Predictive value of thrombocytopenia for bloodstream infection in patients with sepsis and septic shock

BACKGROUND Thrombocytopenia is common in patients with sepsis and septic shock.AIM To analyse the decrease in the number of platelets for predicting bloodstream infection in patients with sepsis and septic shock in the intensive care unit.METHODS A retrospective analysis of patients admitted with sepsis and septic shock in Xingtai People Hospital was revisited.Patient population characteristics and laboratory data were collected for analysis.RESULTS The study group consisted of 85(39%)inpatients with bloodstream infection,and the control group consisted of 133(61%)with negative results or contamination.The percentage decline in platelet counts(PPCs)in patients positive for pathogens[57.1(41.3-74.6)]was distinctly higher than that in the control group[18.2(5.1–43.1)](P<0.001),whereas the PPCs were not significantly different among those with gram-positive bacteraemia,gram-negative bacteraemia,and fungal infection.Using receiver operating characteristic curves,the area under the curve of the platelet drop rate was 0.839(95%CI:0.783-0.895).CONCLUSION The percentage decline in platelet counts is sensitive in predicting bloodstream infection in patients with sepsis and septic shock.However,it cannot identify gram-positive bacteraemia,gram-negative bacteraemia,and fungal infection.

重度烧伤患者发生中心静脉导管相关性血流感染的危险因素分析

目的分析重度烧伤患者深静脉置管后发生中心静脉导管相关性血流感染(CLABSI)的相关危险因素。方法选取2020年1月至2023年1月中国人民解放军联勤保障部队第九六〇医院收治的66例进行深静脉置管的重度烧伤患者作为研究对象,收集患者性别、年龄、烧伤总面积、有无吸入性损伤、有无营养不良、是否使用烧伤治疗床、导管留置部位、导管留置时间、置管部位有无创面以及感染情况等相关资料,并根据是否发生CLABSI将其分为发生组和未发生组,分析重度烧伤患者深静脉置管后发生CLABSI的相关危险因素。结果66例进行深静脉置管的重度烧伤患者中17例(25.76%)发生CLABSI,设为发生组;49例(74.24%)未发生CLABSI,设为未发生组。发生组有营养不良、导管留置部位为股静脉、置管部位有创面的患者明显多于未发生组(χ2=8.848、16.903、5.126,P=0.003、P<0.001、P=0.024)。多因素Logistic回归分析结果显示,有营养不良、导管留置部位为股静脉是重度烧伤患者深静脉置管后发生CLABSI的独立危险性因素(95%CI为1.233~23.741、0.015~0.435,P=0.025、0.003)。结论营养状态、导管留置部位与重度烧伤患者深静脉置管后CLABSI的发生密切相关。

孕产妇血流感染病原菌特点与抗感染方案分析

目的为制订血流感染孕产妇的药物治疗方案提供参考。方法回顾性分析徐州医科大学附属医院产科2017年1月至2022年6月收治的57例血流感染孕产妇的临床资料,分析患者的临床特征、抗菌药物治疗方案、血培养分离菌株分布及主要致病菌的药物敏感性试验结果。结果均采用抗菌药物治疗;住院期间静脉使用抗菌药物疗程3~30 d,中位疗程9(7,12)d;联合用药42例(73.68%);57例患者的体温及炎性因子水平指标均有升高;血培养分离菌株62株,大肠埃希菌占比最高(59.68%),其次为肠球菌属(17.74%)和链球菌属(11.29%)。药物敏感性试验结果显示,大肠埃希菌对哌拉西林他唑巴坦、头孢哌酮舒巴坦、亚胺培南、美罗培南的敏感率为100.00%,肠球菌对氨苄西林的敏感率为81.82%。结论孕产妇血流感染以大肠埃希菌较常见,结合药物适应证可选择哌拉西林他唑巴坦、头孢哌酮舒巴坦或碳青霉烯类抗菌药物单药治疗,必要时可联合用药。

