we reported a K54-ST29 hvKp isolated from a 58-year-old male patient with diabetes in a teaching hospital in China. The patient rapidly developed sepsis and brain abscess, with a lethal multiple-organ-system failure due to K54 hvKp infection. This K54 hvKp isolate showed high level of toxicity in a mouse infection model and was susceptible to all the tested antibiotics. The isolate was fully sequenced, and its genome was compared with the available K54 K. pneumoniae genome. We predicted 133 virulence and pathogen-related genes, including those involved in fimbriae synthesis, iron transport, and enterobactin synthesis. Sequence alignment revealed >90% similarity among seven K54 K. pneumoniae strains. Our data suggest that community-acquired infection caused by hypervirulent K54 K. pneumoniae in patients with diabetes is a concern in East Asia.

Non-integrating episomal vectors induced pluripotent stem cell line (SDPHi001-A) from a healthy female individual.

Isolated peripheral blood mononuclear cells (PBMCs) from a healthy female were successfully transformed into induced pluripotent stem cells (iPSCs) by non-integrating episomal vectors containing OCT4, SOX2, c-MYC, KLF4, and BCL-XL. The iPSCs displayed a normal karyotype, expressed pluripotency markers and could differentiate into three germ layers in vitro. This iPSC line may be subsequently used for further researches.

An Outbreak of Carbapenem-Resistant Klebsiella pneumoniae of K57 Capsular Serotype in an Emergency Intensive Care Unit of a Teaching Hospital in China.

The emergence of carbapenem-resistant hypervirulent K. pneumoniae (CR-hvKP) strains has increased the threat posed by K. pneumoniae. Here, we described an outbreak of 32 CR-hvKP isolates from the emergency intensive care unit (EICU) of a teaching hospital in China. Thirty-two CRKp isolates were collected from six patients and their surrounding environment in EICU. Antimicrobial susceptibility testing was performed using VITEK 2 compact system, E-test or the broth microdilution method. All isolates were serotyped, antimicrobial resistance genes and virulence-associated genes were screened using PCR. Multilocus sequence typing (MLST) and pulse-field gel electrophoresis (PFGE) were employed to characterize the genetic relationships among the CPKP isolates. The virulence capability of 11 CRKp isolates from six patients was evaluated through Galleria mellonella larva infection assay. PFGE showed that all 32 isolates belonged to one cluster, and MLST revealed that belonged to ST11. All isolates exhibited high resistance to ß-lactam antibiotics, quinolones, and aminoglycosides. They were susceptible to ceftazidime/averbatan, tigecycline, and colistin. All 32 isolates harbored blaKPC-2, blaSHV-11, blaTEM-1, rmtB, and qnrD. The serotype of all 32 isolates was K57. All 32 isolates contained 6 virulence genes, namely, fimH, iucB, mrkD, rmpA, uge, and wabG. Infection assays demonstrated high mortality in the Galleria mellonella model. Following measures implemented by the hospital, the outbreak was controlled. The mortality rate was 50.0%. The epidemiology of CR-hvKP should be monitored closely to detect early indications of this emerging public health threat.

Serum exosomal pregnancy zone protein as a promising biomarker in inflammatory bowel disease.

BACKGROUND: Inflammatory bowel disease (IBD) is a kind of intestinal immune dysfunction disease, and its occurrence and prevalence are on the rise worldwide. As a chronic gastrointestinal disease, its pathogenesis is still unknown. Exosomes are vesicles in various body fluids that carry a variety of substances. They can mediate intercellular communication and long-distance transport of multiple media. In this study, we investigated the protein profile of serum exosomes from healthy people and IBD patients to explore a new serological biomarker for IBD. METHODS: Initially, exosomes were extracted from serum samples, and the proteins within the exosomes were identified by label-free liquid chromatography/mass spectrometry (LC-MS/MS). Western blot and ELISA were used to assess the identified protein. To further analyze the target protein, an acute colitis mouse model was established, and exosomes in colonic tissue and serum were extracted to investigate the protein in them. RESULTS: Firstly, serum exosomes were extracted from samples, and proteins in exosomes were identified by LC-MS/MS. Through statistical analysis, we identified 633 proteins. Among these proteins, pregnancy zone protein (PZP) showed a marked difference between patients with IBD and healthy people, in that its expression level was much higher in the IBD patients This exosomal protein was associated with immunosuppressive effects. Also, the level of PZP in colon tissue exosomes and serum exosomes of acute colitis mice was significantly higher than that of the control group. CONCLUSIONS: Our findings indicated that serum exosome PZP was present at a high level in the IBD patients. Hence it might be a promising biomarker and enhance auxiliary diagnosis of IBD.

