Bacterial Infection Group Research Articles

Bacterial Co-infection in Hospitalized Children with Mycoplasma pneumoniae Pneumonia.

To describe the frequency and impact of bacterial co-infections in children hospitalized with Mycoplasma pneumoniae pneumonia. Retrospective, descriptive study. Tertiary-care hospital in Beijing, China. 8612 children admitted to Beijing Childrens Hospital from June 2006 to June 2014. According to the testing results of etiology we divided the cases into pure M. pneumoniae infection group and mixed bacterial infection group. We analyzed clinical features, hospital expenses and differences between these two groups. 173 (2%) of included children had bacterial coinfection. 56.2% of bacterial pathogens were identified as Streptococcus pneumoniae. The most common bacterium causing co-infection in children with M. pneumoniae pneumonia was S. pneumoniae.

Different pattern of viral infections and clinical outcomes in patient with acute exacerbation of chronic obstructive pulmonary disease and chronic obstructive pulmonary disease with pneumonia.

Respiratory viruses are well‐known causes of acute exacerbation of chronic obstructive pulmonary disease (AE‐COPD) and also important pathogens for concomitant pneumonia in COPD (CP‐COPD). However, the differences in a viral infection pattern and clinical impacts of respiratory viruses between the two groups have not been well investigated. The clinical and microbiological data from COPD patients admitted with AE‐COPD (n = 281) or CP‐COPD (n = 284) between January 2010 and December 2012 were reviewed. After excluding 88 patients (40 with AE‐COPD and 48 with CP‐COPD) who did not undergo a multiplex RT‐PCR test for respiratory viruses, the demographic characteristics, identified viruses, and clinical outcomes of the AE‐COPD and CP‐COPD groups were compared. Respiratory viruses were identified in 41.9% of AE‐COPD group and 33.5% of the CP‐COPD groups. The most common virus was influenza virus in the AE‐COPD group (33.7%) versus human coronavirus (24.1%) in the CP‐COPD group. Influenza virus was significantly more common in the AE‐ACOPD group than in the CP‐COPD group (P < 0.01). In‐hospital mortality of AE‐COPD and CP‐COPD were 1.2% and 12.3%, respectively (P < 0.01). Among CP‐COPD patients, in‐hospital mortality of patients with only viral infection group, only bacterial infection group, and viral‐bacterial co‐infection were 2.6%, 25.8%, and 17.5%, respectively (P = 0.01). Respiratory viruses were commonly identified in both AE‐COPD and CP‐COPD, influenza virus and human coronavirus were the most common viruses identified in AE‐COPD and CP‐COPD patients, respectively. The mortality rates of only viral infection group was significantly lower than only bacterial infection or viral‐bacterial co‐infection group in CP‐COPD patients. J. Med. Virol. 88:2092–2099, 2016. © 2016 Wiley Periodicals, Inc.

Inflammatory molecules expression pattern for identifying pathogen species in febrile patient serum.

Inflammatory molecules, such as cytokines and chemokines, have been considered markers for bacterial or viral infection in serum of patients in numerous studies. The aim of the present study was to investigate whether we were able to identify the pathogen species through patterns of inflammatory molecules. A total of 132 patients with elevated body temperature (tympanic temperature, >38.3°C) were recruited for this study. The concentrations of various inflammatory molecules in the patients' serum were evaluated using a cytometric bead array. Higher concentrations of interleukin (IL)-6 and IL-8 were detected in bacterial infection groups (patients with positive and negative blood cultures), as compared with the viral infection group. Viral infection (including influenza and dengue viral infections) was associated with higher concentrations of interferon-γ-inducible protein 10 (IP-10), as compared with the bacterial infection group. In addition, IL-8 levels in the gram-negative bacteria group were higher, as compared with the gram-positive bacteria group. However, IL-8 was insufficient for bacterial species identification. By contrast, dengue virus infection induced the highest serum level of IP-10 among all groups. In conclusion, detection of the patterns of inflammatory molecules may aid the subsequent management and treatment modalities in hospitals, although evaluation of these molecules alone may be insufficient for identifying the pathogen species.