血小板参数联合炎症因子指标在革兰阴性菌血流感染早期诊断中的应用

目的:探讨血小板参数联合炎症因子指标在早期诊断革兰阴性(GN)菌血流感染中的作用。方法:以2023年6—9月南京市高淳人民医院诊治的59例血流感染患者为试验组,其中GN菌感染37例(GN组),革兰阳性(GP)菌感染22例(GP组);选取同期20例健康患者为对照组。统计比较三组血小板参数[血小板计数(PLT)、血小板压积(PCT)、血小板分布宽度(PDW)、平均血小板体积(MPV)和炎症因子[白细胞介素-6(IL-6)、C反应蛋白(CRP)],分析血小板参数和炎症指标对GN菌的诊断价值。结果:GP组、GN组PCT、PDW和MPV均显著高于对照组,且GN组高于GP组,差异有统计学意义(P<0.05);GN组、GP组PLT低于对照组,且GN组PLT低于GP组,差异有统计学意义(P<0.05)。GP和GN组IL-6和CRP水平均高于对照组,GN组IL-6水平低于GP组,CRP水平高于和GP组,差异有统计学意义(P<0.05)。受试者工作特征(ROC)曲线分析显示,PLT、PCT、PDW、MPV、IL-6和CRP诊断GN菌感染的AUC值分别为0.676、0.754、0.585、0.590、0.622和0.665,而联合检查的AUC最高,为0.923(P<0.05)。结论:血小板参数联合炎症指标对检测GN菌血流感染具有一定的诊断价值。

Antimicrobial-impregnated catheters for the prevention of catheter-related bloodstream infections

Central venous catheters are commonly used in critically ill patients. Such catheterization may entail mechanica and infectious complications. The interest in catheterrelated infection lies in the morbidity, mortality and costs that it involved. Numerous contributions have been made in the prevention of catheter-related infection and the current review focuses on the possible current role of antimicrobial impregnated catheters to reduce catheter-related bloodstream infections(CRBSI). There is evidence that the use of chlorhexidine-silver sulfadiazine(CHSS), rifampicin-minocycline, or rifampicin-miconazol impregnated catheters reduce the incidence of CRBSI and costs. In addition, there are some clinical circumstances associated with higher risk of CRBSI, such as the venous catheter access and the presence of tracheostomy. Current guidelines for the prevention of CRBSI recommended the use of a CHSS or rifampicin-minocycline impregnated catheter in patients whose catheter is expected to remain in place > 5 d and if the CRBSI rate has not decreased after implementation of a comprehensive strategy to reduce it.

Molecular Epidemiology and Risk Factors of Carbapenem-Resistant Klebsiella Pneumoniae Bloodstream Infections in Wuhan,China

Objective:The clinical characteristics and microbiological data of patients with K.pneumoniae bloodstream infections(BSI)from January 2018 to December 2020 were retrospectively analyzed to study the molecular epidemiology of Carbapenem-resistant Klebsiella pneumoniae(CRKP).We also aimed to identify the risk factors for the development of CRKP BSI.Methods:This retrospective study was conducted at Renmin Hospital of Wuhan University from January 2018 to December 2020.The date of non-duplicate K.pneumoniae isolates isolated from blood samples was identified using the microbiology laboratory database.The data from patients diagnosed with K.pneumoniae BSI were collected and analyzed.

Central line-associated bloodstream infection among children with biliary atresia listed for liver transplantation

