Abstract:In October 2024, World Health Organization (WHO) published a report titled Estimating the impact of vaccines in reducing antimicrobial resistance and antibiotic use, highlighting the role of vaccines in the global fight against antimicrobial resistance (AMR) through quantitative assessment for the first time, and calling for greater attention to the utilization and development of relevant vaccines. This article summarized and analyzed this report with the aim of providing insights for the development of superbug vaccines.

Abstract:Enhancing the antimicrobial stewardship level is an important issue in curbing the development and spread of microbial resistance as well as maintaining the health of the people. This study reviews the current situation of antimicrobial application both in China and abroad, sorts out the history of antimicrobial management, finds out the existing problems in the current work, and puts forward measures including attaching importance to pathogen detection, improving the infection control strategy for antimicrobial-resistant organisms, establishing a multile-vel service mechanism, forming a multidisciplinary core team, and perfecting the management system, so as to provide references for actively responding to the challenges posed by antimicrobial resistance.

Abstract:Objective To compare the clinical efficacy of high-dose tigecycline (TGC) and polymyxin B (PMB) in the treatment of pulmonary infection due to carbapenem-resistant organism (CRO). Methods Clinical data of patients with CRO pulmonary infection and received PMB or high-dose TGC combined with other antimicrobial treatment regimens in Department of Critical Care Medicine of Xiangya Hospital, Central South University from January 2019 to March 2022 were analyzed retrospectively, including basic information, pathogen detection results, antimicrobial use regimen, clinical efficacy, 30-day mortality, bacterial clearance rate, etc. Results A total of 173 patients were included in analysis, with 103 in the TGC group and 70 in the PMB group. Compared with TGC group, PMB group had a higher score of acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) (25.0 vs 20.0, P<0.001), but clinical efficacy rates were not statistically different (67.1% vs 52.4%, P=0.054). Stratified analysis revealed that when the APACHE Ⅱ score was ≥15 points, compared with TGC group (n=78), PMB group (n=66) had a higher APACHE Ⅱ score (27.0 vs 22.0, P=0.005) and a higher clinical efficacy rate (66.7% vs 47.4%, P=0.020). After adjusting confounding factors through logistic regression analysis, it was found that PMB treatment was a protective factor for clinical efficacy rate compared with TGC treatment. Conclusion For treating pulmonary infection caused by CRO in patients, PMB-based treatment regimen has a significant protective effect on the clinical efficacy rate compared with the high-dose TGC-based treatment regimen.

Abstract:Objective To explore the antimicrobial activity of the bacteriocin (tentatively named garvicin LG6) secreted by Lactococcus garvieae (L. garvieae) SHAMU-LG6 against Staphylococcus aureus (S. aureus) of different hemolytic phenotypes. Methods S. aureus isolated from clinical patients in a hospital of Anhui from 2021 to 2023 were collected. The hemolytic phenotypes of S. aureus were detected by three-point inoculation method. S. aureus of different hemolytic phenotypes were further categorized into methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) according to antimicrobial susceptibility testing results. The antagonistic activity of L. garvieae SHAMU-LG6 against S. aureus of different hemolytic phenotypes was assayed by Oxford cup me-thod. The whole-genome sequencing of L. garvieae SHAMU-LG6 was performed. Biosynthetic gene cluster of garvicin LG6 was searched by online databases antiSMASH 7.0 and BAGEL4. Through macroporous resin adsorption, ethanol gradient elution, rotary evaporation, and dried material reconstitution, antimicrobial activity of garvicin LG6 crude extract against S. aureus was detected by the inhibitory testing of Oxford cup method. Results L. garvieae SHAMU-LG6 could significantly antagonize MSSA and MRSA of different hemolytic phenotypes. Biosynthetic gene cluster of garvicin LG6 was present on the chromosomal genome of L. garvieae SHAMU-LG6. The antimicrobial activity of garvicin LG6 secreted by a single colony or 6 mL fermentation fluid of L. garvieae SHAMU-LG6 were at least equal to that of antibiotic disc of 30 μg cefoxitin. Conclusion Garvicin LG6 can efficiently kill MSSA and MRSA of different hemolytic phenotypes, and has the potential to be developed into a novel antimicrobial agent, which has great prospects for clinical application.