Co-infection with EHEC and C. albicans in vitro enhances invasion and tissue damage of enterocytes induced by C. albicans

Objective To investigate, in vitro, the co-infection of Caco-2 cells (epithelial cells of intestinal mucosa) with Candida albicans and Enterohemorrhagic escherichia coli (EHEC). Methods The ability of both species to invade the Caco-2 cells was evaluated by inverted microscopy. Damage to Caco-2 cells was evaluated by measuring lactate dehydrogenase (LDH) activity. C. albicans virulence gene expression (ALS3, PLB1 and SAP4) was evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). Results Compared to simple infections with C.albicans alone, a co-infection invaded Caco-2 cells more rapidly, and C. albicans tended to proliferate more easily presenting in cluster shape of distribution. In addition, the LDH activity in the co-infection group (group 3) was the highest compared to groups 1, 2, 4 and 5, (F values of 14.48, 5.48, 11.74 and 3.45 respectively; all P <0.05); There was no significant difference in LDH activity found between the secondary fungous infection group (group 5) and the EHEC infection group (group 2) (F=2.03, P=0.54) or between the secondary bacterial infection group (group 4) and the Candida albicans infection group (group 1) (F=2.74, P=0.11). The LDH activities in groups 2 and 5 were significantly higher than that in groups 1 and 4 (all P <0.05). In addition, an up-regulation of toxicity-related genes (PLB1 and SAP4) were detected. The expression of PLB1 was higher in group 3 than that in group 1(P=0.014 3)and SAP4 was higher in groups 3 and 5 than that in group 1(P=0.027 2, P=0.001 8, respectively). Conclusions Using Caco-2 cells for an infection model, this study demonstrated that co-infecting in vitro enterocytes with C.albicans and EHEC enhanced the invasiveness and tissue damaging effects of C.albicans. Key words: Enterohemorrhage escherichia coli; Candida albicans; Co-infection; Invasion; Tissue damage; Inverted microscope; LDH; qRT-PCR

Predictive Factors of Spontaneous Bacterial Peritonitis Caused by Gram-Positive Bacteria in Patients With Cirrhosis.

Spontaneous bacterial peritonitis (SBP) in patients with cirrhosis is typically caused by gram-negative bacteria. However, the number of SBP cases due to gram-positive bacteria is steadily increasing. To date, little is known about the predictive factors involved in SBP infections.We performed a retrospective cohort study of patients (>18 years) with SBP due to gram-positive and -negative bacteria who were enrolled from January 2006 to December 2013 at Severance Hospital in Seoul, Korea where the incidences of hepatitis B virus associated chronic liver disease, cirrhosis, and hepatocellular carcinoma are high. Only the 1st SBP episode for each patient within the study period was included in our analysis.We identified 77 patients with cirrhosis and SBP. Of these, 27 patients (35%) had gram-positive bacterial infections and 50 patients (65%) had gram-negative bacterial infections. Our univariate analysis revealed that an early stage of cirrhosis (P = 0.004), lower creatinine level (P = 0.011), lower Sequential Organ Failure Assessment (SOFA) score (P = 0.001), lower Model for End-Stage Liver Disease score (P = 0.005), and use of systemic antibiotics within 30 days before SBP diagnosis (P = 0.03) were significantly associated with gram-positive bacterial infections. Our multivariate analysis indicated that the use of systemic antibiotics within 30 days before SBP diagnosis (odds ratio, 3.94; 95% CI, 1.11–13.96; P = 0.033) and a lower SOFA score (odds ratio, 0.56; 95% CI, 0.37–0.86; P = 0.007) were independent predictive factors of SBP caused by gram-positive bacterial infections in patients with cirrhosis. However, we did not observe a statistically significant difference in the 28-day mortality between the gram-positive and -negative bacterial infection groups (40.7% vs 46.0%, respectively; P = 0.407).In this study, the incidence rate of SBP caused by gram-positive bacteria in patients with cirrhosis was similar to the rates reported in recently published studies. Furthermore, the use of systemic antibiotics within 30 days before SBP diagnosis and a lower SOFA score were significantly associated with SBP caused by gram-positive bacteria in patients with cirrhosis.

Clinical values of the early detection of serum procalcitonin, C-reactive protein and white blood cells for neonates with infectious diseases.