BACKGROUND Pre-transplant nutrition is a key driver of outcomes following liver transplantation in children.Patients with biliary atresia(BA) may have difficulty achieving satisfactory weight gain with enteral nutrition alone,and parenteral nutrition(PN) may be indicated.While PN has been shown to improve anthropometric parameters of children with BA listed for liver transplantation,less is known about the risks,particularly infectious,associated with this therapy among this specific group of patients.AIM To describe the incidence,microbiology,and risk factors of central line-associated bloodstream infection(CLABSI) among children with BA listed for liver transplantation.METHODS Retrospective review of children aged ≤ 2-years of age with BA who were listed for primary liver transplantation at Texas Children's Hospital from 2008 through2015(n = 96).Patients with a central line for administration of PN(n = 63) were identified and details of each CLABSI event were abstracted.We compared the group of patients who experienced CLABSI to the group who did not,to determine whether demographic,clinical,or laboratory factors correlated with development of CLABSI.RESULTS Nineteen of 63 patients(30%,95%CI:19,43) experienced 29 episodes of CLABSI during 4800 line days(6.04 CLABSI per 1000 line days).CLABSI was predominantly associated with Gram-negative organisms(14/29 episodes,48%)including Klebsiella spp.,Enterobacter spp.,and Escherichia coli.The sole polymicrobial infection grew Enterobacter cloacae and Klebsiella pneumoniae.Grampositive organisms(all Staphylococcus spp.) and fungus(all Candida spp.)comprised 9/29(31%) and 6/29(21%) episodes,respectively.No demographic,clinical,or laboratory factors were significantly associated with an increased risk for the first CLABSI event in Cox proportional hazards regression analysis CONCLUSION There is substantial risk for CLABSI among children with BA listed for liver transplantation.No clinical,demographic,or laboratory factor we tested emerged as an independent predictor of CLABSI.While our data did not show an impact of CLABSI on the short-term clinical outcome,it would seem prudent to implement CLABSI reduction strategies in this population to the extent that each CLABSI event represents potentially preventable hospitalization,unnecessary healthcare dollar expenditures,and may exact an opportunity cost,in terms of missed allograft offers.

High mortality associated with gram-negative bacterial bloodstream infection in liver transplant recipients undergoing immunosuppression reduction

BACKGROUND Immunosuppression is an important factor in the incidence of infections in transplant recipient.Few studies are available on the management of immunosuppression(IS)treatment in the liver transplant(LT)recipients complicated with infection.The aim of this study is to describe our experience in the management of IS treatment during bacterial bloodstream infection(BSI)in LT recipients and assess the effect of temporary IS withdrawal on 30 d mortality of recipients presenting with severe infection.AIM To assess the effect of temporary IS withdrawal on 30 d mortality of LT recipients presenting with severe infection.METHODS A retrospective study was conducted with patients diagnosed with BSI after LT in the Department of Liver Surgery,Renji Hospital from January 1,2016 through December 31,2017.All recipients diagnosed with BSI after LT were included.Univariate and multivariate Cox regression analysis of risk factors for 30 d mortality was conducted in the LT recipients with Gram-negative bacterial(GNB)infection.RESULTS Seventy-four episodes of BSI were identified in 70 LT recipients,including 45 episodes of Gram-positive bacterial(GPB)infections in 42 patients and 29 episodes of GNB infections in 28 patients.Overall,IS reduction(at least 50%dose reduction or cessation of one or more immunosuppressive agent)was made in 28(41.2%)cases,specifically,in 5(11.9%)cases with GPB infections and 23(82.1%)cases with GNB infections.The 180 d all-cause mortality rate was 18.5%(13/70).The mortality rate in GNB group(39.3%,11/28)was significantly higher than that in GPB group(4.8%,2/42)(P=0.001).All the deaths in GNB group were attributed to worsening infection secondary to IS withdrawal,but the deaths in GPB group were all due to graft-versus-host disease.GNB group was associated with significantly higher incidence of intra-abdominal infection,IS reduction,and complete IS withdrawal than GPB group(P<0.05).Cox regression showed that rejection(adjusted hazard ratio 7.021,P=0.001)and complete IS withdrawal(adjusted hazard ratio 12.65,P=0.019)were independent risk factors for 30 d mortality in patients with GNB infections after LT.CONCLUSION IS reduction is more frequently associated with GNB infection than GPB infection in LT recipients.Complete IS withdrawal should be cautious due to increased risk of mortality in LT recipients complicated with BSI.