Accuracy of Xpert Carba-R Assay for the Diagnosis of Carbapenemase-Producing Organisms from Rectal Swabs and Clinical Isolates: A Meta-Analysis of Diagnostic Studies.

The Cepheid Xpert Carba-R assay has demonstrated a promising value for the detection of carbapenemase-producing organisms, but its diagnostic performance remains unclear. Studies were retrieved from Cochrane Library, EMBASE, and PubMed databases according to predetermined selection criteria. The specificity, sensitivity, negative likelihood ratio, positive likelihood ratio, and area under the summary receiver operating characteristic curves of Xpert Carba-R were analyzed by STATA version 13.0. The quality of each study was examined by Quality Assessment of Diagnostic Accuracy Studies using RevMan version 5.2. In total, 17 unique studies involving 15,972 samples met the inclusion criteria. Nine studies performed Xpert Carba-R on rectal swabs. The pooled sensitivity, specificity, and area under the curve were as follows: 0.95 (95% CI, 0.91-0.97; I2 = 90.80%), 0.99 (95% CI, 0.97-0.99; I2 = 97.17%), and 0.99 (95% CI, 0.98-1.00), respectively. The sensitivity and specificity of Xpert Carba-R in high-risk populations were 0.99 (95% CI, 0.76-1.00; I2 = 78.51%) and 0.98 (95% CI, 0.97-0.99; I2 = 84.95%), respectively. The sensitivity and specificity in low-prevalence regions were 0.96 (95% CI, 0.88-0.99; I2 = 74.58%) and 0.99 (95% CI, 0.98-0.99; I2 = 77.66%), respectively. Eight studies performed Xpert Carba-R on clinical isolates. The pooled sensitivity and specificity were 1.00 (95% CI, 0.97-1.00; I2 = 97.43%) and 0.98 (95% CI, 0.97-0.99; I2 = 55.27%), respectively. This meta-analysis indicates that Xpert Carba-R assay has excellent diagnostic accuracy for diagnosing carbapenemase-producing organisms on rectal swabs and clinical isolates, especially for high-risk populations and low-prevalence regions.

Rapid Determination of Antibiotic Resistance in Klebsiella pneumoniae by a Novel Antibiotic Susceptibility Testing Method Using SYBR Green I and Propidium Iodide Double Staining.

Due to the broad-spectrum antibiotic usage and empirical treatments, the pathogenic bacterium, Klebsiella pneumoniae, has shown extremely high detection rates at hospitals with an increasing antibiotic resistance. Therefore, rapid detection of the antibiotic resistance is urgently required and essential for effective treatments. In this study, we evaluated the performance of a newly developed method for ultra-rapid detection of antibiotic resistance in 30-60 min in K. pneumoniae by using the SYBR Green I and propidium iodide (PI) staining. A total of 100 clinical isolates were tested for antibiotic resistance using four different antibiotics (ceftriaxone, cefepime, meropenem, and ciprofloxacin). The results showed that the SYBR Green I/PI rapid antibiotic susceptibility test (AST) could reliably detect antibiotic resistance to the four drugs in 60 min, and the results were highly concordant with the conventional AST (i.e., Kirby-Bauer method and broth microdilution method) for detection of ceftriaxone, cefepime, meropenem, and ciprofloxacin resistance with a high accuracy of 99, 96, 96, and 93%, respectively. Therefore, the rapid AST established in our study helps to enable targeted therapy to save lives and reduce the empirical use of antibiotics and ultimately the health and economic burdens of antibiotic resistance.

Molecular Epidemiology and Drug Resistant Mechanism of Carbapenem-Resistant Klebsiella pneumoniae in Elderly Patients With Lower Respiratory Tract Infection.

