Bacteriologic profile, antibiotics resistance pattern, and outcomes of patients admitted to Lancet General Hospital from June 2022 to June 2023: A retrospective cohort study

Background Prior studies indicated increased antimicrobial resistance in Ethiopia, with related health, economic, and environmental costs. Knowing an institutions and population microbiologic profile allows for proper antibi-otic treatment, which substantially impact patients' outcomes such as healthcare related costs, morbidity, and mortality. The current study assessed the bacteriologic profile, resistance pattern, and treatment outcome in Lancet General Hospital. Method A retrospective cohort study on the bacteriologic profile, antibiotics resistance pattern, and outcome of patients was done on 128 eligible patients who were admitted to Lancet General Hospital from June 2022 to June 2023. Data from all hospitalized patients with culture-confirmed infection were analyzed. SPSS version 26.0 was used to analyze the data. Association between independent and dependent variables was analyzed using binary logistic regression model. Results Gram-negative bacteria were recovered in 77% of the cases. Extended-spectrum beta-lactamase producing Enterobacteriaceae was found in 37.5% (54) isolates and carbapenem resistant bacteria were identified in 27.8% of patients. In-hospital mortality from multidrug resistant bacterial infection was 14.8%. Age ≥ 65 years, presence of septic shock, and presence of carbapenem-resistant bacteria were independently associated with in-creased in-hospital mortality. Conclusion High number of resistant microorganisms was isolated, and increased mortality was documented from infections caused by carbapenem-resistant bacteria. Multi-center studies should be done to determine the extent of resistant organisms in health facilities throughout the country. epidemiology, and the findings should be factored into clinical decision making and program design for disease prevention, screening, and treatment. It also calls for further prospective research to learn more about the conditions in the context of additional relevant personal and clinical characteristics

Efficacy and safety analysis of tigecycline and polymyxin B in the treatment of carbapenem-resistant enterobacteriaceae pneumonia in critically ill patients / 中国临床药理学与治疗学

AIM: To compare the efficacy and safety of tigecycline with polymyxin B in the treatment of carbapenem resistant enterobacteriaceae (CRE) pneumonia in critically ill patients. METHODS: A retrospective analysis was performed on the clinical data of patients with CRE pneumonia who received tigecycline or polymyxin B therapy from January 1, 2018 to Jun 30, 2023 in the Intensive Care Unit (ICU). Primary outcomes included the 28-day all-cause mortality and clinical cure rate within 28days. Secondary outcomes included the ICU mortality, in-hospital mortality, the length of hospital stay and ICU stay, microbial eradication, duration of mechanical ventilation. Independent predictors affecting 28-day clinical cure rate were tested using Cox regression analyses. RESULTS: A total of 83 eligible patients were included in the final analysis after propensity score matching, 54 in the tigecycline group and 29 in the polymyxin B group. The 28-day all-cause mortality was 31.5% (17/54) in the tigecycline group and 37.9% (11/29) in the polymyxin B group, the difference was not statistically significant (P=0.554); the clinical cure rate was 63% (34/ 54) in the tigecycline group, which was significantly higher than that of the polymyxin B group of 34.5% (10/29) (P = 0.013). There were no statistical differences between the two groups in terms of secondary outcomes. Multivariate logistic regression analysis found that the use of tigecycline was an independent predictor of the 28-day clinical cure rate (HR 2.083, 95%CI 1.018-4.263, P = 0.045). However, activated partial thromboplastin time (APTT) and prothrombin time (PT) were significantly prolonged in the tigecycline group compared with the polymyxin B group (P=0.047; P=0.027), and fibrinogen (FIB) was significantly decreased (P < 0.001) after drug administration. CONCLUSION: There was no significant difference in 28-day all-cause mortality between the tigecycline and polymyxin groups; tigecycline might be associated with a higher 28-day clinical cure rate compared with polymyxin B. It should be noted that tigecycline may increase the risk of coagulation abnormalities.

Establishment of UPLC-MS/MS method for the determination of plasma concentration of three common carbapenem antibiotics / 中国药房

OBJECTIVE To establish a UPLC-MS/MS method for the determination of plasma concentration of three carbapenem antibiotics， i.e. ertapenem （ETP）， imipenem （IPM） and meropenem （MEM）. METHODS After protein precipitation with methanol， the plasma samples were separated by ACQUITY UPLC BEH C18 column （2.1 mm×50 mm， 1.7 μm） using stable isotopes of three antibiotics （ETP-D4， IPM-D4， MEM-D6） as the internal standard. The mobile phases were 98% acetonitrile +2% water +0.1% formic acid and 98% water +2% acetonitrile +0.1% formic acid， by gradient elution. The flow rate was 0.3 mL/min and the column temperature was 40 ℃. Scanning analysis was performed in the positive ion and multiple reaction monitoring mode. RESULTS The method had good specificity， good linearity （r2≥0.993） in the range of 0.2-200， 0.1-100 and 0.1-100 μg/mL of ETP， IPM and MEM， and good intra-batch and inter-batch precision and accuracy （all RE≤5.14%， all RSD≤11.15%）， the matrix effect and extraction recovery were consistent （RSD≤12.99%）. CONCLUSIONS This study establishes the UPLC-MS/MS method to simultaneously quantify the plasma concentration of ETP， IPM and MEM. The method has the advantages of simple pretreatment， short detection time and small sample quantity to meet clinical requirement.

