Oxygen vacancy boosting Fenton reaction in bone scaffold towards fighting bacterial infection

Bacterial infection is a major issue after artificial bone transplantation due to the absence of antibacterial function of bone scaffold,which seriously causes the transplant failure and even amputation in severe cases.In this study,oxygen vacancy(OV)defects Fe-doped Ti O2(OV-FeTiO2)nanoparticles were synthesized by nano TiO2and Fe3O4via high-energy ball milling,which was then incorporated into polycaprolactone/polyglycolic acid(PCLGA)biodegradable polymer matrix to construct composite bone scaffold with good antibacterial activities by selective laser sintering.The results indicated that OV defects were introduced into the core/shell-structured OV-FeTiO2nanoparticles through multiple welding and breaking during the high-energy ball milling,which facilitated the adsorption of hydrogen peroxide(H2O2)in the bacterial infection microenvironment at the bone transplant site.The accumulated H2O2could amplify the Fenton reaction efficiency to induce more hydroxyl radicals(·OH),thereby resulting in more bacterial deaths through·OH-mediated oxidative damage.This antibacterial strategy had more effective broad-spectrum antibacterial properties against Gram-negative Escherichia coli(E.coli)and Gram-positive Staphylococcus aureus(S.aureus).In addition,the PCLGA/OV-FeTiO2scaffold possessed mechanical properties that match those of human cancellous bone and good biocompatibility including cell attachment,proliferation and osteogenic differentiation.

Improving treatment plan and mental health in children with abdominal infection for broad-spectrum bacterial infections

BACKGROUND Pediatric abdominal infection is a common but serious disease that requires timely and effective treatment.In surgical treatment,accurate diagnosis and rational application of antibiotics are the keys to improving treatment effects.AIM To investigate the effect of broad-spectrum bacterial detection on postoperative antibiotic therapy.METHODS A total of 100 children with abdominal infection who received surgical treatment in our hospital from September 2020 to July 2021 were grouped.The observation group collected blood samples upon admission and sent them for broad-spectrum bacterial infection nucleic acid testing,and collected pus or exudate during the operation for bacterial culture and drug sensitivity testing;the control group only sent bacterial culture and drug sensitivity testing during the operation.RESULTS White blood cell count,C-reactive protein,procalcitonin,3 days after surgery,showed better postoperative index than the control group(P<0.05).The hospital stay in the observation group was significantly shorter than that in the control group.The hospitalization cost in the observation group was significantly lower than that in the control group,and the difference between the two groups was statistically significant(P<0.05).CONCLUSION Early detection of broad-spectrum bacterial infection nucleic acids in pediatric abdominal infections can help identify pathogens sooner and guide the appropriate use of antibiotics,improving treatment outcomes and reducing medical costs to some extent.

Retrospective study of the incidence, risk factors, treatment outcomes of bacterial infections at uncommon sites in cirrhotic patients

BACKGROUND Bacterial infections(BI)negatively affect the natural course of cirrhosis.The most frequent BI are urinary tract infections(UTI),pneumonia,and spontaneousbacterial peritonitis(SBP).AIM To assess the relevance of bacterial infections beyond the commonly recognized types in patients with cirrhosis and to investigate their relationship with other clinical variables.METHODS We retrospectively analyzed patients with cirrhosis and BI treated between 2015 and 2018 at our tertiary care center.BIs were classified as typical and atypical,and clinical as well as laboratory parameters were compared between the two groups.RESULTS In a cohort of 488 patients with cirrhosis,we identified 225 typical BI(95 UTI,73 SBP,72 pulmonary infections)and 74 atypical BIs,predominantly cholangitis and soft tissue infections(21 each),followed by intra-abdominal BIs(n=9),cholecystitis(n=6),head/throat BIs(n=6),osteoarticular BIs(n=5),and endocarditis(n=3).We did not observe differences concerning age,sex,or etiology of cirrhosis in patients with typical vs atypical BI.Atypical BIs were more common in patients with more advanced cirrhosis,as evidenced by Model of End Stage Liver Disease(15.1±7.4 vs 12.9±5.1;P=0.005)and Child-Pugh scores(8.6±2.5 vs 8.0±2;P=0.05).CONCLUSION Atypical BIs in cirrhosis patients exhibit a distinct spectrum and are associated with more advanced stages of the disease.Hence,the work-up of cirrhosis patients with suspected BI requires detailed work-up to elucidate whether typical BI can be identified.

