Objective To investigate the susceptibility and resistance of clinical isolates collected from hospitals in several regions of China. Methods These clinical strains were collected from 51 hospitals. Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems. Results were analyzed according to CLSI 2021 breakpoints. Results A total of 301 917 clinical isolates were collected from January to December 2021, of which gram negative organisms and gram positive cocci accounted for 71.4% and 28.6% respectively. Methicillin-resistant strains in S. aureus (MRSA), S. epidermidis and other Staphylococcus species (except S. pseudintermedius and S. schleiferi) accounted for 30.0%, 80.7% and 77.7% respectively. MR strains showed much higher resistance rates to most of other antimicrobial agents than MS strains. However, 92.4% of MRSA strains were still susceptible to trimethoprim-sulfamethoxazole, while 90.7% of MRSE strains were susceptible to rifampin. No staphylococcal strains were found resistant to vancomycin. E. faecalis strains demonstrated much lower resistance rates to most of the drugs tested than E. faecium. A few strains of both Enterococcus species were resistant to vancomycin. The prevalence of PSSP was 97.8% in the non-meningitis S. pneumoniae isolates from children and 95.1% in the non-meningitis S. pneumoniae isolates from adults. The Enterobacterales strains were still highly susceptible to carbapenems. Overall, less than 13% of these strains were resistant to carbapenems. K. pneumoniae isolates showed increasing resistance rates to imipenem and meropenem, from 3.0% and 2.9% in 2005 to 25.0% and 26.3% in 2018. However, the resistance rates of Klebsiella pneumoniae to imipenem and meropenem decreased since 2019. About 65.6% and 66.5% of Acinetobacter spp. were resistant to imipenem and meropenem, respectively. Overall, 23.0% and 18.9% of the Pseudomonas aeruginosa isolates were resistant to imipenem and meropenem, respectively. Conclusions Bacterial resistance to commonly used antibiotics is still on the rise. However, the prevalence of carbapenem-resistant K. pneumoniae and P. aeruginosa is decreasing in recent years. It is suggested that strengthening the monitoring of bacterial resistance and multidisciplinary teamwork are effective in controlling the spread of drug-resistant bacteria.

碳青霉烯类耐药革兰阴性菌（CRGNB）的广泛播散是一个全球性的公共卫生问题。CRGNB临床分离株通常呈现广泛耐药或全耐药,对其感染的抗菌治疗方案有限、死亡率高。由感染病临床诊疗、临床微生物、临床药理、医院感染控制及指南方法学等多学科专家组成的指南制定小组,根据现有科学证据制定了本临床实践指南,以解答有关CRGNB检测、抗菌治疗及感染预防控制的系列临床优先问题。本指南聚焦于碳青霉烯类耐药肠杆菌目细菌、碳青霉烯类耐药鲍曼不动杆菌和碳青霉烯类耐药铜绿假单胞菌,从当前临床实践的角度提出16个临床问题,采用人群、干预、对照及预后（population, intervention, comparator, outcomes,PICO）格式转换为研究问题,全面收集和综合分析相关研究证据。采用推荐的分级、评估、制定与评价（grading of recommendations, assessment, development and evaluation, GRADE）方法评估相应干预措施的证据体质量、效益及风险,从而制定推荐意见或建议。随机对照临床试验及系统评价获得的结果被优先用于治疗相关临床问题的推荐证据。在缺乏随机对照临床试验的情况下,观察性研究、非对照研究和专家意见被考虑作为补充证据。推荐意见分为强推荐或弱推荐（有条件推荐）。结合中国的临床实践经验,本指南同时提出实施建议,便于指南推荐意见的临床实施。本指南对耐药菌感染诊疗相关的临床医师等多学科专业人员具有参考价值。

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in healthcare facilities in major regions of China in 2023. Methods Clinical isolates collected from 73 hospitals across China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems. Results were interpreted using the 2023 Clinical & Laboratory Standards Institute (CLSI) breakpoints. Results A total of 445 199 clinical isolates were collected in 2023, of which 29.0% were gram-positive and 71.0% were gram-negative. The prevalence of methicillin-resistant strains in Staphylococcus aureus, Staphylococcus epidermidis and other coagulase-negative Staphylococcus species (excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi) (MRSA, MRSE and MRCNS) was 29.6%, 81.9% and 78.5%, respectively. Methicillin-resistant strains showed significantly higher resistance rates to most antimicrobial agents than methicillin-susceptible strains (MSSA, MSSE and MSCNS). Overall, 92.9% of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 91.4% of MRSE strains were susceptible to rifampicin. No vancomycin-resistant strains were found. Enterococcus faecalis had significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium. A few vancomycin-resistant strains were identified in both E. faecalis and E. faecium. The prevalence of penicillin-susceptible Streptococcus pneumoniae was 93.1% in the isolates from children and and 95.9% in the isolates from adults. The resistance rate to carbapenems was lower than 15.0% for most Enterobacterales species except for Klebsiella, 22.5% and 23.6% of which were resistant to imipenem and meropenem, respectively . Most Enterobacterales isolates were highly susceptible to tigecycline, colistin and polymyxin B, with resistance rates ranging from 0.6% to 10.0%. The resistance rate to imipenem and meropenem was 21.9% and 17.4% for Pseudomonas aeruginosa, respectively, and 67.5% and 68.1% for Acinetobacter baumannii, respectively. Conclusions Increasing resistance to the commonly used antimicrobial agents is still observed in clinical bacterial isolates. However, the prevalence of important crabapenem-resistant organisms such as crabapenem-resistant K. pneumoniae, P. aeruginosa, and A. baumannii showed a slightly decreasing trend. This finding suggests that strengthening bacterial resistance surveillance and multidisciplinary linkage are important for preventing the occurrence and development of bacterial resistance.