Construction of a risk prediction model for bloodstream infection induced by carbapenem-resistant Klebsiella pneumoniae / 中国药房

OBJECTIVE To construct a risk prediction model for bloodstream infection （BSI） induced by carbapenem-resistant Klebsiella pneumoniae （CRKP）. METHODS Retrospective analysis was conducted for clinical data from 253 patients with BSI induced by K. pneumoniae in the First Hospital of Qinhuangdao from January 2019 to June 2022. Patients admitted from January 2019 to December 2021 were selected as the model group （n＝223）， and patients admitted from January 2022 to June 2022 were selected as the validation group （n＝30）. The model group was divided into the CRKP subgroup （n＝56） and the carbapenem- sensitive K. pneumoniae （CSKP） subgroup （n＝167） based on whether CRKP was detected or not. The univariate and multivariate Logistic analyses were performed on basic information such as gender， age and comorbid underlying diseases in two subgroups of patients； independent risk factors were screened for CRKP-induced BSI， and a risk prediction model was constructed. The established model was verified with patients in the validation group as the target. RESULTS Admissioning to intensive care unit （ICU）， use of immunosuppressants， empirical use of carbapenems and empirical use of antibiotics against Gram-positive coccus were independent risk factors of CRKP-induced BSI （ORs were 3.749， 3.074， 2.909， 9.419， 95%CIs were 1.639-8.572， 1.292- 7.312， 1.180-7.717， 2.877-30.840， P＜0.05）. Based on this， a risk prediction model was established with a P value of 0.365. The AUC of the receiver operating characteristic （ROC） curve of the model was 0.848 [95%CI （0.779， 0.916）， P＜0.001]， and the critical score was 6.5. In the validation group， the overall accuracy of the prediction under the model was 86.67%， and the AUC of ROC curve was 0.926 [95%CI （0.809， 1.000]， P＜0.001]. CONCLUSIONS Admission to ICU， use of immunosuppressants， empirical use of carbapenems and empirical use of antibiotics against Gram-positive coccus are independent risk factors of CRKP- induced BSI. The CRKP-induced BSI risk prediction model based on the above factors has good prediction accuracy.

Uso de ceftazidima-avibactam en una recién nacida prematura con infección urinaria bacteriémica por Klebsiella pneumoniae productora de carbapenemasa

Los recién nacidos tienen un alto riesgo de morbimortalidad asociada a infecciones durante su estancia en unidades de cuidado intensivo neonatal, a lo que se asocia un aumento progresivo de infecciones por microorganismos multi-resistentes que requiere el uso de nuevos antimicrobianos. Presentamos el caso de una recién nacida de pretérmino de 36 semanas que cursó con una infección del tracto urinario bacteriémica por Klebsiella pneumoniae productora de carbapenemasa tratada de forma efectiva con 14 días de cefazi- dima-avibactam, sin efectos adversos observados. Según nuestro conocimiento, este es el primer caso reportado en nuestro país del uso de este antimicrobiano en población neonatal. Se necesita más información sobre la eficacia y seguridad de ceftazidima-avibactam en este grupo de pacientes.

Neonates are high risk patients regarding morbimortality secondary to infections during their neonatal intensive care unit stay, which is associated to a progressive increase in the report of multidrug resistant organism infections, that require the use of new antimicrobial. We report the case of a 36-week preterm with an urinary tract infection with bacteriemia caused by carbapenemase- producing Klebsiella pneumoniae treated effectively with 14 day of ceftazidime-avibactam, without observed adverse effects. To our knowledge, this is the first case report in our country of the use of this antibiotic in neonatal population. More information is needed regarding efficacy and safety of ceftazidime-avibactam in this group of patients.