Rice Bacterial Infection Detection Using Ensemble Technique on Unmanned Aerial Vehicles Images

Establishing a system for measuring plant health and bacterial infection is critical in agriculture.Previously,the farmers themselves,who observed them with their eyes and relied on their experience in analysis,which could have been incorrect.Plant inspection can determine which plants reflect the quantity of green light and near-infrared using infrared light,both visible and eye using a drone.The goal of this study was to create algorithms for assessing bacterial infections in rice using images from unmanned aerial vehicles(UAVs)with an ensemble classification technique.Convolution neural networks in unmanned aerial vehi-cles image were used.To convey this interest,the rice’s health and bacterial infec-tion inside the photo were detected.The project entailed using pictures to identify bacterial illnesses in rice.The shape and distinct characteristics of each infection were observed.Rice symptoms were defined using machine learning and image processing techniques.Two steps of a convolution neural network based on an image from a UAV were used in this study to determine whether this area will be affected by bacteria.The proposed algorithms can be utilized to classify the types of rice deceases with an accuracy rate of 89.84 percent.

Selective intestinal decontamination for the prevention of early bacterial infections after liver transplantation

Bacterial infection in the first month after liver transplantation is a frequent complication that poses a serious risk for liver transplant recipients as contributes substantially to increased length of hospitalization and hospital costs being a leading cause of death in this period. Most of these infections are caused by gramnegative bacilli, although gram-positive infections, especially Enterococcus sp. constitute an emerging infectious problem. This high rate of early postoperative infections after liver transplant has generated interest in exploring various prophylactic approaches to surmount this problem. One of these approaches is selective intestinal decontamination(SID). SID is a prophylactic strategy that consists of the administration of antimicrobials with limited anaerobicidal activity in order to reduce the burden of aerobic gram-negative bacteria and/or yeast in the intestinal tract and so prevent infections caused by these organisms. The majority of studies carried out to date have found SID to be effective in the reduction of gram-negative infection, but the effect on overall infection is limited due to a higher number of infection episodes by pathogenic enterococci and coagulase-negative staphylococci. However, difficulties in general extrapolation of the favorable results obtained in specific studies together with the potential risk of selection of multirresistant microorganisms has conditioned controversy about the routinely application of these strategies in liver transplant recipients.

Bacterial infections in cirrhotic patients with hepatocellular carcinoma

AIMS To establish the prevalence of bacterial infection in cir- rhotic patients with hepatocellular carcinoma(HCC). METHODS All 719 cirrhotic patients with HCC were investigat- ed retrospectively for the prevalence of bacterial infections. RESULTS The incidence of bacterial infection was 15.4% (111/719).According to Child-Pugh classification,the inci- dences of bacterial infection in class A,B and C were 2.3%,8. 0%,and 26.4 %,respectively.The bacterial infection increased with the severity of cirrhosis and severe bacterial infections usual- ly occurred in Child-Pugh class B and C patients. CONCLUSIONS The susceptibility of HCC patients to bacterial infection is mainly due to the underlying cirrhosis and not to the HCC itself.