Objective To evaluate the safety and efficacy of amphotericin B colloidal dispersion (ABCD) in the salvage treatment of invasive fungal disease (IFD). Methods A total of 106 patients who received ABCD salvage therapy from April to August 2021 after failure of previous antifungal therapy were reviewed and analyzed retrospectively. The demographic and clinical data and ABCD-related adverse reactions were summarized with descriptive statistics. Results Transfusion reactions were the most common ABCD-related adverse events in the 106 patients, including chills (60.4%), fever (54.7%) and fear of cold (11.3%). Most of the adverse reactions were grade 1 or 2. The efficacy rate of ABCD treatment was 85.8% (91/106, 95% CI: 77.7%-91.9%) in all of the patients, and 92.6% (25/27, 95% CI: 75.7%-99.1%) in the patients with proven/probable IFD, including mucormycosis (n=9), invasive pulmonary aspergillosis (n=5), cryptococcal meningitis (n=5), talaromycosis (n=3), pulmonary moniliasis (n=2), and one of three patients with candidemia. ABCD salvage treatment succeeded in all of the seven patients with proven/probable IFD who received prior polyene antifungal therapies. All patients with proven/probable IFD were alive within 6 weeks after ABCD treatment. Conclusions ABCD is safe and well-tolerated in the treatment of IFD with low renal toxicity. ABCD salvage treatment is also effective in patients who are intolerant of or failed to prior antifungal therapy.

目的对诺卡菌培养阳性病例的临床特点进行分析,提高对该菌感染的认识。方法回顾性分析宁夏医科大学总医院2012年5月-2014年12月住院患者标本培养为诺卡菌阳性的11例患者的临床资料。结果11例诺卡菌培养阳性病中2例考虑污染所致,9例为不同部位感染的患者,其中6例为肺部感染,2例为皮肤软组织感染,1例为透析相关性腹膜炎;9例均合并基础疾病,其中4例因基础病使用糖皮质激素或免疫抑制剂。结论诺卡菌可引起全身各部位感染,以肺为常见。有基础疾病者易发生诺卡菌感染,尤其使用糖皮质激素及免疫抑制剂患者。

Objective To explore the effect of bedaquiline on QT interval when comnined with clofazimine and fluoroquinolones in patients with multidrug-resistant tuberculosis (MDR-TB) for safe drug use and monitoring of drug adverse reactions. Methods Ninety-one eligible patients were enrolled in Chengdu Public Health Clinical Medical Center from March 2018 to March 2020 according to the inclusion and exclusion criteria. All the patients received bedaquiline-containing treatment regimen. The electrocardiograph (ECG) was recorded at baseline, and at end of 2, 4, 8, 12, 16, 20, 24, and 36 weeks after initiation of treatment, and compared between the patients receiving clofazimine co-treatment (n=55) and those not receiving clofazimine (n=36). Results Bedaquiline combined with clofazimine resulted in significantly higher incidence (54.5%, 30/55) of QTcF prolongation ≥ 60 ms from baseline than the regimen not containing clofazimine (33.3%, 12/36) (P < 0.05). The incidence of QT prolongation was 45.9% when bedaquiline combined with one drug causing QT prolongation, which was not significantly different from the incidence of 52.4% (P > 0.05) when bedaquiline combined with two drugs causing QT prolongation. Conclusions Bedaquiline combined with clofazimine led to significantly higher incidence of QTcF prolongation ≥ 60 ms from baseline than the regimen not containing clofazimine in patients with MDR-TB. The patients should be monitored closely for cardiac symptoms and ECG abnormalities during combination treatment with bedaquiline and clofazimine.

Objective To investigate the clinical manifestations, diagnosis and treatment of catheter-related bloodstream infection caused by Tsukamurella species, and improve clinicians' awareness of this disease. Methods Data were retrospectively collected from a patient who was diagnosed with catheter-related bloodstream infection caused by Tsukamurella species. The databases of PubMed, CNKI, Wanfang and VIP were searched, using the term “Tsukamurella”, to identify the reported cases of catheter-related bloodstream infection caused by Tsukamurella species. The relevant data were extracted for further analysis. Results Our case was a 37-year-old male with underlying diseases including short bowel syndrome, hypersplenism, and intra-abdominal desmoid tumor, who had a long-term indwelling peripherally inserted central catheter. He presented with fever, and was diagnosed with catheter-related bloodstream infection caused by Tsukamurella species based on cultures of peripheral blood sample and catheter tip. He eventually recovered after antimicrobial treatment with cefoperazone-sulbactam followed by imipenem-cilastatin. We identified 56 cases in the literature search, of which most patients were immunocompromised. Chemotaxonomic and/or molecular methods were utilized for pathogen identification in most cases. Intravascular catheters were removed for treatment in most of the patients. Overall, one patient died, 54 patients survived, and the outcome of one patient was unknown. It was unclear whether the only death was attributable to Tsukamurella species infection. Conclusions Tsukamurella species are opportunistic pathogens, which are rarely seen in clinical practice. The identification of these bacteria relies on mass spectrometry and gene sequencing. In addition to appropriate antibiotic treatment, removal of intravascular catheters is essential to infection control.