Objective:To discuss application values of serum procalcitonin (PCT), C-reactive protein (CRP) and white blood cells (WBC) count in early diagnosis and treatment of neonatal bacterial infectious diseases.Methods:Clinical data of one hundred and thirty-six newborns with infectious diseases who were admitted into the hospital were retrospectively analyzed. They were divided into bacterial infection group (N=70) and non-bacterial infection group (N=66). Additionally, sixty-six healthy newborns who underwent physical examination in our hospital in the same period were selected as controls. Subjects in the three groups were all detected for serum PCT, CRP and WBC levels.Results:The levels of PCT, CRP and WBC in the bacterial infection group were much higher than those of the non-bacterial infection group and the healthy control group, and the differences had statistical significance (P<0.05). The positive rates of PCT, CRP and WBC of the bacterial infection group were higher than those of the non-bacterial infection group (P<0.05); the specificity and sensitivity of the PCT level were obviously higher than those of the CRP and WBC levels in diagnosing bacterial infectious diseases (P<0.05).Conclusion:Serum PCR, CRP and WBC levels are of high diagnostic values to neonatal infectious diseases. Compared to WBC and CRP, PCT is more sensitive index in the diagnosis of neonatal infectious diseases.

Procalcitonin as a biomarker of bacterial infection in pediatric patients after congenital heart surgery.

Background:Bacterial infection (BI) after congenital heart surgery (CHS) is associated with increased morbidity and is difficult to differentiate from systemic inflammatory response syndrome caused by cardiopulmonary bypass (CPB). Procalcitonin (PCT) has emerged as a reliable biomarker of BI in various populations.Aim:To determine the optimal PCT threshold to identify BI among children suspected of having infection following CPB.Setting and Design:Single-center retrospective observational study.Materials and Methods:Medical records of all the patients admitted between January 2013 and April 2015 were reviewed. Patients in the age range of 0-21 years of age who underwent CHS requiring CPB in whom PCT was drawn between postoperative days 0-8 due to suspicion of infection were included.Statistical Analysis:The Wilcoxon rank-sum test was used for nonparametric variables. The diagnostic performance of PCT was evaluated using a receiver operating characteristic (ROC) curve.Results:Ninety-eight patients were included. The median age was 2 months (25th and 75th interquartile of 0.1-7.5 months). Eleven patients were included in the BI group. The median PCT for the BI group (3.42 ng/mL, 25th and 75th interquartile of 2.34-5.67) was significantly higher than the median PCT for the noninfected group (0.8 ng/mL, 25th and 75th interquartile 0.38-3.39), P = 0.028. The PCT level that yielded the best compromise between the sensitivity (81.8%) and specificity (66.7%) was 2 ng/mL with an area under the ROC curve of 0.742.Conclusion:A PCT less than 2 ng/mL makes BI unlikely in children suspected of infection after CHS.

Role of cerebrospinal fluid procalcitonin in identification of intracranial bacterial infection and aseptic meningitis

Objective To investigate the role of the cerebrospinal fluid procalcitonin (PCT) in the identification of intracranial bacterial infection and aseptic meningitis in adults. Methods A total of 178 patients with the suspected symptom of intracranial bacterial infection at 48 to 72 h after neurosurgical brain tumor surgery at the Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University from October 2013 to March 2014 were analyzed retrospectively. The cerebrospinal fluid routine, biochemical and procalcitonin tests were performed. According to the diagnostic criteria of intracranial infection, they were divided into either a bacterial infection group (n=50) or an aseptic meningitis group (n=128). The cerebrospinal fluid PCT and its changes of the traditional cerebrospinal fluid detection index were compared. The receiver operating characteristic curve (ROC) was used to analyze the values of cerebrospinal fluid PCT for identifying the infection and aseptic meningitis. Results Compared with the aseptic meningitis group, the white blood cell count, polynuclear cell ratio, protein content, and PCT content were all increased in the cerebrospinal fluid of bacterial infection, and the blood glucose was reduced. There were significant differences (all P<0.01). There was no significant difference in chloride. The median (range) of cerebrospinal fluid PCT in the bacterial infection group was 0.15 ng/ml (0-3.09 ng/ml), and in the aseptic meningitis group was 0 ng/ml (0-0.46 ng/ml). The ROC results showed that the area under curve of the differential diagnosis of intracranial bacterial infection was 0.746. The diagnostic threshold was 0.075 ng/ml, the sensitivity was 68.0%, specificity was 72.7%, positive predictive value was 49.3%, and negative predictive value was 85.3%. The PCT in cerebrospinal fluid was positively correlated with the leukocyte, proportion of multinucleated cells, and protein (r=0.446, 0.453, and 0.482, respectively, all P<0.01). It was negatively correlated with glucose (r=-0.201, P=0.007). Conclusion The detection of PCT in cerebrospinal fluid has an important clinical application value for the diagnosis of intracranial bacterial infection after neurosurgical operation. Key words: Central nervous system bacterial infections; Meningitis, aseptic; Neurosurgical procedures; Procalcitonin; Cerebrospinal fluid