Bacterial infection after liver transplantation

Infectious complications are major causes of morbidity and mortality after liver transplantation,despite recent advances in the transplant field.Bacteria,fungi,viruses and parasites can cause infection before and after transplantation.Among them,bacterial infections are predominant during the first two months posttransplantation and affect patient and graft survival.They might cause surgical site infections,including deep intra-abdominal infections,bacteremia,pneumonia,catheter-related infections and urinary tract infections.The risk factors for bacterial infections differ between the periods after transplant,and between centers.Recently,the emergence of multi-drug resistant bacteria is great concern in liver transplant(LT)patients.The instructive data about effects of infections with extended-spectrum beta lactamase producing bacteria,carbapenem-resistant gram-negative bacteria,and glycopeptide-resistant gram-positive bacteria were reported on a center-by-center basis.To prevent posttransplant bacterial infections,proper strategies need to be established based upon center-specific data and evidence from well-controlled studies.This article reviewed the recent epidemiological data,risk factors for each type of infections and important clinical issues in bacterial infection after LT.

Multidrug-resistant bacterial infections after liver transplantation: An ever-growing challenge

Bacterial infections are a leading cause of morbidity and mortality among solid organ transplant recipients.Over the last two decades,various multidrug-resistant(MDR)pathogens have emerged as relevant causes of infection in this population.Although this fact reflects the spread of MDR pathogens in health care facilities worldwide,several factors relating to the care of transplant donor candidates and recipients render these patients particularly prone to the acquisition of MDR bacteria and increase the likelihood of MDR infectious outbreaks in transplant units.The awareness of this high vulnerability of transplant recipients to infection leads to the more frequent use of broad-spectrum empiric antibiotic therapy,which further contributes to the selection of drug resistance.This vicious cycle is difficult to avoid and leads to a scenario of increased complexity and narrowed therapeutic options.Infection by MDR pathogens is more frequently associated with a failure to start appropriate empiric antimicrobial ther-apy.The lack of appropriate treatment may contribute to the high mortality occurring in transplant recipients with MDR infections.Furthermore,high therapeutic failure rates have been observed in patients infected with extensively-resistant pathogens,such as carbapenemresistant Enterobacteriaceae,for which optimal treatment remains undefined.In such a context,the careful implementation of preventive strategies is of utmost importance to minimize the negative impact that MDR infections may have on the outcome of liver transplant recipients.This article reviews the current literature regarding the incidence and outcome of MDR infections in liver transplant recipients,and summarizes current preventive and therapeutic recommendations.

Update and actual trends on bacterial infections following liver transplantation

Recent advances in effective antimicrobial prophylactic strategies have led to a decline in the incidence of opportunistic infections in liver transplant recipients. However, morbidity and mortality due to infectious diseases remain as major problems. Bacterial infections occurring early after transplant are mainly related to the technical aspects of the procedure. By contrast, after the first postoperative days and beyond, the nature and variety of infectious complications change. Opportunistic bacterial infections are uncommon after 6 mo in patients receiving stable and reduced maintenance doses of immunosuppression with good graft function and little is documented about these cases in the literature. Transplant recipients may be more susceptible to some pathogens, such as the Nocardia species, Legionella species, Listeria monocytogenes , Mycoplasma species, Salmonella species or Rhodococcus equi. Respiratory infections due to capsulated bacteria, such as Streptococcus pneumoniae and Haemophilus intTuenza, can be life- threatening if not promptly treated in this population. These late bacterial infections may be very difficult to recognize and treat in this population. In this article, we review what has been described in the literature with regards to late bacterial infections following liver transplantation.