Risk factors for extended-spectrum beta-lactamase- and carbapenem- resistant Enterobacteriaceae in patients with urinary tract infection from a tertiary care hospital

Background: Urinary tract infection (UTI) is a common health problem in both community and nosocomial settings. However, the predisposing factors which are responsible for production of extended spectrum beta-lactamase (ESBL) and carbapenem-resistant Enterobacteriaceae makes the treatment option narrow and cause multidrug resistance. Aim and Objectives: This study demonstrate various risk factors associated with multidrug resistance in Enterobacteriaceae from UTI at tertiary care center in Gujarat. Material and Methods: A retrospective observational study was conducted at a tertiary-care hospital. Urine samples were received from various departments and outpatient department (OPD). Organisms from Enterobacteriaceae group were isolated and identified by various biochemical methods. ESBL and Carbapenemase producing organisms were then processed for Antibiotic susceptibility test as per CLSI guideline. Results: A total of 196 Enterobacteriaceae organisms were isolated from processed urine samples of tertiary care Hospitals. The most prevalent in people aged 45–65 years (36%) followed by those aged 17–30 (22%) years. UTI due to ESBL and Carbapenemase producer are more isolated in female (28%, 11%) as compare to male (16%, 6%). Indoor patients had higher prevalence of ESBL (29%) and carbapenemases (10%) isolation compare to OPD patient (ESBL-15%, Carbapenemases-7%) and among them most common ward was medicine department. The most common predisposing factor was catheterization followed by diabetes mellitus and obstructive uropathy. Conclusion: High prevalence of ESBL and Carbapenemase producing Enterobacteriaceae is found in Indoor patients than OPD patients. Most of these patients are from Medicine department. Catheterization is the most common risk factor associated with ESBL and carbapenemase producing organism.

Detection and correlation of antimicrobial resistance pattern in Enterobacteriaceae from UTI patients in GMERS Medical College, Gujarat

Background: Bacterial resistance to antibiotics is a growing public health threat worldwide. The increasing rate of antimicrobial resistance among bacterial pathogens causing both hospital- and community-acquired infections is a serious threat to public health world-wide. This inappropriate and non-judicious usage of antibiotics has resulted in the development of worldwide antibiotic resistance in bacteria, leading to the emergence of multi-resistant strains of bacterial pathogens. This study focuses on the prevalence of antibiotic resistance in the Enterobacteriaceae group of organisms in urine samples and also detects various methods of antibiotic resistance. Antibiotic resistance detection may be useful for epidemiological and research purposes, as well as for preventing the spread of drug-resistant organisms within hospitals through good infection control practices. Aims and Objectives: The aim of the study was to detect occurrence of ?-lactamases, extended-spectrum beta-lactamases (ESBL) and Carbapenemase by phenotypic methods in Enterobacteriaceae from urine samples along with pattern of antibiotic resistance for various antibiotics in them. Materials and Methods: A descriptive study was conducted at a tertiary-care hospital. Testing of ESBL and carbapenemase production detection done according to CLSI (M100) guideline by the Kirby-Bauer disk diffusion method, combination disc diffusion test, and modified Carbapenem inactivation method. Results: A total of 220 Enterobacteriaceae organisms were isolated from processed urine samples of tertiary care Hospitals. Rate of cephalosporin resistance in ESBL and carbapenem-resistant Enterobacteriaceae (CRE) is more than 90% while in non-ESBL more than 70% and in non-CRE 75–80%. Carbapenem resistance in ESBL and non-ESBL is the same. Resistance to fluoroquinolone group, Aminoglycoside group, and Cotrimoxazole and Tetracycline group of antibiotics were more noticed in ESBL and carbapenemase producing organisms. In our study, fosfomycin and Nitrofurantoin are effective treatment in case of ESBL and CRE producing organism. Conclusion: The ESBL and Carbapenemase producing isolates were multi-drug resistant making therapeutic choices limited. Fosfomycin and Nitrofurantoin are effective treatment in multidrug resistance urinary tract infection.

Molecular epidemiology of clinical isolation of carbapenem-resistant Enterobacterales and application of carbapenemase inhibitor enhancement test / 中南大学学报(医学版)