Abstract:Objective To explore the clinical characteristics, antimicrobial resistance, virulence and molecular epidemiology characteristics of carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKP). Methods Carbapenem-resistant Klebsiella pneumoniae (CRKP) strains isolated from clinical specimens in a tertiary first-class teaching hospital from 2018 to 2021 were collected. ST11 CR-hvKP strains were screened through the detection of antimicrobial resistance genes and virulence genes as well as multilocus sequence typing (MLST). Basic clinical information, antimicrobial resistance genes and virulence genes were analyzed. Twenty-three strains of ST11 CR-hvKP were randomly selected for virulence phenotype analysis; 45 strains of CR-hvKP were randomly selected for homology analysis by pulsed-field gel electrophoresis (PFGE). Results There were a total of 124 clinically isolated strains of ST11 CR-hvKP from 2018 to 2021, mainly from the department of neurosurgery (33.87%). The major specimen source was sputum (56.45%), the average age of infected patients were (55.2±16.4) years old, and the majority were male patients (77.42%). Antimicrobial susceptibility testing results showed these strains were resis-tant to most clinically commonly used antimicrobial agents. Virulence detection showed that virulence varied among these strains, but most of them were hypervirulence strains. PFGE analysis results showed that the strains were mainly subtype A1(63.4%). Conclusion ST11 CR-hvKP presents multidrug resistance and hypervirulence. Clonal transmission of some strains exists in this hospital, which poses great challenges for clinical anti-infection treatment as well as prevention and control. It is necessary to strengthen the prevention and control of healthcare-associated infection.

Abstract: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 sequencing results showed that 93.0% (53/57) of CRKP carried bla_KPC-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.

Abstract:Objective To explore the resistance mechanism of tigecycline insensitivity of multidrug-resistant Acinetobacter baumannii, and provide reference for clinical rational antimicrobial use as well as prevention and control of healthcare-associated infection. Methods 22 strains of tigecycline insensitive multidrug-resistant Acinetobacter baumannii (TIS-MDR-AB) and 22 strains of tigecycline sensitive multidrug-resistant Acinetobacter baumannii (TS-MDR-AB) isolated clinically from the First Affiliated Hospital of Guangzhou Medical University from April 2022 to May 2023 were collected. Efflux pump phenotype inhibition assay was performed using efflux pump inhibitor carbonyl cyanide m-chlorophenylhydrazone (CCCP). The main efflux pump genes (adeB, adeG, adeJ), as well as tigecycline-resistant gene tet (X), were screened by polymerase chain reaction (PCR) technique, and their mRNA expression levels were detected by real-time fluorescence quantitative PCR. Mutations in the efflux pump regulatory gene adeRS were analyzed by Sanger sequencing analysis. Results The detection rates of efflux pump genes adeB, adeG and adeJ were all above 95% in two MDR-AB groups, and tet (X) gene was not detected. Efflux pump inhibitor assay showed that the minimum inhibitory concentration (MIC) of TIS-MDR-AB strains decreased after adding CCCP, 3 strains showed positive efflux pump phenotype. The mRNA expression level of MDR-AB adeB in the TIS-MDR-AB group was higher than that in the TS-MDR-AB group (P<0.01), while the expression of adeG and adeJ genes was no statistically different. Multiple mutations were found in the adeR and adeS genes, the adeS of 2 strains was inserted ISAba1, and 3 strains were inserted ISAba13. Conclusion The overexpression of adeABC in the efflux pump system may play an important role in the mechanism of reduced sensitivity of MDR-AB to tigecycline, and its overexpression may be related to the insertion sequence or mutation in the efflux pump regulatory gene adeRS.