Infection by carbapenem-resistant Klebsiella pneumoniae (CRKp) hampers the treatment of elderly patients with lower respiratory tract infection (LRTI); however, relevant data with respect to the characteristics of CRKp in elderly patients with LRTIs are limited. In the present study, K. pneumoniae isolated from elderly patients with LRTIs was collected and identified by VITEK-MS. VITEK 2 compact was used for drug sensitivity test to screen CRKps, and broth dilution method was used for drug sensitivity of tigecycline and colistin. The resistance genes, virulence genes, and serotypes of CRKps were detected via polymerase chain reaction. The homology of CRKps was analyzed via PFGE and MLST. Moreover, plasmid conjugation experiment was carried out to determine the transferability of carbapenem resistance. PCR-based replicon typing (PBRT) and S1 nuclease-PFGE were conducted for plasmid profiling. From January 2019 to August 2019, 258 elderly patients with LRTIs caused by K. pneumoniae were observed; of these, 31 (12.02%) infections were caused by CRKp strains. Majority of the patients were admitted to the intensive care unit and neurosurgery wards. Intracranial hemorrhage and pneumonia were the most common underlying diseases. Furthermore, 29 patients infected by CRKp had been exposed to various antimicrobial drugs before the positive culture. All isolates exhibited high resistance to ß-lactam antibiotics. The predominant carbapenem resistance gene was blaKPC-2, and CRKps carrying blaKPC-2 were all ST11 type. Two blaNDM-5 carrying isolates were assigned to ST307 and ST1562, respectively. Conjugative assays revealed that plasmids harboring blaNDM-5 gene were self-transmissible. Plasmid analysis suggested that two blaNDM-5 were located on a ~45 kb IncX3 type plasmid. The high incidence of CRKp in elderly patients with LRTIs indicates the urgent need for further surveillance and strict infection control measures.

Molecular characterization of Clostridioides difficile ribotype 027 in a major Chinese hospital.

BACKGROUND: The rapid spread of C. difficile 027 has become one of the leading threats of healthcare-associated infections wordwild. However, C. difficile 027 infections have rarely been reported in China. The objective of this study was to strengthen the understanding of the molecular characterizations of C. difficile 027 in China. METHODS: In this study, stool specimens from 176 suspected CDI cases were collected from 1 Jan 2018 to 30 Jun 2019. These specimens were measured by GeneXpert test and C.difficile colonies were identified and analyzed. RESULTS: There were five samples positive for tcdA, tcdB, binary toxin genes and had deletions in tcdC gene. These five Clostridioides difficile isolates belonged to ST1 and confirmed as Clostridioides difficile 027 strains by PCR ribotyping. Through using whole genome sequencing, , we found that these five strains were closely clustered into the same predominant evolutionary branch and were highly similar to C. difficile 027 strain R20291. Antimicrobial susceptibility testing result showed they were highly resistant to fluoroquinolones. CONCLUSIONS: In Our study, five C. difficile 027 isolates were identified and characterized using MLST, PCR ribotyping and whole genome sequencing. We proposed that C. difficile 027 infections are probably neglected in China. Further epidemiological studies across the country together with the introduction of routine diagnostic testing and multi-center or national level surveillance are needed to ascertain the size of this potentially significant problem.

Using Whole Genome Sequencing to Trace, Control and Characterize a Hospital Infection of IMP-4-Producing Klebsiella pneumoniae ST2253 in a Neonatal Unit in a Tertiary Hospital, China.