OBJECTIVES@#The prevalence of carbapenem-resistant Enterobacterales (CRE) presents a significant challenge in clinical anti-infective treatment. This study aims to investigate drug resistance and the molecular epidemiological characteristics of CRE in our area. Additionally, we seek to evaluate practicality of utilizing carbapenemase inhibitor enhancement test in clinical laboratory.@*METHODS@#Non-repeated CREs isolated from clinical specimens at Xiangya Hospital, Central South University, were collected. Minimum inhibitory concentration (MIC) combined with Kirby-Bauer (KB) assay was used to detect the drug susceptibility of the strains, and 13 carbapenemase-producing genes were detected by PCR. The phenotype of 126 strains of carbapenemase-producing Enterobacterales identified by PCR was detected by the carbapenemase inhibitor enhancement test to understand the agreement between the method and the gold standard PCR results.@*RESULTS@#Among 704 CRE strains examined, we observed significant drug resistance in 501 strains dentified as carbapenemase-producing Enterobacterales (CPE). Klebsiella pneumoniae was the predominant CPE strain, followed by Enterobacter cloacae and Escherichia coli. A total of 9 carbapenemase types were detected, including Klebsiella pneumoniae carbapenemase (KPC), New Delhi metallo-β-lactamase (NDM), Verona integron- encoded metallo-β-lactamases (VIM), imipenemase (IMP), oxacillinase-48 (OXA-48), and rare imipenem-hydrolyzing β-lactamase (IMI), adelaide imipenemase (AIM), Bicêtre carbapenemase (BIC), and guiana extended-spectrum β-lactamase (GES). The detection rate of KPC serine carbapenemase was 61.7% (309/501). The carbapenemase inhibitor enhancement test exhibited a 100% consistency rate for the strains producing Class A serine carbapenemase and/or Class B metallo-β-lactamases.@*CONCLUSIONS@#CRE strains in Changsha, Hunan, China, are wide distribution and exhibit carbapenemase production. The main mechanism of carbapenem resistance in these bacterias is predominatly attributed to the production of KPC serine carbapenemase. The presence of GES and IMI genes carried by Enterobacterales has been detected for the first time in this region. The carbapenemase inhibitor enhancement test has been proven to be an accurate method for detecting CRE producing Class A serine carbapenemase and/or Class B metallo-β-lactamases. This method offers simpicity of operation and ease of results interpretation, making it weel-suited meeting the clinical microbiology laboratory's reguirements for the detection of serine carbapenemase and metallo-β-lactamases.

Effects of overexpression of carbapenem OXA-48 on drug resistance,adaptability of bacterial strain and Toll-like receptor signaling pathway of host cell / 中国生物制品学杂志

@#Objective To investigate the effects of overexpression of OXA-48 on drug resistance,adaptability of bacterial strain and Toll-like receptor(TLR)signaling pathway of host cells. Methods The recombinant plasmid pET32a(+)-OXA-48was transformed into E.coli BL21(DE3),and the recombinant strain pET32a(+)-OXA-48-BL21(DE3)was identified by colony PCR and sequencing. Taking A_(600)(0. 3,0. 5 and 0. 7),IPTG final concentration(0. 4,0. 6 and 0. 8mmol/L)and induction time(2,4 and 6 h)as variables and mRNA transcription level as response value,an orthogonal experiment with three factors and three levels was designed to optimize the induced expression conditions of the plasmid. The drug resistance of recombinant strain pET32a(+)-OXA-48-BL21(DE3)to Imipenem(IPM),Meropenem(MEM),Ceftriaxone(CRO)and Cefepime(FEP)was detected by disk diffusion method;The adaptability was detected by biofilm formation test and serum resistance test. Mouse alveolar macrophages(MH-S)were infected with pET32a(+)-OXA-48-BL21(DE3),pET32a(+)-BL21(DE3)and E.coli BL21(DE3)strains,respectively. The mRNA transcription levels of TLR2,TLR4 and NF-кB(p65)genes were detected by qRT-PCR method,and the expressions of Interleukin-6(IL-6),IL-10,tumor necrosis factor-α(TNF-α)and transforming growth factor-β(TGF-β)were detected by ELISA. Results The recombinant strain pET32a(+)-OXA-48-BL21(DE3)was constructed correctly as identified by colony PCR and sequencing. The optimum induction conditions were as follows:A_(600)of 0. 3,IPTG final concentration of 0. 6 mmol/L and induction time of 2 h. Compared with pET32a(+)-BL21(DE3)strain,the resistance of recombinant strain pET32a(+)-OXA-48-BL21(DE3)to IPM,MEM,CRO and FEP significantly decreased(t = 7. 14～22. 32,P < 0. 05),the biofilm formed significantly increased(t = 15. 69,P < 0. 05),and the survival rate in serum significantly increased(t = 10. 60,P < 0. 05);The mRNA transcription level of TLR2 gene in MH-S cells infected with pET32a(+)-OXA-48-BL21(DE3)significantly increased 24 h after infection(t = 5. 77,P < 0. 05),while the mRNA transcription level of TLR4 and NF-кB(p65)genes(t = 3. 71～10. 06,P < 0. 05)and the expression level of IL-6 significantly increased 12 and 24 h after infection. Compared with the normal group,the expression of IL-6and TNF-α in MH-S cells infected with pET32a(+)-OXA-48-BL21(DE3)increased significantly at 6,12 and 24 h after infection(t = 7. 90 ～ 13. 44 and 5. 40～6. 32 respectively,each P < 0. 01),while the expression of IL-10 decreased significantly(t = 3. 15～4. 08,each P < 0. 05). There was no significant difference in the expression of TGF-β(t = 0. 013～1. 41,each P > 0. 05). The expression of IL-6 was significantly higher than that in pET32a(+)-BL21(DE3)group at 12 and 24 h after infection(t = 2. 92 and 3. 79 respectively,each P < 0.05) Conclusion Overexpression of OXA-48 can reduce bacterial drug resistance,improve bacterial adaptability and the transcription level of factors related to TLR signaling pathway in host cells,and affect the expression level of downstream cytokines in host cells.