Abstract:Objective To understand the distribution characteristics and antimicrobial resistance of Serratia marcescens (S. marcescens), provide evidence for rational application of antimicrobial agents as well as prevention and control of S. marcescens infection. Methods Electronic medical record data of hospitalized patients who were detected S. marcescens at Shengjing Hospital of China Medical University from 2017 to 2023 were collected and analyzed statistically. Results From 2017 to 2023, a total of 388 strains of S. marcescens were detected, 238 strains (61.34%) were isolated from male patients and 150 strains (38.66%) from female patients; 95 strains (24.49%) were from children under 14 years old, 144 strains (37.11%) were from adults under 60 years old, and 149 strains (38.40%) were from elderly people over 60 years old, 33 strains were from newborns, accounting for 8.51% of the total strains and 34.74% of strains from children. From 2017 to 2023, the detection rate of S. marcescens remained relatively stable with small fluctuations (0.52%-0.60%), the detected specimens were mainly sputum (38.92%), with department of surgery (39.69%)being the most and department of gynecology and obstetrics being the least(1.55%). From 2017 to 2023, the resistance rate of S. marcescens to cefazolin was the highest (97.42%), fo-llowed by cefuroxime (71.13%), tetracycline (59.02%), cefamandole (57.47%), amoxicillin/clavulanic acid (44.59%), ampicillin/sulbactam (42.53%), cefoxitin (34.02%), chloramphenicol (15.21%), and furantoin (14.18%). The resistance rates of S. marcescens to quinolones from 2017 to 2023 were 0.52%-8.25%. Polymyxin-resistant and tigecycline-resistant S. marcescens emerged in 2022 and 2023, respectively. Conclusion In clinical practice, antimicrobial agents should be selected rationally for the treatment of S. marcescens infection, and S. marcescens should be focused in monitoring as well as infection prevention and management, so as to prevent and control the occurrence of S. marcescens infection.

Abstract:Objective To explore the activity and mechanism of polymyxin B combined with novel β-lactam/β-lactamase inhibitor combinations on biofilm of polymyxin B-resistant Pseudomonas aeruginosa and Klebsiella pneumo-niae. Methods The minimum inhibitory concentration (MIC), minimum biofilm inhibitory concentration (MBIC), and minimum biofilm eradication concentration (MBEC) of all antimicrobial agents were determined by micro-broth dilution method and MBEC^TM assay. The crystal violet staining method was adopted to evaluate the effect of polymyxin B combined with cefepime/avibactam, ceftazidime/avibactam, meropenem/avibactam, aztreonam/avibactam, meropenem/vaborbactam, and imipenem/relebactam at sub-MIC doses on inhibition of biofilm formation and eradication of mature biofilm. The best combination scheme for anti-biofilm activity was screened out, and anti-biofilm mechanism of this combination scheme was preliminarily explored with phenol-sulfuric acid method, bacterial motility test, and quorum sensing inhibition test. Results The MBIC and MBEC of all antimicrobial agents were higher than MIC. The combination regimen based on polymyxin B could inhibit the formation of biofilms and eradicate mature biofilm in Pseudomonas aeruginosa and Klebsiella pneumoniae. The combination of polymyxin B with cefepime/avibactam had the highest inhibition and eradication rates, ranging 67.99%-90.16% and 58.26%-63.86%, respectively. The combination of polymyxin B and cefepime/avibactam could inhibit the extracellular polysaccharides of Klebsiella pneumoniae, with inhibition rates of 34.04%-61.10%, this combination could also reduce the swimming and twitching motility diameters of bacteria. Cefepime/avibactam monotherapy on quorum sen-sing signaling molecules presented concentration dependent inhibitory effect, and when combined with polymyxin B, the inhibitory effect was consistent with that of monotherapy. Conclusion Polymyxin B and cefepime/avibactam may be potential scheme for clinical treatment for severe biofilm-associated infection caused by polymyxin B-resistant strains, and their mechanisms may be related to the inhibition of bacterial extracellular polysaccharides and motility.