The utility of initial procalcitonin and procalcitonin clearance for prediction of bacterial infection and outcome in critically ill patients with autoimmune diseases: a prospective observational study.

BackgroundThe diagnostic value of procalcitonin (PCT) for patients with autoimmune diseases (AID) remains controversial and few studies focused on ICU patients. We sought to determine its diagnostic and prognostic values in this clowd.MethodsA prospective observational study was conducted in AID patients admitted to the ICU. Serum PCT levels were measured on ICU admission and subsequently at days 1, 3, 5 and 7, and peak PCT levels within 24 h (PCTpeak) were analyzed the utility for bacterial infection. The relationship of PCTpeak and SOFA score and severity of sepsis was performed correlation analysis. The change of PCT over time reflected as PCT clearance was compared to ICU 28-day mortality.ResultsOne hundred twelve patients were divided into bacterial infection group (group I, n = 54) and nonbacterial condition group (group II, n = 58). The median PCTpeak (range, μg/L) was higher in the group I than that in the group II (1.95 [0.38–37.56] vs. 0.64 [0.05–7.83], p = 0.002). PCTpeak had the best single predictor of bacterial infection (area under the curve [AUC], 0.902, p < 0.001) with a sensitivity of 79.6 % and a specificity of 89.6 % at the threshold of 0.94 μg/L. PCTpeak was also positive correlation with severity of sepsis (r = 0.731, p = 0.002), but its correlation with SOFA score was only found in subjects with bacterial infection (r = 0.798, p < 0.001). Importantly, the 5-day PCT clearance (PCTc-d5), rather than absolute PCT values, could earlier discriminate survivors (n = 73) from nonsurvivors (n = 39) (68.8 ± 9.8 vs. 21.8 ± 17.5 %, p < 0.001, respectively). PCTc-d5 < 50 % was an independent predictor of mortality (odds ratio 5.1, 95 % confidence interval 3.5 to 7.5; p = 0.001).ConclusionsIn critically ill patients with AID, elevated PCT levels are valuable for bacterial infection and are significantly positive correlation with the septic severity. Five-day PCT clearance may provide independent prognostic information. Larger, prospective trials are warranted to confirm the benefit.Electronic supplementary materialThe online version of this article (doi:10.1186/s12871-015-0122-9) contains supplementary material, which is available to authorized users.

Respiratory infectious phenotypes in acute exacerbation of COPD: an aid to length of stay and COPD Assessment Test.

PurposeTo investigate the respiratory infectious phenotypes and their impact on length of stay (LOS) and the COPD Assessment Test (CAT) Scale in acute exacerbation of COPD (AECOPD).Patients and methodsWe categorized 81 eligible patients into bacterial infection, viral infection, coinfection, and non-infectious groups. The respiratory virus examination was determined by a liquid bead array xTAG Respiratory Virus Panel in pharyngeal swabs, while bacterial infection was studied by conventional sputum culture. LOS and CAT as well as demographic information were recorded.ResultsViruses were detected in 38 subjects, bacteria in 17, and of these, seven had both. Influenza virus was the most frequently isolated virus, followed by enterovirus/rhinovirus, coronavirus, bocavirus, metapneumovirus, parainfluenza virus types 1, 2, 3, and 4, and respiratory syncytial virus. Bacteriologic analyses of sputum showed that Pseudomonas aeruginosa was the most common bacteria, followed by Acinetobacter baumannii, Klebsiella, Escherichia coli, and Streptococcus pneumoniae. The longest LOS and the highest CAT score were detected in coinfection group. CAT score was positively correlated with LOS.ConclusionRespiratory infection is a common causative agent of exacerbations in COPD. Respiratory coinfection is likely to be a determinant of more severe acute exacerbations with longer LOS. CAT score may be a predictor of longer LOS in AECOPD.