Epidemiological characteristics of carbapenem-resistant Klebsiella pneumoniae infection in adult inpatients / 公共卫生与预防医学

Objective To analyze the epidemiological characteristics of carbapenem-resistant Klebsiella pneumoniae (CRKP) in adult inpatients, and to provide a theoretical basis for the diagnosis and treatment of CRKP. Methods A total of 753 hospitalized patients with Klebsiella pneumoniae (KPN) infection in our hospital from 2017 to 2021 were selected as the investigation subjects. According to the sensitivity to carbapenem drugs, the patients were divided into carbapenem sensitive Klebsiella pneumoniae (CSKP) group (n=638) and CRKP group (n=115). The age, gender, department distribution, underlying diseases, length of hospital stay, use of antibiotics and other clinical data of all subjects were analyzed by self-made survey scale of our hospital. Univariate analysis and logistic regression analysis were used to analyze the risk factors of CRKP nosocomial infection in adult inpatients. Results Among of 753 KPN patients, 115 cases (15.27%) were detected with CRKP, including 87 males and 28 females. The detection rate of CRKP in different age groups was significantly different (P60 years was significantly higher than that in the age group of 41-60 years, 21-40 years, and 16-20 years (P2 value =0.725, P>0.05). CRKP strains were mainly isolated from oral and maxillofacial surgery (19.13%), infection department (15.65%), geriatric department (15.65%), and ICU (14.78%). The detection rate of CRKP in different pathogenic bacteria samples was different, including sputum (19.40%), urine (15.43%) and blood (12.58%), with statistically significant difference (P<0.05) The respiratory tract sputum specimens were all expectoration. There were significant differences in age, gender, use of carbapenems ≥7 days, invasive procedures, use of antibiotics ≥2 kinds, use of antibiotics ≥14 days, and use of enzyme inhibitors ≥7 days between the CSKP group and the CRKP group (P<0.05). Antimicrobial application time ≥14 days (OR=5.412), invasive operation (OR=6.431), and carbapenem use ≥7 days (OR=5.417) were the risk factors for CRKP nosocomial infection in adult inpatients (P<0.05). Conclusion Nosocomial infection of CRKP occurs mostly in elderly ICU patients. Intervention measures should be given to adult inpatients who have used antibiotics for ≥14 days, invasive procedures, and carbapenem antibiotics for ≥7 days, which can reduce the risk of CRKP infection in inpatients.

Mechanism of polymyxin resistance related to lipopolysaccharide modification in carbapenem-resistant Klebsiella pneumoniae / 中华微生物学和免疫学杂志

Objective:To investigate the mechanism of polymyxin resistance related to lipopolysaccharide modification in carbapenem-resistant Klebsiella pneumoniae (CRKP). Methods:Plasmid-mediated drug resistance genes in seven CRKP strains were detected by conjugation assay and mcr gene detection. The expression of polymyxin resistance-related genes was measured using quantitative real-time PCR. The complete genomes of CRKP strains were sequenced. Silver staining and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) were performed to analyze the changes in lipopolysaccharide (LPS). Results:The seven CRKP strains were negative for mcr genes and the results of conjugation assay were also negative. Moreover, no mobile genetic elements related to drug resistance were detected. Compared with wild-type strain, all seven CRKP strains that were resistant to polymyxin showed increased expression of pmrA, pmrB and pmrC genes at the transcriptional level; six showed increased expression of phoP/ phoQ genes; three showed decreased expression of crrA/ crrB genes; four showed decreased expression of mgrB gene. The missense mutation sites in drug-resistant strains were mainly in KPHS_09430, KPHS_35900, KPHS_39520 and KPHS_52420. IS Kpn14 insertion sequence was detected in CRKP-6 strain. MALDI-TOF-MS reveals the modification of natural lipid A with L-Ara4N in CRKP LPS. Conclusions:LPS modification induced by chromosome-mediated mutation in the two-component regulatory system was the main molecular mechanism of polymyxin resistance in CRKP isolates in this study. Effects of the mutation in the two-component system on polymyxin resistance varied in different strains.

Dissemination mechanism of blaKPC-2 among carbapenem-resistant Klebsiella pneumoniae strains / 中华微生物学和免疫学杂志

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is highly prevalent and poses a great health challenge due to the lack of effective treatments. Klebsiella pneumoniae carbapenemase-2 (KPC-2), encoded by blaKPC-2 gene, is one of the major contributors to carbapenem resistance in CRKP. In China and other Asian regions, Tn1721 and plasmid IncFⅡ are the main vectors for blaKPC-2 transfer between Kpn ST11 strains, which lack clustered regularly interspaced short palindromic repeats (CRISPR) and restriction-modification (R-M) systems. The structure of transposons has a significant impact on the transposition frequency of blaKPC-2, which may be related to the different transposition patterns of transposons. The prevalence advantage of blaKPC-2 in Kpn ST11 strains is highly associated with the immune deficiency in Kpn ST11. By acquiring a re-engineered CRISPR-Cas3 system via conjugation, the high-risk IncFⅡ plasmid can be successfully cleaved and ST11 CRKP can regain antibiotic sensitivity, which provides a promising approach for clinical treatment and prevention of CRKP.