Abstract:Objective To study the horizontal transfer mechanism of optrA gene-carrying linezolid-resistant Enterococcus faecalis (LREf) among clinical Enterococcus faecalis mediated by plasmids. Methods Non-repeated LREf from a tertiary first-class hospital in Kunming City from August 2022 to August 2023 were collected and identified by matrix-assisted laser desorption/ionisation-time of flight mass spectrometry (MALDI-TOF MS). Antimicrobial susceptibility testing was performed by VITEK 2 Compact, disc diffusion method and microbroth dilution method, optrA gene was detected by polymerase chain reaction (PCR), molecular biology characteristics of LREf was analyzed by whole-genome sequencing (WGS), LREf as the donor strain and clinically isolated Enterococcus faecalis as the recipient strain for conjugation test. Results A total of 17 LREf strains were collected, optrA gene was detected from plasmids of 12 LREf strains. Multiple resistance genes and virulence genes were detected. 12 LREf strains were mainly ST16 type (50.0%). Among the 24 transconjugates in the conjugation test, 8 were successfully conjugated, with a conjugation rate of 33.3%. Further analysis revealed that IS1216E insertion sequences presented at upstream and downstream of the optrA gene on the plasmid before and after conjugation of strains, and formed IS1216E-fexA-optrA-erm (A)-IS1216E-like transposon units. Conclusion The optrA gene can be horizontally transferred among clinical Enterococcus faecalis by mediating of plasmid of genes carrying both erm (A) and fexA, and the insertion sequence IS1216E plays an important role in its horizontal transfer process.

Abstract:Objective To explore and analyze the characteristics and transmission routes of carbapenem-resistant Klebsiella pneumoniae (CRKP) strains in intensive care unit (ICU). Methods From January to October 2023, 17 clinical infection isolates (clinical infection group), 5 active screening isolates (active screening group), and 7 environmental isolates (environmental group) of CRKP in the liver surgery ICU of a hospital were selected and analyzed by whole-genome sequencing. The differences in resistance genes, virulence genes, and sequence typing (ST) were compared, and transmission routes were analyzed based on the phylogenetic tree. Results 29 strains of CRKP carried 4-18 resistance genes and 52-98 virulence genes, respectively. There were no statistically significant diffe-rences in genotype distribution of resistance genes, the number of virulence genes, and gene types among three groups of CRKP (all P>0.05). ST showed that 29 CRKP strains mainly consisted of two categories: ST11 and ST15. Based on the phylogenetic tree constructed from the core genome, there were 7 highly homologous groups of CRKP, among which 4 groups had clear epidemiological associations. Conclusion CRKP in ICU carries more resistance and virulence genes, and some strains are highly homologous in ST and phylogenetic tree, which may lead to cross transmission. In the future, prevention and control measures should be strengthened to reduce the transmission of CRKP.

Abstract:Objective To investigate risk factors for the occurrence of an outbreak of surgical site infection (SSI) in the orthopedic department of a hospital. Methods Patients with SSI in the orthopedic department of a hospital in June-July 2017 were investigated, and the high-risk factors for infection were analyzed through case-control study. Specimens were taken from patients, health care workers (HCWs), environment and surgical devices for microbial detection. The homology between patients’ and environmental isolates was analyze by pulsed-field gel electrophoresis (PFGE). Results Staphylococcus aureus (S. aureus) were isolated from nasal secretion of four HCWs, including one doctor (D1) who was also isolated S. aureus from his forehead and hands. PFGE analysis found that S. aureus isolated from incision secretion of 2 patients were homologous to S. aureus isolated from the nasal cavity, forehead, and hands of doctor D1. Several targeted comprehensive infection control measures were implemented, including suspending sterile manipulation (such as surgery and dressing changes) of doctor D1; decolonization for all HCWs (including doctor D1) who carried S. aureus, requiring doctor D1 regularly trim nasal hair; strengthening the education and supervision of sterile manipulation and hand hygiene; implementing centralized isolation for SSI patients, et al. After timely implementation of the above comprehensive intervention measures, this SSI outbreak was effectively controlled in a short period of time. Conclusion Colonization of S. aureus in surgeons may lead to SSI in patients, regular active screening and decolonization of surgeons involved in specific surgeries can be considered, and if necessary, nasal colonized people with dense nasal hair are required to regularly trim their nasal hair to reduce the occurrence of SSI.