Soluble CD14 subtype (sCD14-ST) presepsin in premature and full term critically ill newborns with sepsis and SIRS

Neonatal sepsis still remains a major cause of morbidity and mortality in neonatal intensive care unit (NICU). Recently, soluble CD14 subtype (sDC14-ST) also named presepsin, was proposed as an effective biomarker for diagnosing, monitoring, and assessing the risk of neonatal sepsis and septic shock. The aim of this study was to investigate the diagnostic accuracy of sCD14-ST presepsin in diagnosing neonatal bacterial sepsis and in discriminating non-bacterial systemic inflammatory response syndrome (SIRS) from bacterial sepsis. This study involved 65 critically ill full-term and preterm newborns admitted to the neonatal intensive care unit (NICU), divided into three groups: 25 newborns with bacterial neonatal sepsis (group A); 15 newborns with a diagnosis of non-bacterial SIRS and with no localizing source of bacterial infection (group B); and 25 babies with no clinical or bacteriological signs of systemic or local infection receiving routine NICU care, most of them treated with phototherapy for neonatal jaundice (group C). A total of 102 whole blood samples were collected, 40 in group A, 30 in group B and 32 in group C. In 10 babies included in group A, sCD14-ST presepsin was also measured in an additional second blood sample collected 3days after the start of antibiotic treatment. sCD14-ST presepsin was measured by a commercially available chemiluminescent enzyme immunoassay (CLEIA) optimized on an automated immunoassay analyzer. Statistical analysis was performed by means of MedCalc® statistical package; receiver operating characteristic (ROC) analysis was computed, and the area under the ROC curve (AUC) was used to evaluate the ability of sCD14-ST to discriminate neonatal bacterial sepsis from non-bacterial SIRS. Blood sCD14-ST presepsin levels were found significantly higher in bacterial sepsis when compared with controls (p<0.0001); similarly, they were higher in non-bacterial SIRS when compared with controls (p<0.0001). However, no statistically significant difference was found between bacterial sepsis and non-bacterial SIRS (p=0.730). In our population, CRP and sCD14-ST did not correlate with each other. ROC analysis revealed that sCD14-ST presepsin has an area under the curve (AUC) of 0.995 (95% C.I.: 0.941–1.00) greater than that of CRP (0.827; 95% C.I.: 0.72–0.906). Similarly, in the group of babies with non-infectious SIRS, sCD14-ST AUC was greater than CRP AUC (0.979; 95% C.I.: 0.906–0.999 versus 0.771; 95% C.I.: 0.647–0.868). In controls, preliminary reference intervals for sCD14-ST ranged 223.4–599.7ng/L, being significantly different from those previously published elsewhere. In conclusion, sCD14-ST presepsin could be introduced in clinical practice as a diagnostic tool for improving the management of neonatal sepsis and non-bacterial SIRS.

Evaluation the clinical significance of procalcitonin levels detection on the diagnosis and treatment for elderly patients with severe pulmonary infection

Objective To evaluate the diagnostic and prognostic evaluation of Procalcitonin(PCT)levels detection for elderly patients with severe pulmonary infection. Methods 60 elderly patients with severe pulmonary infection were selected, as the infected group, wherein 45 cases with bacterial infection, 15 cases with non -bacterial infections. Another 60 cases elderly patients excluded infectious diseases were selected as the control group.PCT,CRP and WBC levels in two groups were detected and compared. The infection group was randomly divided into two groups,each of 30 cases, the control group received conventional anti-infection treatment, while the observation group developed solutions to optimize antimicrobial drugs by detecting changes in PCT and CRP.Antibiotic course, antimicrobial drug costs, superinfection and adverse reaction rates in two groups were recorded and compared. Results PCT,CRP levels and WBC in the infected group were(17.4±11.3)ng/mL,(43.5±18.7)mg/L and(10.4±7.3)×109/L,which in the control group were(0.4±0.2)ng/mL,(6.3±3.6)mg/L and(5.4±1.4)×109/L,the difference was statistically significance(t=7.369,9.570,3.295,all P<0.05).PCT levels of bacterial infection group was(27.2±14.7)ng/mL,which in non-bacterial infection group was(8.2±2.7)ng/m L,the difference was statistically significant(t=7.369,9.570,3.295,all P<0.05). Antibiotic course, antimicrobial drug costs, superinfection and adverse reactions in the observation group were significantly lower than those in the control group, the difference statistically significant(t=6.994,27.71,χ2=6.171, 6.984,all P<0.05). Conclusion PCT detection has an important value of infection diagnosis especially in elderly patients with severe pulmonary infection, and can be used as the basis for antibiotic treatment. Key words: Procalcitonin; C-reactive protein; Severe pulmonary infection; Antibiotic treatment