Objective To investigate the clinical characteristics and risk factors for death of candidemia for better prevention and reasonable diagnosis and treatment of candidiasis. Methods The clinical and microbiological data of patients diagnosed with candidemia in a hospital from January 2015 to December 2019 were retrospectively analyzed. The patients were assigned to survivor group and death group according to the outcome of the patients. Univariate analysis and binary logistic regression analysis were conducted to identify the risk factors for death. Results A total of 97 patients were diagnosed with candidemia in the 5-year period. Overall, 99 strains of Candida were isolated from blood, of which Candida albicans, Candida parapsilosis, Candida glabrata, and Candida tropicalis accounted for 32.3%, 25.3%, 22.2% and 20.2%, respectively. The candidemia cases were mainly found in the department of gastroenterology (26.3%), cardiovascular surgery (23.2%), and burn and skin surgery (17.2%). The 4 Candida species showed significantly different susceptibility rates to triazole drugs (P < 0.05). Non-albicans Candida strains demonstrated higher resistance rates than C. albicans. Thirty (30.9%) of the 97 patients died. Univariate analysis showed that ICU admission, different departments, indwelling urinary catheter, chest drainage tube, and cardiovascular implant, suffered from hypertension, (1,3)-β-D-glucan > 100 ng/L were associated with mortality (P < 0.05). Binary logistic analysis indicated that ICU admission (OR=4.942, 95% CI: 1.574-15.515, P = 0.006) and indwelling pleural drainage tube (OR=5.678, 95% CI: 1.427-22.598, P = 0.014) were independent risk factors for death in patients with candidemia. Conclusions Non-albicans Candida species are the main pathogens of candidemia. ICU admission and indwelling chest drainage tube are independent risk factors for the death of patients with candidemia.

Objective To retrospectively analyze the clinical features and risk factors for death of patients with bloodstream infection (BSI) caused by Klebsiella pneumonia in adults for improving early prevention and effective treatment of K. pneumoniae BSI. Methods The medical records were collected from 114 adult patients with K. pneumoniae BSI and 335 patients with non-BSI infection caused by K. pneumoniae who were treated in Fujian Provincial Hospital from June 1, 2017 to May 31, 2019. The clinical characteristics, antimicrobial treatment, and outcomes of K. pneumoniae BSI were analyzed. SPSS 26.0 software was used to perform multivariate binary logistic regression analysis to identify the risk factors for the occurence and mortality of K. pneumoniae BSI. Results The K. pneumoniae BSI mainly occurred in intensive care unit (28.95%, 33/114), departments of hepatobiliary surgery (14.91%, 17/114), and gastroenterology (14.04%, 16/114). Malignant tumor, liver abscess, and deep venous catheterization were independent risk factors for the occurrence of K. pneumoniae BSI. K. pneumoniae BSI was associated with a significantly higher 28-day mortality rate compared with K. pneumoniae non-BSI infection (25.44% vs 14.93%, P = 0.011). The patients with K. pneumoniae BSI were also more likely to develop septic shock and complicated with multiple organ dysfunction syndrome (MODS) (P < 0.001). The prevalence of carbapenem-resistant K. pneumoniae (CRKP) was 20.18% (23/114) in adult patients with K. pneumoniae BSI. CRKP BSI was associated with significantly higher mortality rate than carbapenem-susceptible K. pneumoniae (CSKP) BSI (69.57% vs 14.29%). Presence of ≥ 2 sites of infection, CRKP infection, and APACHE II score ≥ 10 were independent risk factors for death in patients with K. pneumoniae BSI. Conclusions Patients with K. pneumoniae BSI have a high mortality rate and are prone to MODS and septic shock. Clinicians should be aware of the risk of K. pneumoniae BSI in patients with malignant tumor, liver abscess, and deep venous catheterization. Multiple sites of infection, CRKP infection, and critical condition will increase the risk of death in patients with K. pneumoniae BSI.