Bacterial infection triggers and complicates acute-on-chronic liver failure in patients with hepatitis B virus-decompensated cirrhosis: A retrospective cohort study

BACKGROUND Reports on bacterial infection(BI)in decompensated cirrhosis(DC)is mainly from alcoholic cirrhosis.The role of BI as a trigger or complication of acute-onchronic liver failure(ACLF)in patients with hepatitis B virus decompensated cirrhosis(HBV-DC)remains to be investigated.AIM To investigate the impact of BI on the outcomes of the patients with HBV-DC admitted into the hospital with or without ACLF.METHODS This retrospective study included patients with HBV-DC admitted to two tertiary centers in China.In-hospital overall survival,90-d transplant-free survival,5-year post-discharge survival,and cumulative incidence of ACLF were evaluated.Risk factors for death were analyzed considering liver transplantation as a competing event.RESULTS A total of 1281 hospitalized HBV-DC patients were included;284 had ACLF at admission.The overall prevalence of BI was 28.1%.The patients with BI had a significantly lower in-hospital survival and transplant-free 90-d survival than those without,in both the patients admitted with and without ACLF.The presence of BI significantly increased the risk of developing ACLF[subdistribution hazard ratio(sHR)=2.52,95%CI:1.75-3.61,P<0.001]in the patients without ACLF.In the patients discharged alive,those who had an episode of BI had a significantly lower 5-year transplant-free survival.BI was an independent risk factor for death in the patients admitted without ACLF(sHR=3.28,95%CI:1.93-5.57),while in ACLF admissions,the presence of pneumonia,but not other type of BI,independently increased the risk of death(sHR=1.87,95%CI:1.24-2.82).CONCLUSION BI triggers ACLF in patients with HBV-DC and significantly impairs short-term survival.HBV-DC patients should be monitored carefully for the development of BI,especially pneumonia,to avoid an adverse outcome.

Presepsin teardown- pitfalls of biomarkers in the diagnosis and prognosis of bacterial infection in cirrhosis

AIM To evaluate the diagnostic and prognostic value of presepsin in cirrhosis-associated bacterial infections. METHODS Two hundred and sixteen patients with cirrhosis were enrolled. At admission, the presence of bacterial infections and level of plasma presepsin, serum C-reactive protein(CRP) and procalcitonin(PCT) were evaluated. Patients were followed for three months to assess the possible association between presepsin level and short-term mortality.RESULTS Present 34.7 of patients had bacterial infection. Presepsin levels were significantly higher in patients with infection than without(median, 1002 pg/m L vs 477 pg/m L, P < 0.001), increasing with the severity of infection [organ failure(OF): Yes vs No, 2358 pg/m L vs 710 pg/m L, P < 0.001]. Diagnostic accuracy of presepsin for severe infections was similar to PCT and superior to CRP(AUC-ROC: 0.85, 0.85 and 0.66, respectively, P = NS for presepsin vs PCT and P < 0.01 for presepsin vs CRP). At the optimal cut-off value of presepsin > 1206 pg/m L sensitivity, specificity, positive predictive values and negative predictive values were as follows: 87.5%, 74.5%, 61.8% and 92.7%. The accuracy of presepsin, however, decreased in advanced stage of the disease or in the presence of renal failure, most probably because of the significantly elevated presepsin levels in non-infected patients. 28-d mortality rate was higher among patients with > 1277 pg/m L compared to those with ≤ 1277 pg/m L(46.9% vs 11.6%, P < 0.001). In a binary logistic regression analysis, however, only PCT(OR = 1.81, 95%CI: 1.09-3.01, P = 0.022) but neither presepsin nor CRP were independent risk factor for 28-d mortality after adjusting with MELD score and leukocyte count.CONCLUSION Presepsin is a valuable new biomarker for defining severe infections in cirrhosis, proving same efficacy as PCT. However, it is not a useful marker of short-term mortality.