Abstract:Objective To investigate a cluster of healthcare-associated infection (HAI) of carbapenem-resistant Klebsiella pneumoniae (CRKP) in intensive care unit (ICU) of a traditional Chinese medicine hospital, and provide evidence for the prevention and control of multidrug-resistant organisms in hospitals. Methods From January to July 2023, multiple cases of CRKP infection in the ICU of a traditional Chinese medicine hospital occurred, surpassing the number in the same period of previous years. Through collection of patients’ clinical information, epidemiological investigation and environmental hygiene monitoring, the isolated CRKP strains were identified by pulsed-field gel electrophoresis (PFGE), possible causes of transmission were found out, and corresponding control measures were taken. Results During the study period, a total of 13 patients were confirmed to have developed CRKP infection, mainly respiratory tract infection, bloodstream infection, and abdominal infection. Environmental monitoring showed that only 2 out of 131 environmental object surfaces specimens and staff’s hand specimens tested positive for CRKP. PFGE identification showed that the 2 CRKP strains isolated from the sink specimens were highly homologous to the strains isolated from 2 recently admitted patients. Some strains isolated from patients were highly homologous, indicating a possibility of cross transmission. Conclusion CRKP is prone to be cross-transmission among ICU patients and contaminates the environment. Early warning and investigation should be conducted to prevent the occurrence of HAI outbreaks.

Abstract:Objective To explore the clinical characteristics as well as infection prevention and control strategies of patients with Candida auris (C. auris) infection/colonization. Methods Clinical characteristics as well as prevention and control measures of patients detected with C. auris in a general hospital from September 2023 to March 2024 were analyzed, prevention and control measures were evaluated. Results A total of 9 patients were detected C. auris, and the specimen sources were urine from 5 cases (55.56%), sputum from 3 cases (33.33%), and abdominal drainage fluid from 1 case (11.11%). There were 5 cases of community-associated infection (55.56%), 3 cases of community colonization (33.33%), and 1 case of hospital colonization (11.11%). There were 5 cases of deaths (55.56%), 3 cases of discharges (33.33%), and 1 case of transfer (11.11%). Through measures such as training, early warning, single-room isolation, personal protection, hand hygiene, environmental cleaning and disinfection and strengthening supervision on sampling process, supervising sampling detection and screening, terminal disinfection, and ensuring a qualified detection result of specimens before admitting new patients, no C. auris was detected from patient’s surrounding environment sampling, and no cross-transmission occurred in the hospital. Conclusion Paying attention to the implementation of prevention and control measures for C. auris infection can effectively control the occurrence and cross transmission of healthcare-associated infection.

Abstract:Objective To explore the impact of antimicrobial volume-based procurement (VBP) and classification management policy on the clinical use of carbapenem antibiotics. Methods Changing trend in defined daily doses (DDDs), procurement cost (Cost), defined daily dose cost (DDDc), and DDDs per 1 000 inhabitants daily (DID) of carbapenem antibiotics in all levels of medical institutions were analyzed by Mann-Kendall trend test. May 1, 2020 was taken as the intervention cut-off point of VBP policy, September 2021 was as intervention cut-off point of cla-ssification management list. The impact of VBP and classification management policy on the clinical use of carbape-nem antibiotics were studied by interrupted time series analysis. Results After implementing VBP policy, the DDDs and DID of carbapenem antibiotics increased obviously, but the long-term trend didn’t change significantly. Compared with before the implementation of the policy, the cost and DDDc of carbapenem antibiotics decreased immediately, the long-term trend of DDDc changed significantly, but the long-term trend of cost didn’t change significantly. The DDDs and Cost of carbapenem antibiotics decreased immediately after the update of classification ma-nagement list, but the long-term downward trend was not significant, and DDDc presented a long-term upward trend. Conclusion VBP policy reduces the DDDc and short-term cost of carbapenem antibiotics, but its long-term impact on DDDs, cost and DID is limited. Classification management has limited impact on the use of carbapenem antibiotics in medical institutions.