Objective Meta-analysis was used to investigate the diagnostic value of MxA protein for respiratory virus infection. Methods EMbase, PubMed, the Cochrane Library, China Biology Medicine (CBM), China National Knowledge Infrastructure (CNKI), and Wanfang databases were searched from the inception of these databases up to January 2022 to retrieve relevant studies on MxA protein. According to the inclusion and exclusion criteria, two researchers selected the eligible references for quality evaluation based on QUADAS-2 standard. Revman 5.3 software was used to plot the risk of bias. Stata 15.0 software was used to perform data analysis. Results A total of 14 studies were included, for which the overall risk of bias was low. For diagnosis of respiratory virus infection, MxA alone showed sensitivity Q = 15.71, P = 0.02, I ² = 61.80%, specificity Q = 11.07, P = 0.09, I ² = 45.81%. Meta-analysis indicated that the pooled sensitivity was 0.91 (95% CI: 0.86, 0.94). Pooled specificity was 0.89 (95% CI: 0.83,0.93). Pooled positive likelihood ratio (PLR) was 8.20 (95% CI: 5.20,12.80). Pooled negative likelihood ratio (NLR) was 0.10 (95% CI: 0.07, 0.16). Pooled diagnostic odds ratio (DOR) was 79.00 (95% CI: 45.00, 141.00). The area under the summary receiver operating characteristic (SROC) curve was 0.96 (95% CI: 0.93, 0.97). The rapid diagnostic test FebriDx showed sensitivity Q = 75.87, P < 0.05, I ² = 92.09%, and specificity Q = 17.79, P < 0.05, I ² = 66.27%. Meta-analysis demonstrated that the pooled sensitivity was 0.91 (95% CI: 0.80, 0.97). Pooled specificity was 0.86 (95% CI: 0.80, 0. 91). Pooled PLR was 6.60 (95% CI: 4.40, 10.00). Pooled NLR was 0.10 (95% CI: 0.04, 0.25). Pooled DOR was 65.00 (95% CI: 19.00, 222.00). The area under the SROC curve was 0.92 (95% CI: 0.89, 0.94). Deeks’ funnel plot did not show significant difference in publication bias among the studies. Conclusions MxA protein has certain diagnostic value for respiratory virus infection.

Objective:To report one case of adverse reactions in central nervous system during ertapenem treatment and to remind clinicians of such toxicity when prescribing ertapenem.Methods:We described an 87 year-old woman with complicated urinary tract infection who received ertapenem treatment (1 g,qd).On the third day after treatment,the patient began to talk nonsense and have visual hallucination.She developed tonic-clonic seizures on day 5,associated with urinary incontinence.Her conscious status improved 2 days after discontinuation of ertapenem.We also reviewed another 19 cases of ertapenem-induced neurological adverse reactions.Results:The related CNS symptoms included various types of mental abnormalities,including hallucination,delirium,delusion,disorientation,dyscalculia,tremor,seizures,and altered mental status,which were not specific.In most of the reported cases,CNS symptoms occurred about 3-7 days after initiation of ertapenem treatment,and alleviated 2 days after withdrawal of the antibiotic.However,in patients with end-stage kidney disease,the symptoms could last up to two weeks.Conclusions:The risk factors for ertapenem-induced neurological adverse reactions include high dosage,co-administration with other antibiotics causing CNS symptoms,impaired renal function,advanced age,and underlying nervous system abnormalities.Advanced age,renal dysfunction,and factual overdosage of ertapenem were the risk factors in this case.

Objective To investigate the susceptibility and resistance pattern of clinical isolates in hospitals across China. Methods These clinical strains were collected from 52 hospitals. Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems. Results were analyzed according to CLSI 2020 breakpoints. Results A total of 251 135 clinical isolates were collected from January to December 2020, of which gram negative organisms and gram positive cocci accounted for 71.9% and 28.1%, respectively. Methicillin-resistant strains in S. aureus (MRSA), S epidermidis and other Staphylococcus spp. (except S. pseudintermedius and S. schleiferi) accounted for 31.0%, 81.7%, and 77.5%, respectively. The resistance rates of MR strains to most of other antimicrobial agents were much higher than those of MS strains. However, 93.6% of MRSA strains were still susceptible to trimethoprim-sulfamethoxazole, while 89.9% of MRCNS strains were susceptible to rifampin. No staphylococcal strains were found resistant to vancomycin. E. faecalis strains showed much lower resistance rates to most of the drugs tested than E. faecium. A few strains of both species were resistant to vancomycin. Among the S. pneumoniae strains isolated from children and adults, the prevalence of PSSP (96.7% and 95.5%, respectively) strains were higher than those isolated in 2019. The prevalence of PISP and PRSP were lower than those isolated in 2019. The strains of Enterobacteriaceae were still highly susceptible to carbapenems, Overall, less than 12% of these strains (except Klebsiella) were resistant to carbapenems. The percentage of K. pneumoniae strains resistant to imipenem and meropenem increased from 3.0% to 25.0% and from 2.9% to 26.3%, respectively from 2005 to 2018. However, the prevalence of imipenem- and meropenem-resistant Klebsiella strains decreased in 2019 and 2020. About 68.1% and 69.0% of Acinetobacter spp. strains were resistant to imipenem and meropenem, respectively. The resistance rates of Pseudomonas aeruginosa to imipenem and meropenem were 23.2% and 19.3%, respectively. Conclusions The prevalence of carbapenem-resistant K. pneumoniae and P. aeruginosa decreased even though bacterial resistance to commonly used antibiotics is still on the rise. It is necessary to strengthen the surveillance of bacterial resistance and the measures for control of infectious diseases.