Early diagnostic value of combined inflammatory cytokines in bloodstream infection with different organisms

Objective To investigate the expression of procalcitonin (PCT) and C-reactive protein (CRP) , and endotoxin in bloodstream infection with different microorganisms, so as to assess the value of these inflammatory cytokines in early diagnosis of sepsis in bloodstream infections patients. Methods Data of 152 septic bloodstream infected patients with 90 male and 62 female aged from 62 to 102 years and 79.2±16.3 years in average admitted from January 2012 to December 2013 were analyzed retrospectively. According to the results of blood culture, the microorganisms could be categorized into gram-negative bacteria, gram-positive bacteria and fungus groups, and the levels of serum CRP, PCT, and endotoxin were compared among these groups of bloodstream infections patients within 24 hours after admission. Results (1) A total of 152 strains of microorganisms were surveyed including 92 gram-negative strains (61.18%) , 43 gram-positive strains (28.29%) , and 16 fungal strains (10.53%) . In the gram-negative strains, Klebsiella pneumoniae (n=29) , Acinetobacter baumannii (n=24) , Escherichia coli (n=23) , Burkholderia cepacia (n=9) and Pseudomonas aeruginosa (n=4) were the most common isolates. In the Gram-positive strains, 13 strains of Staphylococcus aureus were isolated. (2) In the gram-negative bacterial bloodstream infections group, there were 60 (64.52%) patients with endotoxin positive, and there were no endotoxin positive cases with detected gram-positive bacteria and fungal bloodstream infections. The median levels of PCT were significantly different among the three groups [gram-negative strains group: 7.760 (3.365, 28.585) ng/mL, gram-positive strains group: 0.705 (0.265, 3.225) ng/mL, fungal infection group: 1.245 (0.543, 1.998) ng/mL]. In the fungal bloodstream infection group, the mean level of CRP was higher than that in other two groups [gram-negative strains group: (126.01 ± 66.53) mg/L, gram-positive strains group: (77.58±54.21) mg/L, fungal infection group: (140.14±71.21) mg/L]. (3) The receiver operating characteristic (ROC) curve of inflammatory cytokines was made for the diagnostic value in bloodstream infections. ROC curve used to distinguish between gram-positive bacterial bloodstream infections group and fungal group showed that AUCPCT+ CRP=0.791. When PCT cut-off value was 0.92 ng/mL, and CRP cut-off value was 68.00 mg/L, the sensitivity was 50% and the specificity was 95.5%. ROC curve used to distinguish between the gram-negative bacterial bloodstream infections group and fungal group showed that AUCPCT+ CRP+ LPS=0.947. When PCT cut-off value was 2.16 ng/mL and CRP cut-off value was 94.10 mg/L, and endotoxin was positive, the sensitivity was 82.8% and the specificity was 100% . ROC curve used to distinguish between gram-negative bacterial bloodstream infections group and gram-positive bacterial group showed that AUCPCT+ CRP+ LPS=0.947. When PCT cut-off value was 2.68 ng/mL, CRP cut-off value was 106.5 mg/L, endotoxin was positive, the sensitivity was 74.2% and the specificity was 97.7% . Conclusions Gram-negative bacteria were the most common microorganisms in bloodstream infections in ICU patients. Compared with single inflammatory cytokine, the serum concentrations of PCT, CRP and endotoxin used together could provide more sensitivity and specificity for the early diagnosis of bloodstream infection with different microorganisms. Key words: Bloodstream infection; Sepsis; Gram-negative bacteria; Gram-positive bacteria; Fungal; Procalcitonin; C-reactive protein; Endotoxin

Evaluation of the immune function assay in pediatric living donor liver transplantation.