The level and significance of CD64 index, matrix metalloproteinase-9 and serum amyloid A in peripheral blood of patients with severe carbapenem resistant Enterobacteriaceae infection / 中国医师杂志

Objective:To investigate the level and significance of CD64 index, matrix metalloproteinase-9 (MMP-9) and serum amyloid A (SAA) in peripheral blood of patients with severe carbapenem resistant Enterobacteriaceae (CRE) infection.Methods:A total of 61 patients with severe CRE infection who were admitted to the neurosurgery department of Kashgar First People′s Hospital from January 2019 to January 2022 were selected as the CRE group, and 100 patients with severe carbapenem sensitive Enterobacteriaceae (CSE) infection were selected as the CSE group. The difference in clinical data between the two groups was compared, and the difference in clinical data between the dead and surviving patients in the CRE group was compared. The value of CD64 index, MMP-9 and SAA in differential diagnosis of CRE was analyzed. Logistic regression was used to analyze the influencing factors of prognosis in patients with CRE infection.Results:The age, hypertension, lung disease, liver and kidney disease, comorbidities≥2, antibiotic use≥2 combinations, antibiotic use time>10 days, proportion of carbapenem use, CD64 index, MMP-9, and SAA of the CRE group patients were significantly higher than those of the CSE group patients (all P<0.05). The area under the receiver operating characteristic (ROC) curve for CD64 index, MMP-9, and SAA differential diagnosis of CRE was 0.857, 0.701, and 0.655, respectively (all P<0.05). In the CRE group, the age , the score of Acute Physiological and Chronic Health Status Ⅱ (APACHE Ⅱ) score at admission, diabetes, liver and kidney diseases, comorbidities≥2, the proportion of carbapenems, CD64 index, MMP-9 and SAA of dead patients were significantly higher than those of survivors (all P<0.05). Logistic regression analysis showed that age, APACHE Ⅱ score at admission, comorbidities≥2, CD64 index, MMP-9, and SAA were influencing factors for the prognosis of severe CRE patients (all P<0.05). Conclusions:The peripheral blood CD64 index, MMP-9, and SAA have certain application value in the diagnosis of neurological severe CRE infection, and are also influencing factors for the prognosis of CRE infected patients.

Update on the prevention and treatment of neonatal Carbapenem-resistant Klebsiella pneumoniae / 中国小儿急救医学

In recent years, the use of broad-spectrum antibiotics in clinical practice has led to an increase in the detection of Carbapenem-resistant Klebsiella pneumoniae(CrKP)in neonatal intensive care units.CrKP infection in newborns usually lacks specific clinical manifestations and can lead to bacteremia, meningitis and abdominal infections, which can be life-threatening.Combination of carbapenem antibiotics or newer drugs such as ceftazidime/avibactam, tigecycline and polymyxin are currently effective treatment options for CrKP infection in neonates.In addition to rational drug use, strict antimicrobial stewardship, hospital infection prevention and control measures are needed to reduce the colonisation and spread of CrKP in the neonatal ward.

Real-world study of ceftazidime-avibactam in the treatment of multidrug-resistant gram-negative bacterial infections / 中国临床药理学与治疗学

AIM: To describe and evaluate the clinical characteristics, treatment management and clinical outcomes of ceftazidime-avibactam (CZA) in the treatment of patients with multidrug-resistant gram-negative bacterial (MDR-GNB) infections. METHODS: A retrospective cohort study was performed on patients hospitalized in the Affiliated Hospital of Xuzhou Medical University from September 2019 to December 2021. Adult patients who received CZA for ≥ 72 hours consecutively were eligible for inclusion. The primary outcome was clinical failure, defined as a composite of 30-day all-cause mortality, microbiological failure and / or failure to resolve or improve signs and symptoms of infection during treatment with CZA. RESULTS: A total of 198 patients with MDR-GNB infections were described and evaluated, including 132 in the carbapenem-resistant Enterobatceriaceae (CRE) cohort and 66 in the Pseudomonas spp. cohort. The main infection sites were lung infection (92.42%), abdominal infection (10.61%), and intracranial infection (10.61%), among which 63 patients (31.82%) were positive for blood culture. Clinical failure, 30-day all-cause mortality and microbiological failure occurred in 61 (30.81%), 33(16.67%) and 11(5.56%) patients, respectively. Body mass index (BMI), acute physiology and chronic health evaluation scoring system (APACHE Ⅱ) and polymicrobial infections were positively associated with clinical outcome failureadjusted OR 1.109, 95%CI 1.017, 1.209; adjusted OR 1.071, 95%CI 1.015, 1.129; adjusted OR 2.844, 95%CI 1.391, 5.814, however, initiation of CZA within 48 hours of admission was protective (adjusted OR 0.424, 95%CI 0.205, 0.879). A total of 15 patients had adverse reactions possibly related to CZA, including 2 cases of rash, 6 cases of nausea and vomiting, and 7 cases of antibiotic-related diarrhea. CONCLUSION: CZA can be used to treat infections caused by a range of MDR-GNB, including Pseudomonas spp. and CRE.