Background: The purpose of this study is to use whole genome sequencing (WGS) combined with epidemiological data to track a hospital infection of the carbapenem-resistant Klebsiella pneumoniae (CRKP), which affected 3 neonatal patients in the neonatal intensive care unit (NICU). Methods: The minimum inhibitory concentrations for the antimicrobial agents were determined according to the guidelines of the Clinical and Laboratory Standards Institute. Beta-lactamases were investigated using the polymerase chain reaction and DNA sequencing. The transferability of the plasmid was investigated by a conjugation experiment. The clonal relationships were evaluated using multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). WGS and single nucleotide polymorphisms (SNPs) analysis were performed on the CRKP isolates to investigate how the infection might progress. Results: Nine CRKP isolates were obtained from the NICU, seven from three patients, one from a duster cloth and one from the hand of a nurse, they all harbored blaIMP-4. Other resistance genes including blaKPC-2, blaIMP-4, blaSHV-1, blaTEM-1, blaCTX-M-15, and blaDHA-1 were also detected. PFGE analysis showed that IMP-4-producing K. pneumoniae were clonally related, and MLST assigned them to a new sequence type 2253. The SNP variations throughout the genome divided the 9 strains into three clades. Clade 1 comprised 7 strains (K1- K2 and K4-K8), whereas clade 2 and 3 consisted of only one strain each: K3 and K9, respectively.The sputum isolate K3 from patient 3 was the most distinct one differing from the other eight isolates by 239-275 SNPs. Conclusions: This is a report of using WGS to track a hospital infecion of IMP-4-producing K. pneumoniae ST2253 among neonates. Nosocomial surveillance systems are needed to limit the spread of the infection caused by these pathogens resulting from the environmental exposure in NICUs.

Genotypic and Phenotypic Characterization of bla NDM-7-Harboring IncX3 Plasmid in a ST11 Klebsiella pneumoniae Isolated From a Pediatric Patient in China.

NDM-7, a variant of New Delhi metallo-beta-lactamases (NDM), has the highest carbapenem-hydrolyzing activity. NDM-7-producing enterobacteria have been reported in many countries. In this study, we reported NDM-7 production in ST11 Klebsiella pneumoniae isolated from a boy hospitalized in the pediatric intensive care unit of a teaching hospital in China. The isolate exhibited resistance to ß-lactam antimicrobials, quinolones, and trimethoprim/sulfamethoxazole, and it harbored bla NDM- 7, bla CTX-M- 15, qnrA, qnrB, and qnrS. The serotype of the isolated K. pneumoniae was assigned as K1, and it contained three virulence genes, including kfuBC, uge, and fim. The bla NDM- 7 gene was located on a conjugative IncX3 plasmid designated as pB14NDM-7. This plasmid was fully sequenced and compared with the available bla NDM- 7-harboring IncX3 plasmids. pB14NDM-7 contained a conserved genetic context of ISkox3-umuD-IS26-ΔTn125-IS5-ΔTn125-IS3000-ΔTn2. pB14NDM-7 showed 99% nucleotide identity and the same genetic context with three bla NDM- 7-harboring IncX3 plasmids obtained from Escherichia coli in China. Our results indicate that IncX3 plasmid may contribute to the prevalence of bla NDM- 7 in China. The high prevalence of NDM variants worldwide highlights the critical need for careful monitoring and control of the rapid dissemination of bla NDM.

Epigenetics and Vascular Senescence-Potential New Therapeutic Targets?

Epigenetics is defined as the heritable alterations of gene expression without changes to the coding sequence of DNA. These alterations are mediated by processes including DNA methylation, histone modifications, and non-coding RNAs mechanisms. Vascular aging consists of both structural and functional changes in the vasculature including pathological processes that drive progression such as vascular cell senescence, inflammation, oxidation stress, and calcification. As humans age, these pathological conditions gradually accumulate, driven by epigenetic alterations, and are linked to various aging-related diseases. The development of drugs targeting a spectrum of epigenetic processes therefore offers novel treatment strategies for the targeting of age-related diseases. In our previous studies, we identified HDAC4, JMJD3, Fra-1, and GATA4 as potential pharmacological targets for regulating vascular inflammation, injury, and senescence.

Genotypic and Phenotypic Characterization of Clinical Escherichia coli Sequence Type 405 Carrying IncN2 Plasmid Harboring bla NDM-1.