Bloodstream Infections Caused by Enterococcus spp：A 10-year Retrospective Analysis at a Tertiary Hospital in China

In order to discover the risk factors for 30-day mortality in bloodstream infections（BSI） caused by Enterococcus spp.strains,we explored the clinical and therapeutic profile of patients with Enterococcus spp.BSI and the characteristics of this condition.A total of 64 patients with BSI caused by Enterococcus spp.who were treated in our hospital between 2006 and 2015 were included in the study.The clinical features of patients,microbiology,and 30-day mortality were collected from the electronic medical records database and analyzed.The results showed that there were 38 patients infected by Enterococcus faecalis（E.faecalis）,24 by Enterococcus faecium（E.faecium）,1 by Enterococcus casseliflavus（E.casseliflavus）,and 1 by Enterococcus gallinarum（E.gallinarum）.A Charlson comorbidity score ≥5,corticosteroid treatment,placement of catheters or other prosthetic devices and history of antibiotic use were found more frequently in E.faecium BSI patients than in E.faecalis patients（P=0.017,P=0.027,P=0.008 and P=0.027,respectively）.Furthermore,the univariate and multivariate analysis showed that corticosteroid treatment（OR=17.385,P=0.008）,hospital acquisition（OR=16.328,P=0.038）,and vascular catheter infection（OR=14.788,P=0.025） were all independently associated with 30-day mortality.Our results indicate that E.faecalis and E.faecium are two different pathogens with unique microbiologic characteristics,which cause different clinical features in BSI,and the empiric antimicrobial treatments are paramount for patients with enterococcal BSI.

Bloodstream Infection with Carbapenem-resistant Klebsiella Pneumoniae and Multidrug-resistant Acinetobacter Baumannii:a Case Report

IN the presence of septic shock, every hour in delaying the administration of effective antibiotics is associated with a measurable increase in mortality. This is especially true for neutropenic patients with septic shock. As there is a higher incidence of involving multi-drug resistant pathogens for neutropenic patients, the decision on antibiotics regime remains a challenge for physicians.2 Immunosuppression and previous antibacterial use are factors that promote the spread of multi-drug resistant pathogens, and the possibility of co-existing multi-drug resistant pathogens should be suspected when treating patients with these risk factors who developed refractory shock. Here we present a case with neutropenic fever and refractory shock whose blood culture yielded multi-drug resistant Acinetobacter baumannii and carbapenem- resistant Klebsiella pneumoniae.

Development and validation of an emergency bloodstream infection score for predicting in-hospital mortality in patients with community-acquired bloodstream infections

BACKGROUND:Community-acquired bloodstream infections(CABSIs)are common in the emergency departments,and some progress to sepsis and even lead to death.However,limited information is available regarding the prediction of patients with high risk of death.METHODS:The Emergency Bloodstream Infection Score(EBS)for CABSIs was developed to visualize the output of a logistic regression model and was validated by the area under the curve(AUC).The Mortality in Emergency Department Sepsis(MEDS),Pitt Bacteremia Score(PBS),Sequential Organ Failure Assessment(SOFA),quick Sequential Organ Failure Assessment(qSOFA),Charlson Comorbidity Index(CCI),and McCabe–Jackson Comorbid Classification(MJCC)for patients with CABSIs were computed to compare them with EBS in terms of the AUC and decision curve analysis(DCA).The net reclassification improvement(NRI)index and integrated discrimination improvement(IDI)index were compared between the SOFA and EBS.RESULTS:A total of 547 patients with CABSIs were included.The AUC(0.853)of the EBS was larger than those of the MEDS,PBS,SOFA,and qSOFA(all P<0.001).The NRI index of EBS in predicting the in-hospital mortality of CABSIs patients was 0.368(P=0.04),and the IDI index was 0.079(P=0.03).DCA showed that when the threshold probability was<0.1,the net benefit of the EBS model was higher than those of the other models.CONCLUSION:The EBS prognostic models were better than the SOFA,qSOFA,MEDS,and PBS models in predicting the in-hospital mortality of patients with CABSIs.