Isolation of Leclercia adecarboxylata Producing Carbapenemases in A Newborn Female / 生物医学与环境科学（英文）

Leclercia adecarboxylata is a Gram-negative bacterium belonging to the Enterobacteriaceae family. To our knowledge, this is the first report of a carbapenem-resistant L. adecarboxylata strain isolated from a healthy newborn. The L. adecarboxylata strain isolated in this study carried four plasmids that may serve as reservoirs for antibiotic resistance genes. Plasmids 2 and 4 did not harbor any antimicrobial resistance genes. Plasmid 3 is a novel plasmid containing three resistance genes. The bla IMP gene harbored in the strain was most similar to bla IMP-79 at the nucleotide level, with a similarity of 99.4% (737/741). This case highlights the importance of considering L. adecarboxylata as a potential cause of infections in children.

Screening and clinical significance of intestinal colonization of carbapenem-resistant Enterobacteriaceae (CRE) in patients before haploidentical hematopoietic stem cell transplantation / 中国输血杂志

【Objective】 To investigate the situation of carbapenem-resistant Enterobacteriaceae(CRE) colonization in patients undergoing haploidentical hematopoietic stem cell transplantation (haplo-HSCT). 【Methods】 A total of 241 consecutive patients who underwent haplo-HSCT in the First Affiliated Hospital of Soochow University from June 1, 2021 to June 1, 2022 were enrolled. Anal swab screening was performed within 48 hours of admission and blood cultures were taken when the patient developed fever. Univariate and multivariate analysis were used to analyze the colonization rate, distribution, risk factors and the correlation between CRE colonization and post-transplant bloodstream infection(BSI). 【Results】 Among 241 patients with haplo-HSCT, there were 90 cases in CRE colonization positive group, with a colonization rate of 37.3% (90/241). Multivariate logistic regression analysis showed that sex (OR 2.42, 95% CI 1.38-4.22, P<0.05) and history of infection within 30 days before transplantation (OR 3.37, 95% CI 1.59-7.17, P<0.05) may be independent risk factors for CRE intestinal colonization. Of the 95 CRE strains, the top five species were carbapenem-resistant Klebsiella pneumoniae (38/95, 40.0%), carbapenem-resistant Escherichia coli (29/95, 30.5%), carbapenem-resistant Enterobacter cloacae (13/95, 13.6%), carbapenem-resistant Klebsiella acidophilus (6/95, 6.3%) and carbapenem-resistant Proteus mirabilis (3/95, 3.1%). The incidence of post-transplant BSI was 12.0% (29/241) in the CRE-colonized group and 3.3% (8/241) in the non-colonized group. In the colonization group, 100% of the pathogens of BSI were identical with those of CRE colonization. 【Conclusion】 Bacterial culture of anal swab during haplo-HSCT is helpful for detection of CRE colonization in intestinal tract, which provides some clinical basis for active monitoring of key flora, prevention and control of infection.

Clinical observation of polymyxin B in the treatment of CRKP-BSI in patients with hematological malignancies / 中国药房

OBJECTIVE To analyze the efficacy and safety of polymyxin B in the treatment of carbapenem-resistant Klebsiella pneumoniae （CRKP）-bloodstream infection （BSI） in patients with hematologic malignancies. METHODS The medical records of patients with hematologic malignancies with CRKP-BSI who received polymyxin B for at least 3 days in our hospital from September 2019 to June 2021 were retrospectively analyzed. All patients were initially treated with a triple therapy namely polymyxin B+tigecycline+carbapenems for anti-infection therapy. RESULTS A total of 10 patients were enrolled as the study subjects. Eleven strains of CRKP were cultured in blood， including 10 strains of CRKP produced Klebsiella pneumoniae carbapenemase（KPC） and 1 strain of CRKP produced both KPC and metal-beta-lactamase； 9 strains were sensitive to colistin， 7 strains were sensitive to tigecycline， 5 strains were sensitive to amikacin and 2 strains were sensitive to compound sulfamethoxazole. All patients were accompanied by neutropenia， with an average duration of （14.1±6.4） days. They were all characterized by fever， chills and fatigue. After treatment， 6 patients were cured and discharged， 4 patients died of ineffective treatment of septic shock. No serious adverse events related to polymyxin B occurred in all patients. CONCLUSIONS Polymyxin B can be used as a therapeutic drug for CRKP-BSI in patients with hematological malignancies. No serious adverse event related to polymyxin B occurs during the treatment.