The immune function (ImmuKnow) assay is a measure of cell-mediated immunity based on the peripheral CD4+ T cell ATP activity. The efficacy of ImmuKnow in pediatric LDLT is not well documented. The aim of this study was to assess the correlations between the ImmuKnow and the clinical status in pediatric LDLT recipients. A total of 716 blood samples were obtained from 60 pediatric LDLT recipients (one month to 16 yr of age). The recipient's status was classified as follows: stable, infection, or rejection. The ImmuKnow values in the pediatric LDLT recipients with a clinically stable status had a lower immune response (IQR 85-297 ATP ng/mL) than that previously reported in adults. Meanwhile, the ImmuKnow values of the stable patients were not correlated with age. Furthermore, a significant difference was found in the ImmuKnow values between the bacterial or fungal infection and stable groups, but not between the CMV or EBV infection and stable groups. The ImmuKnow levels in the pediatric LDLT were lower than those observed in the adult LDLT. The proposed reference value is between 85 and 297 ATP ng/mL in pediatric LDLT recipients. We conclude that the ImmuKnow assay could be helpful for monitoring pediatric LDLT recipients with bacterial or fungal infections.

The evaluation of dot immunogold filtration method in detection of serum SAA and its clinical value of diagnosing the infectious diseases of children

Objective The purpose of this study was to assess the analysis capabilities of the dot immunogold filtration method on detecting serum amyloid A (SAA) protein in blood.It also aimed to research the clinical value of SAA in diagnosing the infectious diseases of children. Methods (1) The performance evaluation including the accuracy, within-run precision, inter assay variations, the linear and the distraction-analysis of SAA-SPOT was estimated following the EP file; From March to July in 2014, children from five 3A Grade hospitals in Guangdong Province were enrolled into this observational study.Data including white blood WBC count, CRP and SAA were obtained.(2) From March to July in 2014, children from five 3A Grade hospitals in Guangdong Province were enrolled randomly into this observational study.This study used a cross-sectional survey research method, and 386 children with bacterial infection and 219 children with virus infection were as the research object.The general, clinical diagnosis, treatment information as well as the data of blood SAA, C-reactive protein (CRP) and white blood cell (WBC) of children were collected.Data were analyzed by variance, independent t test, ROC curve analysis and stepwise regression statistics method. Results (1) The average recovery rate is 103.74 %.Coefficient of variation (CV) for 10 mg/L,100 mg/L within-run assays were 8.77%, 3.61% and between-run assays were 9.01%, 3.74%; the inter-day CV were 9.07%, 4.03% respectively; the linear range was 5 mg/L-200 mg/L, hemoglobin(5 g/L)，serum bilirubin(800 μmol/L)，triglyceride(TG, 22 mmol/L), and had no interference in SAA detection.When compared to the BNPRO quantitate system of SIEMENS, the coefficient of association of detection of SAA by SAA-SPOT was R2=0.96.(2) Compared with control group, the serum SAA of infection group (bacterial infection group,t=13.05，P=0.001；virus infection group t=7.68, P=0.001) and SAA/CRP ratio (bacterial infection group t=2.29, P=0.023; virus infection group t=3.32, P=0.01) were significantly increased.(3) The serum CRP and SAA rose similarly in bacterial infection, while in viral infection, only SAA increased significantly, CRP had no apparent change.In combination with CRP and WBC, SAA had the better diagnostic efficiency apparently. Conclusions As a POCT detection project, analysis capabilities of the SAA assayed by domestic SAA-SPOT can meet the requirements of clinical test.Combined with CRP, WBC and SAA can improve the efficiency in the diagnosing of infectious disease especially in the virus infection.As a new biomarker of infections, SAA is useful for the early auxiliary diagnosis and differential diagnosis of childhood infection. （Chin J Lab Med，2014,37：836-841） Key words: Infection; Serum amyloid A protein; C-Reactive protein; Gold colloid; Reagent kits, diagnostic

Evaluation of the effect of simultaneous infection with E. coli O2 and H9N2 influenza virus on inflammatory factors in broiler chickens