Objective To investigate the incidence of voriconazole-induced liver injury and the possible risk factors in the context of therapeutic drug monitoring (TDM). Methods The patients receiving voriconazole treatment and therapeutic drug monitoring and with normal initial liver function were enrolled. The patients were assigned to liver injury group or no liver injury group according to the liver function tests during voriconazole treatment. Univariate analysis and binary logistic regression were used to analyze the risk factors of liver injury. Receiver operating characteristic (ROC) curve was used to analyze the specificity, sensitivity and the best cut-off value of the risk factors in predicting the occurrence of liver injury. Results The incidence of voriconazole-induced liver injury was 28.4% in the 116 enrolled patients. Univariate and multivariate analyses showed that trough concentration and C-reactive protein (CRP) were the risk factors of voriconazole-induced liver injury. The risk of liver injury increased significantly when trough concentration > 4.80 mg/L and/or CRP > 127.86 mg/L. Conclusions The patients with high CRP level should be followed up by TDM during voriconazole treatment in order to reduce the risk of liver injury.

Objective To investigate the distribution profile of trough plasma concentration (C_min) of linezolid in patients with hepatic impairment and the factors affecting concentration variation, and to evaluate treatment efficacy and linezolid-induced thrombocytopenia. Methods Hepatic impairment patients who received standard dose of linezolid (600 mg, q12 h) were stratified according to baseline hepatic function as defined by Child-Pugh-Turcotte score criteria: mild hepatic impairment (Child-Pugh-Turcotte Class A), moderate hepatic impairment (Child-Pugh-Turcotte Class B) and severe hepatic impairment (Child-Pugh-Turcotte Class C). Linezolid C_min was measured by high-performance liquid chromatography. Data pertaining to linezolid were collected. Multivariate linear regression models were used to investigate the effect of variables on linezolid C_min. Bacterial eradication rate and incidence of linezolid-induced thrombocytopenia were analyzed in terms of hepatic impairment. Results Plasma samples were collected from 30 patients. Severe hepatic impairment patients showed significantly higher linezolid C_min than the patients with mild or moderate hepatic impairment [(19.3 ± 6.5) mg/L vs (7.5 ± 3.2) mg/L, P < 0.05; (19.3 ± 6.5) mg/L vs (11.6 ± 3.2) mg/L, P < 0.05]. Supratherapeutic linezolid Cmin was observed in 11.8%, 42.1%, and 66.7% of the patients with mild, moderate, or severe hepatic impairment, respectively. Age(≥65 years), Charlson comorbidity score(≥4 points), and severe hepatic impairment had a significant effect on linezolid C_min (P < 0.05). Bacterial eradication rate and the incidence of linezolid-induced thrombocytopenia was 70.0% and 30.0% respectively in patients with hepatic impairment. Conclusions Standard dosing regimen of linezolid still achieves high plasma concentration in patients with hepatic impairment. Plasma concentrations of linezolid should be closely monitored in patients with hepatic impairment to ensure the safety and efficacy of linezolid therapy.

Objective To evaluate the efficacy and safety of eravacycline in the treatment of complicated intra-abdominal infection (cIAI) in Chinese adult patients. Methods In this multicenter, randomized, double-blind phase III study, cIAI patients were randomly assigned to receive either eravacycline (1.0 mg/kg, q12h) or ertapenem (1 g, q24h) by intravenous infusion for 5 to 14 days. The primary and secondary efficacy endpoints included the clinical efficacy and microbiological efficacy in different populations, including modified intention-to-treat (MITT) population, clinically evaluable (CE) population, and microbiologically evaluable (ME) population, at different time points after treatment. Clinical cure rates at specific visits were summarized and compared between treatment groups in different populations. The microbial eradication rate was calculated for the patients with baseline pathogens. The incidence of adverse events (AE) and drug-related treatment emergent adverse event (TEAE) was analyzed by treatment group. Results A total of 144 patients with cIAI who received at least one dose of the study drug were included in the MITT population. The clinical cure rate was 77.8% (56/72) in eravacycline-treated patients and 90.3% (65/72) in ertapenem-treated patients at 25-31 days after the first dose (TOC visit). When the patients who received insufficient treatment (< 72 hours) were excluded, the clinical cure rate was 83.6% (56/67) in eravacycline group and 90.3% (65/72) in ertapenem. For CE and ME patients, the clinical cure rate at TOC visit was 91.1% (51/56) and 83.3% (25/30) in eravacycline group, 95.3% (61/64) and 90.9% (30/33) in ertapenem group. Eravacycline treatment achieved microbiological eradication rate of 91.3% (21/23) against Escherichia coli at TOC visit in micro-MITT population while ertapenem treatment resulted in a microbiological eradication rate of 96.2% (25/26). The microbiological efficacy of eravacycline and ertapenem against Klebsiella pneumoniae was 4/5 and 3/3, respectively. The incidence of TEAE was similar in eravacycline and ertapenem groups (75.0% vs.70.8%), most of which were mild or moderate. The AEs associated with eravacycline were mainly infusion site phlebitis (9.7%, 7/72) and infusion site pain (8.3%, 6/72). Conclusions Similar to ertapenem, eravacycline has good clinical and microbiological efficacy in treating cIAI. It is also safe and well-tolerated in the patients.