Serum Cholesterol Levels at the Onset of Bloodstream Infection Have Prognostic Value

Objective: The aims of this study were to investigate the changes in serum cholesterol levels at the onset of bloodstream infection (BSI) and to determine whether serum cholesterol levels were associated with patients’ clinical backgrounds and the prognosis of BSI;Methods: A retrospective chart review was done to collect demographic information and the subjects’ medical history, invasive procedures, and medications;Patients and Methods: From April 2003 to March 2006, all patients aged ≥20 years with positive blood cultures in the University of Tokyo Hospital (a tertiary teaching hospital with 1200 beds) were enrolled;Results: Average cholesterol levels before the onset of BSI were 166.5 ± 46.5 mg/dL, and, at the onset of BSI, they decreased to 134.4 ± 45.0 mg/dL (p < 0.001). Thirty-day survivors had higher cholesterol levels both before and at the onset of BSI than non-survivors. Cholesterol levels at the onset of BSI were associated with the organisms of BSI. Patients with lower cholesterol levels tended to have higher 30-day mortality rates and longer medical treatment than patients with higher cholesterol levels (13% vs 3%, p = 0.12;24.3 days vs 18.4 days, p = 0.15);Conclusion: Cholesterol levels at the onset of BSI could be used as a prognostic marker in patients with BSI.

Cefoperazone-sulbactam and ornidazole for Gardnerella vaginalis bloodstream infection after cesarean section:A case report

BACKGROUND Gardnerella vaginalis(G.vaginalis)is a facultative anaerobic bacteria known to cause bloodstream infections.However,cases are very rare in clinics.There is very limited clinical experience in the treatment of bloodstream infections caused by G.vaginalis.Therefore,there is an urgent need for effective antibacterial drugs to treat patients with bloodstream infections caused by G.vaginalis.CASE SUMMARY A woman who underwent a cesarean section presented with a sudden onset of high fever 1-d post-surgery.The blood cultures suggested an infection due to G.vaginalis,and treatment with cefoperazone-sulbactam was started.After 5 d of treatment,there was a decrease in the hemogram;however,the temperature and C-reactive protein levels remained high.Based on clinical experience and a review of literature,the treatment was modified to include ornidazole in combination with cefoperazone-sulbactam.Following a week of treatment,the temperature,hemogram and C-reactive protein levels returned to normal,and blood cultures turned negative,suggesting a therapeutic effect of the combination treatment.CONCLUSION This case highlighted the effective use of cefoperazone-sulbactam combined with ornidazole for bloodstream infection caused by G.vaginalis following a cesarean section.

Ethanol Lock Therapy as additional treatment of catheter-related bloodstream infections in pediatric patients receiving home parenteral nutrition

Background: Catheter related bloodstream infections (CRIs) are a major cause of morbidity, mortality and prolonged hospitalization in pediatric patients with home parenteral nutrition (HPN). In recent years, new prophylactic and treatment options have been evaluated to reduce the incidence of CRIs and infection related catheter removals. In children, two retrospective studies have shown the efficacy of ethanol lock treatment (ELT) in reducing the incidence of CRIs in pediatric oncology patients. However, prospective data are missing. Our aim of the present study was to evaluate prospectively the effect of ELT on the cure and recurrence rate of CRIs, duration of hospitalization and antibiotic use in HPN pediatric patients. Methods: HPN children older than three months with a clinical suspicion of a CRI were included and randomised to ELT or standard flushing treatment (heparin or taurolidine). The primary outcomes were persistence and recurrence of the bacteraemia and Central Venous Access Device (CVAD) removal. Secondary outcomes included duration of antibiotic use, duration of hospitalization and side effects. Results: Data from eight HPN children experiencing 14 suspected CRI were analysed. Seven patients had proven CRIs by positive blood cultures. Four were treated with ELT and three with their standard flushing treatment. One CRI persisted in the control group. In one single patient, bacteraemia recurred three times within 24 weeks. This patient had been enrolled in both study arms. A CVAD removal was needed in one patient because of occlusion. Conclusions: This small study showed no additional efficacy of the use of ELT on cure rate or recurrences of CRIs compared to standard therapy in HPN treated children. There were also no differences in duration of hospitalization, the use of antibiotics or CVAD removal between both groups.