We report a bla NDM-carrying ST405 Escherichia coli recovered from the abdominal fluid of a patient in Shandong, China. This strain belonged to the high-risk phylogenetic group D and carried the virulence genes, papG II, papG III, papC, and iroN. In addition to bla NDM-1, this isolate carried the quinolone resistance gene acc(6')-Ib and extended-spectrum ß-lactamase (ESBL) genes bla CTX-M-15 and bla CTX-M-14. bla NDM-1 was located on a 41 Kb IncN2 self-transmissible plasmid. The IncN2 plasmid named as pJN24NDM1 was fully sequenced and analyzed. Genome comparative analysis showed that IncN2 plasmids harboring carbapenem-resistance genes possessed conserved backbones and variable accessory regions. Phylogenetic analysis of 87 IncN plasmids based on orthologous genes indicated that 9 IncN2 plasmids fell into one phylogenetic clade, while 4 IncN3 plasmids were in two phylogenetic clades of the 74 IncN1 plasmids. The presence of IncN2 plasmids harboring bla NDM in the high-risk clone ST405 E. coli raises serious concerns for its potential of dissemination.

A Chinese cross-sectional study on depression and anxiety symptoms in patients with psoriasis vulgaris.

Previous studies have reported a higher incidence of depression and anxiety in psoriasis patients compared to the general population, which has important implications for assessment and treatment. In this study, we determined the frequency of depression and anxiety in Chinese patients with psoriasis and its relationship with disease severity and other demographic variables. The study included 208 Chinese patients with psoriasis vulgaris. The Patient Health Questionnaire (PHQ-9) and Generalized Anxiety Disorder scale (GAD-7) were used to screen for depression and anxiety. The Psoriasis Area and Severity Index (PASI) was used to assess the severity of psoriasis. Of the 208 patients included in the study, 29 patients (13.9%) were positive for moderate-to-severe depression (PHQ-9 ≥ 10) and 22 patients (10.6%) were positive for anxiety (GAD-7 ≥ 10) symptoms. Both positive stress reactors who perceived stress as an exacerbating factor of psoriasis and moderate-to-severe psoriasis were found to be positive predictors for the presence of moderate-to-severe depression or anxiety symptoms while longer duration and late onset age played a protective role. In the sample of Chinese patients with psoriasis there was a clinically significant prevalence of depression and anxiety. Our study suggests that Chinese psoriasis patients should be screened for psychiatric comorbidities.

Genotypic and Phenotypic Characterization of IncX3 Plasmid Carrying bla NDM-7 in Escherichia coli Sequence Type 167 Isolated From a Patient With Urinary Tract Infection.

Infections due to New Delhi metallo-beta lactamase (NDM)-7-producing Escherichia coli are infrequent and sporadic. In this study, we report one case of recurrent urinary tract infection caused by bla NDM-7-producing E. coli belonging to phylogenetic group A, sequence type (ST) 167. In this study, we aimed to describe the genotype and phenotype of bla NDM-7-producing E. coli in China. The isolate exhibited resistance to ß-lactam antimicrobials, trimethoprim-sulfamethoxazole, quinolones, and aminoglycosides. bla NDM-7 is located on a conjugative plasmid designated pJN05NDM-7 belonging to type IncX3. pJN05NDM-7 was fully sequenced and compared with all publicly available bla NDM-7-harboring plasmids. pJN05NDM-7 is almost identical to pKpN01-NDM7 and pKW53T, although the plasmids are geographically unrelated. The comparison of IncX3 plasmids harboring bla NDM in China showed high similarity, with genetic differences within insertion fragments. Notably, the differences in plasmids of animal and human origin were insignificant, because only one plasmid showed deletion inside the ISAba125 region compared with pJN05NDM7. Our study demonstrates that E. coli carrying IncX3 plasmids play an important role as a reservoir and in the spread of bla NDM. Further studies should be performed to control the dissemination of bla NDM among food animals.

White Matter Deficits Underlying the Impaired Consciousness Level in Patients with Disorders of Consciousness.

In this study, we aimed to (1) identify white matter (WM) deficits underlying the consciousness level in patients with disorders of consciousness (DOCs) using diffusion tensor imaging (DTI), and (2) evaluate the relationship between DTI metrics and clinical measures of the consciousness level in DOC patients. With a cohort of 8 comatose, 8 unresponsive wakefulness syndrome/vegetative state, and 14 minimally conscious state patients and 25 patient controls, we performed group comparisons of the DTI metrics in 48 core WM regions of interest (ROIs), and examined the clinical relevance using correlation analysis. We identified multiple abnormal WM ROIs in DOC patients compared with normal controls, and the DTI metrics in these ROIs were significantly correlated with clinical measures of the consciousness level. Therefore, our findings suggested that multiple WM tracts are involved in the impaired consciousness levels in DOC patients and demonstrated the clinical relevance of DTI for DOC patients.