Abstract:Objective To analyze the drug resistance and genomic characteristics of clinically isolated hypermucoviscous Klebsiella pneumoniae (hmKp). Methods Klebsiella pneumoniae isolated from clinical specimens from the sentinel hospitals of National Pathogen Identification Network in Huai’an City from 2019 to 2023 were collected, strains were identified by VITEK 2 Compact, mucus phenotype was determined by string test, resistance of hmKp was determined by microbroth dilution method. Molecular typing was conducted by whole-genome sequencing technology, annotation of virulence and resistance genes carried by strains was performed. Results A total of 60 strains of hmKp were collected, mainly isolated from sputum specimens (33.33%) and blood specimens (28.33%). The average genome size of 60 strains was 5.6 Mb, with an average GC content of 57.09%. Multilocus sequence typing (MLST) showed that there were 28 ST types, with the dominant ST types being ST11 (11.67%), ST15 (11.67%), and ST412 (10.00%). Core genome MLST (cgMLST) analysis revealed that some strains were highly homologous, and no outbreak strains were found. Multidrug-resistant strains accounted for 60.00%, while imipe-nem-resistant strains accounted for 28.33%. 64 types of resistance genes were carried, 84.38% of which were located on mobile element. The carriage rates of fosfomycin-related resistance genes and extended-spectrum β-lactam antibiotic-related resistance genes were relatively high in the strains, at 100% and 98.33%, respectively. Among carbapenem-resistance gene bla_KPC-2, 21.67% was carried by ST11, ST1, and ST15 strains, among bla_NDM-5 gene, 3.33% was carried by ST76 strain. A total of 101 virulence genes were carried, most were Colibactin and type Ⅵ secretion system-related virulence genes. All strains carried capsule synthesis regulation-related genes (rcsA, rcsB), efflux pump-related genes (acrA, acrB), and enterobacterin-related genes (entABCEF, fepABCDFG, fes). Conclusion Clinically isolated hmKp in Huai’an exhibits multidrug resistance, with dominant ST types ST11, ST15, and ST412, carrying multiple horizontally transferable resistance and virulence genes, prevention and control measures should be strengthened.

Abstract:Objective To compare two methods for calculating antimicrobial use density (AUD), select the more suitable AUD for monitoring and management, and achieve rational assessment of AUD. Methods A calculation model for real-time monitoring on AUD and AUD of discharged patients was established. The AUD of 13 clinical departments and the whole hospital of a hospital from January to May 2023 calculated by two calculation methods was statistically analyzed, the dispersion was compared to evaluate their applicability, the impact of two calculation methods on departmental assessment was measured. From June 2023, the real-time monitoring AUD system began to be adopted to achieve triple monitoring on departments, doctors, and drugs. From July, assessment was initiated, changing trend of AUD calculated by two calculation methods after control in 2023 was compared. Results AUD of real-time monitoring had a smaller department monthly dispersion compared with the AUD of discharged patients, with no significant difference among the whole hospital, making the assessment more rational. After implementing management based on real-time monitoring of AUD, defined daily doses (DDDs) decreased by 4.54 in June 2023, and decreased by 2.75 DDDs in the whole year of 2023. Conclusion Real-time monitoring on AUD can better reflect the actual medication level, is more applicable, and is conducive to scientific management of AUD.