Efficacy and safety of ceftazidime and avibactam sodium in the treatment of carbapenem-resistant organism infection / 中国药房

OBJECTIVE To observe the efficacy and safety of ceftazidime and avibactam sodium （CAZ/AVI） in the treatment of carbapenem-resistant organism （CRO） infection. METHODS The information of patients with CRO infection admitted to the Second Affiliated Hospital of Soochow University from September 2019 to March 2022 was collected， and the patients were retrospectively divided into observation group （48 cases） and control group （48 cases） according to the treatment plan. The control group was given Polycolistin B sulfate for injection intravenously at a dose of 500 000 U every 12 hours； no dose adjustment was performed in patients with renal insufficiency or receiving continuous renal replacement therapy （CRRT）. The observation group was given continuous micropump of CAZ/AVI for injection intravenously at a dose of 2.5 g every 8 hours for 2 continous hours； among them， the patients with renal insufficiency received an adjusted dose based on creatinine clearance， and no dose adjustment was performed in patients receiving CRRT. The clinical efficacy and microbiological efficacy as well as body temperature， white blood cell （WBC）， C-reactive protein （CRP） and procalcitonin （PCT） before and after treatment were compared between 2 groups. The prognosis and the occurrence of adverse drug reactions were recorded. The factors influencing the clinical efficacy were screened by Logistic regression analysis. RESULTS The effective rate and microbial clearance rate of the observation group were significantly higher than the control group （P＜0.05）. After treatment， body temperature， PCT and CRP of 2 groups were significantly lower than before treatment， and CRP of the observation group was significantly lower than the control （No.SDFEYJLC2105） group （P＜0.05）. There was no statistically significant differencebetween the two groups in terms of rehabilitation discharge rate， the proportion of patients transferred to general wards，the proportion of dead patients， and the total incidence ofadverse drug reactions （P＞0.05）. CAZ/AVI and prolonging therapy duration were more likely to achieve clinical benefits （odds ratios of 1.146， 7.707，P＜0.05）， while lung infection and CRRT may be independent risk factors for treatment failure （odds ratios of 0.182， 0.236， P＜0.05）. CONCLUSIONS CAZ/AVI has good efficacy and safety in the treatment of CRO infection， the appropriate extension of antibacterial treatment time can achieve a higher clinical response rate， while lung infection or CRRT may lead to treatment failure.

Analysis of risk factors of multidrug-resistant organism infection in lung transplant recipients based on restricted cubic spline model / 器官移植

Objective To summarize current status of multidrug-resistant organism (MDRO) infection in lung transplant recipients and analyze the risk factors of MDRO infection. Methods Clinical data of 321 lung transplant recipients were retrospectively analyzed. According to the incidence of postoperative MDRO infection, they were divided into the MDRO group (n=122) and non-MDRO infection group (n=199). The incidence of MDRO infection in lung transplant recipients was summarized. The risk factors of MDRO infection in lung transplant recipients were analyzed by logistic regression model. The dose-response relationship between MDRO infection and time of ventilator use was determined by restricted cubic spline model. Results Among 321 lung transplant recipients, 122 cases developed MDRO infection, with an infection rate of 38.0%. Two hundred and twenty-nine strains of pathogenic bacteria were detected in the MDRO infection group, mainly Gram-negative bacteria (92.6%), and the top three strains were carbapenem-resistant acinetobacter baumannii (46.3%), carbapenem-resistant pseudomonas aeruginosa (22.3%) and carbapenem-resistant klebsiella pneumoniae (14.8%), respectively. MDRO infection mainly consisted of lower respiratory tract infection (61.5%), followed by ventilator-associated pneumonia (26.2%). Univariate analysis showed that the risk factors of MDRO infection in lung transplant recipients were single-lung transplantation, long-time postoperative use of extracorporeal membrane oxygenation (ECMO), long operation time, long-time urinary catheterization, long-time central venous catheterization and long-time ventilator use (all P < 0.05). Multivariate logistic regression analysis indicated that single-lung transplantation and long-time ventilator use were the independent risk factors for MDRO infection in lung transplant recipients (both P < 0.05). Results of restricted cubic spline model analysis showed that the risk of infection continued to increase with the prolongation of ventilator use time within 20 d. After 20 d, prolonging the time of ventilator use failed to increase the risk of infection, showing a plateau effect. Conclusions The MDRO infection rate tends to decline in lung transplant recipients year by year. Single-lung transplantation and long-time ventilator use are the independent risk factors for MDRO infection in lung transplant recipients.