Objective This study aims to analyze the clinical characteristics, antimicrobial susceptibility, and treatments of Nocardia infections in southwest of China. Methods We conducted a retrospective survey of 33 patients clinically diagnosed with nocardiosis at West China Hospital of Sichuan University from 2010 to 2020. Results The patients included 12 females and 21 males. At least one underlying disease was reported in 28 (84.8%) patients. Immunosuppressive drugs or steroids treatment were used in 13 (39.4%) cases. The common underlying disease included chronic pulmonary disease in 9 cases (27.3%), cardiovascular disease in 8 cases (24.2%), autoimmune disease and renal disease in 7 cases each (21.2%), diabetes mellitus in 6 cases (18.2%) and liver disease in 4 cases (12.1%). The clinical type of nocardiosis included cutaneous (24.2%, 8/33), pulmonary (36.4%, 12/33), neurological (9.1%, 3/33), and disseminated nocardiosis (30.3%, 10/33). All of the Nocardia isolates (100%) were susceptible to amikacin, linezolid and tetracyclines, followed by 90.9% to trimethoprim-sulfamethoxazole (TMP-SMX), 75.0% to gentamycin, 73.7% to third or fourth generation cephalosporins, 70.0% to carbapenems, 46.7% to fluoroquinolones, and 14.3% to penicillins. Twenty-six (78.8%) patients received TMP-SMZ either as monotherapy, or in combination with carbapenems, linezolid, amikacin, or third generation cephalosporins. Twenty-seven (81.8%) patients were clinically improved after antimicrobial treatment. Treatment failed in 6 cases (18.2%). The patients were transferred to local hospital or left hospital voluntarily after treatment failure.The patients with central nervous system (CNS) nocardiosis showed evidently worse outcome than those without CNS involvement (P = 0.005).Conclusions Nocardia infection should be considered particularly in immunocompromised patients. TMP-SMX alone or in combination is still the cornerstone for treatment of nocardiosis. Nocardiosis involving CNS usually predicts worse prognosis.

Objective To analyze the clinical and etiological characteristics of anaerobic infections in open wounds of orthopedic patients and to provide evidence for the diagnosis and appropriate treatment. Methods A retrospective analysis was conducted with the clinical characteristics, etiological results and antimicrobial susceptibility of 85 cases of anaerobic infection in open wounds. The patients were treated in Beijing Jishuitan Hospital from Janaury 2015 to December 2019. Results Most patients were middle-aged males. The infections were largely polymicrobial caused by both aerobic and anaerobic bacteria, accounting for 75.2% of the cases. A total of 112 strains of anaerobic bacteria were isolated from open wound specimens. The most common anaerobic pathogen was Clostridia (24.1%), followed by Prevotella (16.9%), Bacteroides (12.5%) and Peptostreptococcus (12.5%). In vitro antimicrobial susceptibility testing showed that all of the four genera of anaerobic isolates were 100% susceptible to piperacillin-tazobactam and meropenem. Conclusions Anaerobes are the major pathogens of the open wound infections in orthopedic patients. It is necessary to perform anaerobic cultures in patients with open wound infections for appropriate patient care to avoid treatment failure.

Objective To understand the molecular epidemiology and virulence characteristics of carbapenem-resistant Klebsiella pneumoniae (CRKP) in the General Hospital of Ningxia Medical University. Methods A total of 103 CRKP strains isolated from January 2015 to December 2019 were collected. Modified carbapenem inactivation method (mCIM) combined with EDTA-modified carbapenem inactivation method (eCIM) were used to detect the carbapenemase-producing phenotype. PCR technique was used to detect carbapenemase-resistant genes, capsule serotype, and virulence genes. The homology of carbapenem-resistant hypervirulent K. pneumoniae (CR-hvKP) was analyzed by multi-locus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Results The 103 CRKP strains showed variable levels of resistance to commonly used antibiotics. Phenotyping based on mCIM and eCIM tests showed that 94 CRKP strains were carbapenemase producers, of which 67.0% produced metallo-beta-lactamase and 33.0% produced serine carbapenase. The prevalence of resistant genes was 50.5% (52/103) for bla_NDM, 33.0% (34/103) for bla_KPC, 22.3% (23/103) for bla_OXA-48, and 10.7% (11/103) for bla_IMP. MLST identified 18 ST types among the CRKP strains, mainly including ST11 (36/102, 35.3%) and ST76 (23/102, 22.5%) types. Ten CRKP strains were identified as CR-hvKP, all of which harbored fimbrial adhesion related gene fimH and siderophore enterobactin gene (entB). Only 4 of the 10 CR-hvKP strains were capsular serotype K1. PFGE-based homology analysis showed that majority of the 10 CR-hvKP strains were clsoely related and belonged to cluster D. No outbreak was found in the same ward in the same time period. Conclusions The CRKP strains in this hospital mainly produce NDM-5 carbapenemase, and ST11 is the dominant prevalent strain. About 9.7% of the CRKP strains were hypervirulent strains, which should be addressed carefully in clinical settings to prevent a potential outbreak.