Risk factors of intra-abdominal bacterial infection after liver transplantation in patients with hepatocellular carcinoma

Objective： To explore the risk factors of intra-abdominal bacterial infection （IAI） after liver transplantation （LT） in patients with hepatocellular carcinoma （HCC）. Methods： A series of 82 HCC patients who received LT surgeries in our department between March 2004 and April 2010 was recruited in this study. Then we collected and analyzed the clinical data retrospectively. Statistical analysis system （SPSS） software was adopted to perform statistical analysis. Chi-square test, t-test and Wilcoxon rank sum test were used to analyze the clinical data and compute the significance of the incidences of early-stage IAI after LT for HCC patients. Binary logistic regression was performed to screen out the risk factors, and multiple logistic regression analyses were performed to compute the independent risk factors. Results： A series of 13 patients （13/82, 15.9%） had postoperative IAI. The independent risk factors of postoperative intra-abdominal bacterial infections after LT for HCC patients were preoperative anemia [Hemoglobin （HGB） 〈90 g/L] and postoperative abdominal hemorrhage （72 hours 〉400 mL）, with the odds ratios at 8.121 （95% CI, 1.417 to 46.550, P=0.019） and 5.911 （95% CI, 1.112 to 31.432, P=0.037）. Conclusions： Postoperative IAI after LT in patients with HCC was a common complication. Preoperative moderate to severe anemia, as well as postoperative intra-abdominal hemorrhage more than 400 mL within the first 72 hours might independently indicate high risk of IAI for these patients.

Multiresistant bacterial infections in liver cirrhosis: Clinical impact and new empirical antibiotic treatment policies

Recently, important changes have been reported regarding the epidemiology of bacterial infections in liver cirrhosis. There is an emergence of multiresistant bacteria in many European countries and also worldwide, including the United States and South Korea. The classic empirical antibiotic treatment(third-generation cephalosporins, e.g., ceftriaxone, cefotaxime or amoxicillin-clavulanic acid) is still effective in infections acquired in the community, but its failure rate in hospital acquired infections and in some health-care associated infections is high enough to ban its use in these settings. The current editorial focuses on the different epidemiology of bacterial infections in cirrhosis across countries and on its therapeutic implications.

Studying host genetic background effects on multimorbidity of intestinal cancer development,type 2 diabetes and obesity in response to oral bacterial infection and high-fat diet using the collaborative cross(CC)lines

Background:Multimorbidity of intestinal cancer(IC),type 2 diabetes(T2D)and obesity is a complex set of diseases,affected by environmental and genetic risk factors.High-fat diet(HFD)and oral bacterial infection play important roles in the etiology of these diseases through inflammation and various biological mechanisms.Methods:To study the complexity of this multimorbidity,we used the collaborative cross(CC)mouse genetics reference population.We aimed to study the multimorbidity of IC,T2D,and obesity using CC lines,measuring their responses to HFD and oral bacterial infection.The study used 63 mice of both sexes generated from two CC lines(IL557 and IL711).For 12 weeks,experimental mice were maintained on specific dietary regimes combined with co-infection with oral bacteria Porphyromonas gingivalis and Fusobacterium nucleatum,while control groups were not infected.Body weight(BW)and results of a intraperitoneal glucose tolerance test(IPGTT)were recorded at the end of 12 weeks,after which length and size of the intestines were assessed for polyp counts.Results:Polyp counts ranged between 2 and 10 per CC line.The combination of HFD and infection significantly reduced(P<.01)the colon polyp size of IL557 females to 2.5 cm 2,compared to the other groups.Comparing BW gain,IL557 males on HFD gained 18 g,while the females gained 10 g under the same conditions and showed the highest area under curve(AUC)values of 40000-45000(min mg/dL)in the IPGTT.Conclusion:The results show that mice from different genetic backgrounds respond differently to a high fat diet and oral infection in terms of polyp development and glucose tolerance,and this effect is gender related.