Abstract:Objective To explore the clinical characteristics and influencing factors for prognosis of patients with bloodstream infection (BSI) caused by Stenotrophomonas maltophilia (S. maltophilia). Methods Clinical data of patients with S. maltophilia BSI in Liuzhou People’s Hospital from January 2019 to December 2023 were retrospectively analyzed. Patients were divided into good prognosis group and poor prognosis group according to their prognosis. Risk factors for poor prognosis were analyzed by univariate analysis and binary logistic regression analysis. Results From 2019 to 2023, a total of 36 patients were diagnosed with S. maltophilia BSI, with an average age of (51.8±22.6) years. The most common clinical symptom was fever (91.7%), followed by respiratory symptoms (25.0%). 33 patients (91.7%) had underlying diseases, 31 patients (86.1%) had healthcare-associated infection, and 23 patients (63.9%) underwent invasive procedures before onset. Among the 36 patients with S. maltophilia BSI, 12 (33.3%) had a poor prognosis. Univariate analysis showed that underlying blood diseases, length of hospital stay ≥30 days, agranulocytosis, and elevation of C-reactive protein (CRP) were related to poor prognosis of patients with S. maltophilia BSI (all P<0.05). Binary logistic regression analysis results showed that underlying blood diseases, length of hospital stay ≥30 days, and agranulocytosis were independent risk factors for poor prognosis in patients (all P<0.05). Conclusion Patients with S. maltophilia BSI are critically ill with high mortality. Underlying blood diseases, length of hospital stay ≥30 days, and agranulocytosis are independent risk factors for poor prognosis in patients.

Abstract:Objective To investigate the impact of respiratory colonization of carbapenem-resistant Acinetobacter baumannii (CRAB) on 28-day mortality of patients with severe/critical coronavirus disease 2019 (COVID-19) in intensive care unit (ICU). Methods Clinical data were collected from severe/critical COVID-19 patients admitted to general ICU and respiratory ICU in a tertiary Chinese medicine hospital from December 9, 2022 to December 9, 2023. According to the detection results of CRAB from sputum culture during ICU stay, patients were divided into respiratory CRAB colonization group and non-CRAB colonization group. Kaplan-Meier survival curve was plotted to compare the 28-day mortality between two groups of patients after ICU admission. Relationship between respiratory CRAB colonization and 28-day mortality was explored by Cox proportional hazards model, and subgroup analysis was performed. Results A total of 88 patients with severe/critical COVID-19 were included in analysis, out of which 27 had respiratory CRAB colonization (CRAB colonization group) and 61 didn’t have respiratory CRAB colonization (non-CRAB colonization group); 37 patients (42.0%) died within 28 days after admission to the ICU. Kaplan-Meier survival curve showed that the 28-day mortality in CRAB group was higher than that in non-CRAB group (66.7% vs 31.1%, P<0.001). Cox univariate analysis showed that the 28-day mortality risk of patients in the CRAB colonization group was 2.91 folds of those in the non-CRAB colonization group (HR=2.91, 95%CI: 1.52 -5.58; P<0.05). After covariates adjusting for age, sex, underlying diseases, white blood cell count, neutrophil-to-lymphocyte ratio, hypersensitive C-reactive protein, respiratory frequency, oxygenation index, lactate dehydrogenase, urea nitrogen, creatinine, lactic acid, and D-dimer, the risk of death in the CRAB colonization group was still higher than that in the non-CRAB colonization group (HR=2.54, 95%CI: 1.15-5.58; P<0.05). Subgroup analysis showed that respiratory CRAB colonization and 28-day mortality in severe/critical COVID-19 ICU patients was affected by gender, serum albumin, creatinine, and D-dimer levels (interaction P<0.05 for all). Conclusion The short-term mortality of severe/critical COVID-19 patients in the ICU increases significantly after secondary colonization of respiratory CRAB. Effective prevention and control of colonization and infection by multidrug-resistant organisms are crucial for ensuring patient prognosis.

Abstract:Sink-associated multidrug-resistant organism (MDRO) infection is primarily caused by multidrug-resistant Gram-negative bacilli. The utilization of waterless care can reduce the incidence of such infections and colonization rate, halt outbreaks, and decrease the usage of antimicrobial agents. This paper elucidates the mechanisms of sink-associated MDRO infection, sink configurations and utilization conditions, as well as relevant intervention measures, and expounds the procedures, implementation effect, and implications of waterless care, aiming to provide reference for related research and clinical practice.