多黏菌素类抗生素是目前临床用于治疗难治性革兰阴性菌感染的重要药物,在国内临床应用也呈增多趋势,但对该类药物的认识尚有不足。日前美国临床药学院(ACCP)、欧洲临床微生物和感染病学会(ESCMID)、美国感染病学会(IDSA)、国际抗感染药学会(ISAP)、重症医学会(SCCM)和感染病药师学会(SIDP)等6家国际权威学会联合发布多黏菌素类合理应用共识指南[Pharmacotherapy,2019,39(1):10-39.DOI:10.1002/phar.2209],其中基于近年来新的循证依据,对品种和剂型的选择、给药剂量及其调整、药动学/药效学治疗靶值等作了推荐。现将其中要点作成编译,以供读者参考。

Objective To know the changing distribution and antimicrobial resistance profiles of Acinetobacter spp. isolated from 51 hospitals across China from 2015 to 2021. Methods According to the CHINET antimicrobial resistance surveillance program, antimicrobial susceptibility testing for isolates was conducted by Kirby-Bauer method and automatic microbiological analysis systems. The susceptibilities of the isolates to antimicrobial agents tested were interpreted according to CLSI 2021 breakpoints. The data were analyzed by WHONET 5.6 software. Results During the period from 2015 to 2021, a total of 143 393 clinical isolates of Acinetobacter were collected, among which Acinetobacter baumannii was the most common species, accounting for 89.6% of all Acinetobacter strains. Overall, 73.0% of the Acinetobacter strains were from respiratory tract. The majority of the Acinetobacter strains were from inpatients (94.0%), of which isolates from ICUs accounted for 35.5%. Acinetobacter strains showed high resistance rates to antimicrobial agents such as β-lactams, aminoglycosides and fluoroquinolones except for minocycline, tigecycline and polymyxin B. The antimicrobial resistance pattern of Acinetobacter strains varied with different levels of hospitals and different departments. During the period from 2015 to 2021, the resistance rate of A. baumannii to cefoperazone-sulbactam and piperacillin-tazobactam had increased, while the resistance rate to minocycline and tigecycline showed a downward trend. The prevalence of carbapenem-resistant A. baumannii was high, reaching 75.2% in tertiary hospitals. Conclusions Acinetobacter spp. is an important pathogen of nosocomial infections, which showed high resistance rates to commonly used antimicrobial agents in clinical practice. Polymyxin B, tigecycline and minocycline are appropriate for treatment of multidrug-resistant Acinetobacter infections.

Objective To investigate the etiology and risk factors for mortality of bloodstream infection in diabetic patients for improving diagnosis and treatment and so the outcome of patients. Methods The clinical and laboratory data of bloodstream infections in the diabetic patients admitted to the Third People's Hospital of Mianyang City from 2017 to 2021 were retrospectively reviewed and analyzed. The etiological pathogens and susceptibility testing results were analyzed with WHONET 5.6 software. The patients were divided into survivor group and death group based on 30-day outcome. The risk factors for all-cause mortality were analyzed. Results A total of 334 diabetic patients with bloodstream infection were included in this study. Overall, 347 nonduplicate pathogenic bacteria were isolated. The top bacterial species was Escherichia coli (143 strains, 41.2%), Klebsiella pneumoniae (83 strains, 23.9%), and Staphylococcus aureus (22 strains, 6.3%). The most common pathogenic bacteria of urinary tract infections were E. coli and K. pneumoniae, while the most common pathogenic bacteria of respiratory tract infections were K. pneumoniae, E. coli, and S. aureus. More than 90% of liver abscess-derived bloodstream infections were caused by K. pneumoniae. The pathogens of bloodstream infections varied with clinical setting. Enterobacterales such as E. coli and K. pneumoniae were more frequently isolated in community-acquired infections, while P. aeruginosa, A. baumannii, and Candida were more common in nosocomial bloodstream infections. The resistance rates of E. coli to ampicillin and piperacillin were all higher than 50%, the resistance rates to piperacillin-tazobactam, imipenem, minocycline were all lower than 10%. The E. coli isolated from hospital-acquired infections showed higher resistance rates to cephalosporins, fluoroquinolones, beta-lactam/beta-lactamase inhibitor combinations and other antibiotics compared to the isolates from community-acquired infections. The resistance rates of K. pneumoniae to commonly used antibiotics were lower than 30%. The K. pneumoniae isolated from hospital-acquired infections showed higher resistance rates to cephalosporins, carbapenems, aminoglycosides, fluoroquinolones and other antibiotics compared to the isolates from community-acquired infections. Ineffective empirical antimicrobial treatment, not use insulin to control blood glucose level, occurrence of acute complications, and higher Pitt bacteremia score were risk factors for all-cause mortality in diabetic patients with bloodstream infection. The corresponding odds ratio (OR) was 8.261, 2.719, 5.263, and 1.918, respectively. Conclusions E. coli, K. pneumoniae, and S. aureus were the most common pathogens of bloodstream infection in diabetic patients. The distribution of pathogenic bacteria was related to body site and clinical setting of infection. The E. coli and K. pneumoniae isolated from hospital-acquired bloodstream infections are more resistant to commonly used antibiotics. Ineffective empirical antimicrobial treatment at early stage, not use insulin to control blood glucose level, acute complications, and higher Pitt bacteremia score were risk factors for all-cause mortality of the diabetic patients with bloodstream infection.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022. Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems. Results were interpreted using the 2022 Clinical & Laboratory Standards Institute (CLSI) breakpoints. Results A total of 318 013 clinical isolates were collected from January 1, 2022 to December 31, 2022, of which 29.5% were gram-positive and 70.5% were gram-negative. The prevalence of methicillin-resistant strains in Staphylococcus aureus, Staphylococcus epidermidis and other coagulase-negative Staphylococcus species (excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi) was 28.3%, 76.7% and 77.9%, respectively. Overall, 94.0% of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8% of MRSE strains were susceptible to rifampicin. No vancomycin-resistant strains were found. Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium. A few vancomycin-resistant strains were identified in both E. faecalis and E. faecium. The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2% in the isolates from children and 95.7% in the isolates from adults. The resistance rate to carbapenems was lower than 13.1% in most Enterobacterales species except for Klebsiella, 21.7%-23.1% of which were resistant to carbapenems. Most Enterobacterales isolates were highly susceptible to tigecycline, colistin and polymyxin B, with resistance rates ranging from 0.1% to 13.3%. The prevalence of meropenem-resistant strains decreased from 23.5% in 2019 to 18.0% in 2022 in Pseudomonas aeruginosa, and decreased from 79.0% in 2019 to 72.5% in 2022 in Acinetobacter baumannii. Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals. However, the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K. pneumoniae, P. aeruginosa, and A. baumannii showed a downward trend in recent years. This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