New determinants of prognosis in bacterial infections in cirrhosis

Despite major advances in the knowledge and management of liver diseases achieved in recent decades,decompensation of cirrhosis still carries a high burden of morbidity and mortality.Bacterial infections are one of the main causes of decompensation.It is very important for clinical management to be aware of the population with the highest risk of poor outcome.This review deals with the new determinants of prognosis in patients with cirrhosis and bacterial infections reported recently.Emergence of multiresistant bacteria has led to an increasing failure rate of the standard empirical antibiotic therapy recommended by international guidelines.Moreover,it has been recently reported that endothelial dysfunction is associated with the degree of liver dysfunction and,in infected patients,with the degree of sepsis.It has also been reported that relative adrenal insufficiency is frequent in the non-critically ill cirrhotic population and it is associated with a higher risk of developing infection,severe sepsis,hepatorenal syndrome and death.We advise a change in the standard empirical antibiotic therapy in patients with high risk for multiresistant infections and also to take into account endothelial and adrenal dysfunction in prognostic models in hospitalized patients with decompensated cirrhosis.

Development of a novel score for the diagnosis of bacterial infection in patients with acute-on-chronic liver failure

BACKGROUND The diagnosis of bacterial infection is difficult in patients with acute-on-chronic liver failure(ACLF).AIM To evaluate the diagnostic accuracy of widely used parameters for bacterial infection in ACLF and to develop a simple scoring system to improve diagnostic efficiency.METHODS This was a retrospective study.Procalcitonin(PCT),white blood cells(WBC),proportion of neutrophils(N%),and C-reactive protein(CRP)were examined.Logistic regression was used to select variables for the scoring models and receiver operating characteristic curve(ROC)analysis was used to evaluate the diagnostic value of different indices.RESULTS This study included 386 patients with ACLF,169(43.78%)of whom had bacterial infection on admission.The area under the ROC(AUROC)of PCT,CRP,WBC and N%for the diagnosis of bacterial infection ranged from 0.637 to 0.692,with no significant difference between them.Logistic regression showed that only N%,PCT,and CRP could independently predict infection.A novel scoring system(infection score)comprised of N%,PCT and CRP was developed.The AUROC of the infection score was 0.740,which was significantly higher than that for the other four indices(infection score vs N%,PCT,CRP,and WBC,P=0.0056,0.0001,0.0483 and 0.0008,respectively).The best cutoff point for the infection score was 4 points,with a sensitivity of 78.05%,a specificity of 55.29%,a positive predictive value of 57.91%and a negative predictive value of 76.16%.CONCLUSION The infection score is a simple and useful tool for discriminating bacterial infection in ACLF.

Comparison on Serum Levels of Procalcitonin of Children with Viral and Bacterial Infection

Objective To compare and analyze serum levels of procalcitonin (PCT) of children with viral and bacterial infection and probe into the importance of determining the level of serum PCT in the diagnosis of bacterial infection in order to provide evidences of the clinical use of antibiotics. Methods A total of 85 cases of children with an average age of 8.9 years (10 months-12 years) were enrolled in this study, 53 cases were with viral infection and 32 cases with bacterial infection. We determined serum levels of PCT by semi-quantitative solid phase immunoassay, and the serum levels of PCT were divided into four grades as<0.5μg/L,≥ 0.5μg/L,≥2.0μg/L and≥10μg/L forχ2 test and Ridit analysis. Results The serum level of PCT of the group with bacterial infection were signiifcantly higher than that of the group with viral infection (P<0.001). The sensitivity of diagnosis of bacterial infection in children with determination of serum levels of PCT was 87.50%while the speciifcity was 92.13%, and positive predictive value was 73.68%while negative predictive value was 91.49%, and positive likelihood ratio was 4.65 while negative likelihood ratio was 0.15, and the diagnostic accuracy was 83.53%. Conclusions Serum PCT is a bacterial sensitive marker of bacterial infection in children, and the determination of the level of serum PCT is helpful for the diagnosis of bacterial infection, which can also be a basis for the use of antibiotics.