Characteristics of carbapenemase-producing Klebsiella pneumoniae as a cause of neonatal infection in Shandong, China.

The goal of the present study was to examine the characteristics of carbapenem-resistant Klebsiella pneumoniae as a cause of neonatal infection. A total of 37 carbapenem-resistant Klebsiella pneumoniae-positive newborns hospitalized in Shandong Provincial Hospital, China between April 2011 and October 2013 were examined. Antibiotic susceptibility testing was performed using the agar dilution method and the Etest. Resistance genes were assessed by polymerase chain reaction (PCR) and sequencing. Pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST) were used to determine the genotypes and homology of these isolates. Plasmids were analyzed by PFGE and conjugation experiments. The outer membrane proteins were examined by PCR and SDS-PAGE. All of the isolates were revealed to be resistant to the third and fourth generation cephalosporins and piperacillin-tazobactam. Tigecycline, colistin, levofloxacin and amikacin were successful against all of the isolates. The antibiotic resistance rates of aztreonam, gentamicin, trimethoprim-sulfamethoxazole and fosfomycin were 13.51, 48.64, 78.38 and 86.49%, respectively. Of the 37 cases, 25 isolates (67.57%) were blaNDM-1 positive, 13 isolates (35.14%) were blaIMP-4 positive and 1 isolate (2.70%) was blaIMP-8 positive. Two isolates carried both blaNDM-1 and blaIMP-4. The isolate carrying 2-4 plasmids and blaNDM-1 and blaIMP-4 was transferable between strains. SDS-PAGE data indicated that outer membrane proteins remained present. PFGE revealed 7 distinct clusters, and MLST reported the presence of ST20, ST17, ST54, ST705 and ST290 sequences, which indicated that there was clone and plasmid spread between newborns. The main resistance mechanism of carbapenem-resistant Klebsiella pneumoniae was that the isolates expressed the carbapenemase resistance of blaNDM-1 and blaIMP-4 genes. The current study indicates that early detection of these genes may be helpful in infection prevention and control.

GenoType MTBDRplus Assay for Rapid Detection of Multidrug Resistance in Mycobacterium tuberculosis: A Meta-Analysis.

BACKGROUND: There is an urgent demand for rapid and accurate drug-susceptibility testing for the detection of multidrug-resistant tuberculosis. The GenoType MTBDRplus assay is a promising molecular kit designed for rapid identification of resistance to first-line anti-tuberculosis drugs, isoniazid and rifampicin. The aim of this meta-analysis was to evaluate the diagnostic accuracy of GenoType MTBDRplus in detecting drug resistance to isoniazid and rifampicin in comparison with the conventional drug susceptibility tests. METHODS: We searched PubMed, EMBASE, and Cochrane Library databases to identify studies according to predetermined criteria. A total of 40 studies were included in the meta-analysis. QUADAS-2 was used to assess the quality of included studies with RevMan 5.2. STATA 13.0 software was used to analyze the tests for sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the summary receiver operating characteristic curves. Heterogeneity in accuracy measures was tested with Spearman correlation coefficient and Chi-square. RESULTS: Patient selection bias was observed in most studies. The pooled sensitivity (95% confidence intervals were 0.91 (0.88-0.94) for isoniazid, 0.96 (0.95-0.97) for rifampicin, and 0.91(0.86-0.94) for multidrug-resistance. The pooled specificity (95% CI) was 0.99 (0.98-0.99) for isoniazid, 0.98 (0.97-0.99) for rifampicin and 0.99 (0.99-1.00) for multidrug-resistance, respectively. The area under the summary receiver operating characteristic curves ranged from 0.99 to 1.00. CONCLUSION: This meta-analysis determined that GenoType MTBDRplus had good accuracy for rapid detection of drug resistance to isoniazid and/or rifampicin of M. tuberculosis. MTBDRplus method might be a good alternative to conventional drug susceptibility tests in clinical practice.