Central Line Associated Bloodstream Infection in Adult Intensive Care Unit Population—Changes in Epidemiology, Diagnosis, Prevention, and Addition of New Technologies

Background: Intensive care units (ICUs) have an increased risk of Central line associated bloodstream infection (CLABSI) due to the prevalence of invasive procedures, devices, immunosuppression, comorbidity, frailty, and elderly patients. We have seen a successful reduction in Central line associated bloodstream infection related the past decade. In spite of this, Intensive care unit-Catheter related bloodstream infections remain high. The emergence of new pathogens further complicates treatment and threatens patient outcomes in this context. In addition, the SARS-CoV-2 (COVID-19) pandemic served as a reminder that an emerging pathogen poses a challenge for adjusting prevention measures regarding both the risk of exposure to caregivers and maintaining a high level of care. ICU nurses play an important role in the prevention and management of CLABSI as they are involved in basic hygienic care, quality improvement initiatives, microbiological sampling, and aspects of antimicrobial stewardship. Microbiological techniques that are more sensitive and our increased knowledge of the interactions between critically ill patients and their microbiota are forcing us to rethink how we define CLABSIs and how we can diagnose, treat, and prevent them in the ICU. The objective of this multidisciplinary expert review, focused on the ICU setting, is to summarize the recently observed occurrence of CLABSI in ICU, to consider the role of modern microbiological techniques in their diagnosis, to examine clinical and epidemiological definitions, and to redefine several controversial preventive measures including antimicrobial-impregnated catheters, chlorhexidine-gluconate impregnated sponge, and catheter dressings.

Assessment of pathogens and risk factors associated with bloodstream infection in the year after pediatric liver transplantation

BACKGROUND Bloodstream infection(BSI)is one of the most significantly adverse events that can occur after liver transplantation(LT)in children.AIM To analyze the profile of BSI according to the postoperative periods and assess the risk factors after pediatric LT.METHODS Clinical data,collected from medical charts of children(n=378)who underwent primary LT,were retrospectively reviewed.The primary outcome considered was BSI in the first year after LT.Univariate and multivariate analyses were performed to identify risk factors for BSI and respective odds ratios(ORs).RESULTS Of the examined patients,106(28%)experienced 162 episodes of pathogen-confirmed BSI during the first year after LT.There were 1.53±0.95 episodes per children(mean±SD)among BSIcomplicated patients with a median onset of 0.4 mo post-LT.The most common pathogenic organisms identified were Coagulase-negative staphylococci,followed by Enterococcus spp.and Streptococcus spp.About half(53%)of the BSIs were of unknown origin.Multivariate analysis demonstrated that young age(≤1.3 year;OR=2.1,P=0.011),growth failure(OR=2.1,P=0.045),liver support system(OR=4.2,P=0.008),and hospital stay of>44 d(OR=2.3,P=0.002)were independently associated with BSI in the year after LT.CONCLUSION BSI was frequently observed in patients after pediatric LT,affecting survival outcomes.The profile of BSI may inform clinical treatment and management in high-risk children after LT.

APPROACH OF IMPROVING PRECISION IN ULTRASONIC DOPPLER BLOODSTREAM SPEED MEASUREMENT BY CHAOS-BASED FREQUENCY DETECTING

It is critical for cerebral vascular disease diagnosis through Doppler to detect the maximum and the minimum of the carotid blood flow speed accurately. A kind of Duffing system under an external periodic power with dump is introduced in the letter, numerical analysis is carried out by four-order Runge-Kutta method. An oscillator array is designed according to the frequency of the ultrasonic wave. When the external signals are inputted, computational algorithm is used to scan the array in turn and analyze the result, and the frequency can be determined. Based on the methods above, detecting the carotid blood flow speed accurately is realized. The Signal-to-Noise Ratio (SNR) of-20.23dB is obtained by the result of experiments. In conclusion, the SNR has been improved and the precision of the measured bloodstream speed has been increased, which can be 0.069% to 0.13%.