The clinical analysis of three methods in the treatment of intracranial bacterial infection

Objective To analyze the effect of three therapeutic methods to find an optimal approach to the treatment of intracranial bacterial infection by retrospectively reviewing 33 intracranial bacterial infection patients who were admitted from 1995 to 2008 in our hospital.Methods The treatments by intermittent lumbar puncture,continuous lumbar subarachnoid space drainage,and embedment of Ommaya cyst for continuous drainage from the ventricles were performed in 15 cases,12 cases,and 6 cases respectively along with intravenous application of full dose of antibiotics.Results Nineteen cases were cured and the best prognosis was from the group of Ommaya cyst embedment and continuous drainage from the ventricles.Conclusion Management goals are prompt recognition of the central nervous system(CNS)infection,rapid identification of causative organisms and initiation of treatment with the optimal management methods for complications.Embedment of Ommaya cyst for continuous drainage from the ventricle is a safe and effective treatment for intracranial bacterial infection.

Bacterial infections post-living-donor liver transplantation in Egyptian hepatitis C virus-cirrhotic patients: A singlecenter study

AIM To determine risk factors, causative organisms and antimicrobial resistance of bacterial infections following living-donor liver transplantation(LDLT) in cirrhotic patients.METHODS This prospective study included 45 patients with hepatitis C virus-related end-stage liver disease who underwent LDLT at Ain Shams Center for Organ Transplant, Cairo, Egypt from January 2014 to November 2015. Patients were followed-up for the first 3 mo after LDLT for detection of bacterial infections. All patients were examined for the possible risk factors suggestive of acquiring infection pre-, intra-and post-operatively. Positive cultures based on clinical suspicion and patterns of antimicrobial resistance were identified. RESULTS Thirty-three patients(73.3%) suffered from bacterial infections; 21 of them had a single infection episode, and 12 had repeated infection episodes. Bile was the most common site for both single and repeated episodes of infection(28.6% and 27.8%, respectively). The most common isolated organisms were gramnegative bacteria. Acinetobacter baumannii was the most common organism isolated from both single and repeated infection episodes(19% and 33.3%, respectively), followed by Escherichia coli for repeated infections(11.1%), and Pseudomonas aeruginosa for single infections(19%). Levofloxacin showed high sensitivity against repeated infection episodes(P = 0.03). Klebsiella, Acinetobacter and Pseudomonas were multi-drug resistant(MDR). Pre-transplant hepatocellular carcinoma(HCC) and duration of drain insertion(in days) were independent risk factors for the occurrence of repeated infection episodes(P = 0.024).CONCLUSION MDR gram-negative bacterial infections are common post-LDLT. Pre-transplant HCC and duration of drain insertion were independent risk factors for the occurrence of repeated infection episodes.

Diagnostic accuracy of C-reactive protein for bacterial infections in acute exacerbation of chronic obstructive pulmonary disease: A meta-analysis

Objective:The clinical diagnostic accuracy of C-reactive protein(CRP)for bacterial infections in acute exacerbation of chronic obstructive pulmonary disease(AECOPD)is still controversial.This study evaluated its accuracy through Meta-analysis.Methods:Studies on the diagnostic value of CRP for bacterial infections in AECOPD were searched form Web of Science,PubMed,Cochrane library,EMBASE,WANFANG DATA,CNKI and China Biology Medicine disc.The included studies were evaluated according to QUADAS-2 assessment tool.Stata 12.0 software was used for meta analyses to summarize the sensitivity and the specificity of the included studies,and the heterogeneity test was conducted.The symmetric receiver operating characteristic curves(SROC)was drawn and the area under the curve(AUC)was calculated,and the funnel plot was drawn to determine publication bias.Results:664 studies were initially identified,20 of which met the inclusion criteria(9 in English and 11 in Chinese).Meta-analysis results showed that the summary sensitivity and specificity of CRP in diagnosing bacterial infections in AECOPD were 0.84,95%CI(0.77-0.90)and 0.76,95%CI(0.67-0.82),respectively.The AUC of SROC was 0.87,95%CI(0.83-0.89).Conclusion:CRP has high accuracy,sensitivity and specificity in distinguishing AECOPD bacterial infections from non-bacterial infection.