Objective To investigate the resistance profile of clinical Streptococcus isolates collected from hospitals in several major regions of China during the period from 2015 to 2021. Methods These clinical strains were collected from 51 hospitals. Antimicrobial susceptibility testing was carried out according to a unified protocol of CHINET using Kirby-Bauer method, E-test or automated commercial systems. Results were analyzed according to CLSI M100 2022 breakpoints. Results A total of 89 684 Streptococcus strains were collected from 2015 to 2021, including 35 254 strains (39.3%) of Streptococcus pneumoniae, 42 563 strains (47.6%) of β-hemolytic Streptococcus, and 11 767 strains (13.1%) of Streptococcus viridans. Group A, B, and unclassified Streptococcus accounted for 39.8%, 52.8% and 7.4%, respectively, among the 42 563 strains of β-hemolytic Streptococcus. The prevalence of penicillin-susceptible S. pneumoniae (PSSP), penicillin-intermediate S. pneumoniae (PISP), and penicillin-resistant S. pneumoniae (PRSP) was 86.2%-97.7%, 1.7%-6.5%, and 0.6%-7.3%, respectively, among the 25 552 S. pneumoniae strains isolated from non-cerebrospinal fluid (CSF) specimens in pediatric patients. The prevalence of PSSP, PISP, and PRSP was 92.0%-95.1%, 3.8%-5.3%, and 1.4%-2.7%, respectively, in the 7 997 strains of S. pneumoniae isolated from non-CSF specimens in adult patients. The prevalence of PRSP was 81.2% in the strains isolated from CSF specimens. Regardless of whether S. pneumoniae strains were isolated from CSF or non-CSF specimens, the strains isolated from both pediatric and adult patients were highly resistant to erythromycin and clindamycin, higher than 90% of the strains resistant in nearly all hospitals. β-hemolytic Streptococcus was sensitive to penicillin and ceftriaxone, and no resistant strains were found. The resistance rate of α-hemolytic Streptococcus to penicillin was 5.7% to 8.5%. About 46.3% to 55.0% of group B β-hemolytic Streptococcus isolates were resistant to levofloxacin, while other Streptococcus strains were still highly sensitive to levofloxacin. No strains resistant to linezolid or vancomycin were found in Streptococcus isolates. Conclusions Penicillin remains the first choice for non-central nervous system infections caused by Streptococcus. Streptococcus isolates are still highly resistant to erythromycin and clindamycin.

Objective To investigate the risk factors and outcome of cytomegalovirus (CMV) and Pneumocystis pneumonia (PCP) coinfection in the patients with acquired immunodeficiency syndrome (AIDS). Methods A total of 337 AIDS patients with PCP treated in Chongqing Public Health Medical Center from January 2020 to December 2020 were retrospectively analyzed. The patients were assigned to CMV group or non-CMV group based on CMV-DNA test result. The demographic data, clinical symptoms, laboratory tests, opportunistic infections, and outcomes of patients were compared between groups. The risk factors for CMV-PCP coinfection were investigated by logistic regression analysis. Results CMV-PCP coinfection was identified in 42.7% (144/337) of the patients. Univariate analysis showed that pH value, arterial oxygen partial pressure (PaO₂), C-reactive protein, neutrophils, lactate dehydrogenase, albumin, (1-3)-β-D-glucan assay (BDG), and CD4⁺ T lymphocyte count were risk factors for CMV-PCP coinfection. Multivariate logistic regression analysis confirmed that lower PaO₂, albumin, and CD4⁺ T lymphocyte count were independent risk factors for CMV-PCP coinfection in AIDS patients. The patients with CMV-PCP coinfection showed significantly higher 28-day mortality (34.0%) than the patients without CMV coinfection (19.7%) (P < 0.05). Conclusions CMV-PCP coinfection is associated with a high morbidity and mortality in AIDS patients. Lower PaO₂, albumin, and CD4⁺ T lymphocyte count are independent risk factors for CMV-PCP coinfection. CMV-DNA screening is important for early diagnosis and treatment and so conducive to improving survival rate.