Investigation and Analysis of the Status Quo of Prevention and Control Practices of Catheter-Line Associated Bloodstream Infections (CLABSI) in Guangxi, China

The prevention and control of catheter line-associated bloodstream infections (CLABSI) have become the key content of medical care and have become the core improvement goal of nursing quality control. However, the prevention and control status of CLABSI in hospitals of different grades in Guangxi is not clear. In this study, we aim to investigate central venous catheter (CVC) placement and disinfectant use in second and third-level hospitals in Guangxi. This survey was conducted on the second and third-level hospitals in Guangxi, China from 13th April 2021 to 19th April 2021. The results show that a total of 283 questionnaires were collected, including 206 secondary hospitals and 77 tertiary hospitals. In terms of the CVC, tertiary hospitals were able to place CVC entirely under the guidance of B-ultrasound, which was 24 (31.6%) and secondary hospitals were 26 (20.6%). In secondary hospitals, Most CVC placements were performed in operating rooms 94 (74.6%) and 65 (85.5%) on the third level hospital, but 32.5% of secondary hospitals and 48.7% of tertiary hospitals were selected at the bedside of patients in general wards, and 27.8% of the second-level hospital, 43.4% of third-level hospitals was done in general ward treatment rooms, only 61.9% of secondary hospitals and 64.5% of tertiary hospitals could fully achieve the maximum sterile barrier. In terms of skin disinfectants, only 36.0% of tertiary hospitals and 16.4% of second-level CVC-operators chose > 0.5% chlorhexidine alcohol. In conclusion, the prevention and control of catheter line-associated bloodstream infections (CLABSI) in Guangxi are not ideal. The prevention and control department should increase training, implement guidelines and standardize management to reduce the incidence of CLABSI.

Review of the Clinical Applications of Metagenomic Next-Generation Sequencing in Bloodstream Infection

Bloodstream infection (BSI) is an important cause of morbidity and mortality worldwide. If we can make early diagnosis and start effective antibiotic treatment in time, the hospitalization time of patients with bloodstream infection can be significantly shortened. However, the current diagnosis of bloodstream infection cannot achieve the ideal therapeutic effect to a large extent because of the matrix effect of blood and the long turnaround time of blood culture. Therefore, a new detection method with a short turnaround time and high sensitivity is needed for the early diagnosis and timely treatment to improve the prognosis of patients. Metagenomic next-generation sequencing (mNGS) is a recently developed method for the comprehensive analysis of all microorganisms and genetic materials in clinical samples and is expected to be the main method for the early diagnosis of bloodstream infections. This review discusses the clinical application of mNGS in bloodstream infections. We also discuss technical challenges that need to be addressed to improve the diagnostic applicability of mNGS.

Fatal community-acquired bloodstream infection caused by Klebsiella variicola:A case report

BACKGROUND Klebsiella pneumoniae(K.pneumoniae)is an infective microorganism of worldwide concern because of its varied manifestations and life-threatening potential.Genetic analyses have revealed that subspecies of K.pneumoniae exhibit higher virulence and mortality.However,infections with Klebsiella subspecies are often misdiagnosed and underestimated in the clinic because of difficulties in distinguishing K.pneumoniae from its subspecies using routine tests.This case study reports the rapid and fatal effects of K.pneumoniae subspecies.CASE SUMMARY A 52-year-old male patient was febrile and admitted to hospital.Examinations excluded viral and fungal causes along with mycoplasma/chlamydia and parasitic infections.Bacterial cultures revealed blood-borne K.pneumoniae sensitive to carbapenem antibiotics,although corresponding treatment failed to improve the patient’s symptoms.His condition worsened and death occurred within 72 h of symptom onset from sepsis shock.Application of the PMseq-DNA Pro high throughput gene detection assay was implemented with results obtained after death showing a mixed infection of K.pneumoniae and Klebsiella variicola(K.variicola).Clinical evidence suggested that K.variicola rather than K.pneumoniae contributed to the patient’s poor prognosis.CONCLUSION This is the first case report to show patient death from Klebsiella subspecies infection within a short period of time.This case provides a timely reminder of the clinical hazards posed by Klebsiella subspecies and highlights the limitations of classical laboratory methods in guiding anti-infective therapies for complex cases.Moreover,this report serves as reference for physicians diagnosing similar diseases and provides a recommendation to employ early genetic detection to aid patient diagnosis and management.