This study was conducted to evaluate the effect of experimental infection with &lt;em&gt;Escherichia&lt;/em&gt; coli O2 and H9N2 influenza virus on inflammato- ry factors in broiler &lt;em&gt;chickens&lt;/em&gt;. A total of 120 one-day-old Cobb broiler chicks were divided randomly to 6 groups. Inoculation program with 109 EID50/bird of the A/Chicken/Iran/772/1998 (H9N2) virus and 109 CFU/mL/bird of &lt;em&gt;E. coli&lt;/em&gt; O2 was carried out as follows: the chicks in group 1 were inoculated with virus and bacteria simultaneously on day 26, group 2 received virus on day 26 and then bacteria 3 days later, group 3 were inoculated with bacteria on day 23 and then virus on day 26, group 4 received only bacteria on day 26, group 5 were inoculated with only virus on day 26 and group 6 served as control. Serum samples were collected from wing vein at days 20, 30, and 40. Sera were examined for inflammatory mediators (TNF-a and INF-γ), acute phase reactants (haptoglobin and serum amyloid A) and gangliosides (total, lipid-bound and protein-bound sialic acids) using validated standard procedures. Among the measured parameters, serum gangliosides showed significant differences between the challenged and control groups in different days post inoculation (P&amp;lt;0.05). Significant increase in serum concentrations of serum sialic acids was observed on the 30th day in challenged groups. Elevations were found in the concentrations of serum gangliosides on day 40 compared to their first concentrations. The most obvious increase in serum sialic acids was observed in group 1 challenged with avian influenza virus and &lt;em&gt;E. coli&lt;/em&gt; O2 simultaneously. Bacterial infected group showed more significant changes in comparison with viral infected one. These findings suggest that serum sialic acids may be a useful indicator of H9N2 avian influenza virus and avian pathogenic &lt;em&gt;E. coli&lt;/em&gt; O2 co-infection.

The diagnostic value of different pro-inflammatory factor in early diagnosis of sepsis in patients with bloodstream infection

To investigate the expression of different inflammatory variables, such as procalcitonin (PCT), C-reactive protein (CRP), and endotoxin in septic patients with bacterial bloodstream infection, in order to assess the value of these variables in early diagnosis. The clinical data of 132 bacterial bloodstream infection patients with clinical diagnosis of sepsis in intensive care unit (ICU) of Beijing Shijitan Hospital of Capital Medical University from February 2012 to May 2013 were analyzed retrospectively. Patients were divided into Gram-negative (G(-)) bacterial bloodstream infection group (n=98) and Gram-positive (G(+)) bacterial bloodstream infection group (n=34) according to the result of blood culture. The inflammatory variables including white blood cell (WBC) count, percentage of neutrophils (N), CRP, PCT and level of endotoxin in blood of both groups within 6 hours of bloodstream infection were compared, and their correlation was analyzed. The receiver operating characteristic (ROC) curve of inflammatory variables for the diagnosis of bloodstream infection was plotted, and their diagnostic value for bloodstream infection was evaluated according to area under ROC curve (AUC), and finally the sensitivity and specificity of inflammatory variables for bloodstream infection were assessed based on the best diagnostic cut-off points. (1) The levels of the variables, including PCT, CRP, and endotoxin content in the G(-) bacterial bloodstream infection group were significantly higher than that of G(+) bacterial bloodstream infection group [PCT: 5.11 (0.99, 18.00) μg/L vs. 1.00 (0.36, 2.73) μg/L, Z=49.647, P=0.000; CRP: 111.5±57.4 mg/L vs. 75.9±56.6 mg/L, t=9.947, P=0.000; endotoxin: 18.00 (8.75, 28.00) ng/L vs. 5.00 (5.00, 6.25) ng/L, Z=52.333, P=0.000]. There was no significant difference in WBC and N between two groups. (2) The results of the correlation coefficient of the inflammatory variables showed: in G(-) bacterial bloodstream infection group positive correlation was found between PCT and CRP (r=0.671, P=0.000), PCT and endotoxin (r=0.916, P=0.000), CRP and endotoxin (r=0.687, P=0.004). On the other hand, in G(+) bacterial bloodstream infection group, correlation was shown between PCT and CRP (r=0.620, P=0.000), PCT and endotoxin (r=0.487, P=0.010), PCT and WBC (r=0.537, P=0.001), PCT and N (r=0.432, P=0.011), CRP and endotoxin (r=0.674, P=0.000), endotoxin and WBC (r=0.197, P=0.024). In all of bloodstream infection patients positive correlation was found between PCT and CRP (r=0.538, P=0.000), PCT and endotoxin (r=0.740, P=0.000), PCT and WBC (r=0.259, P=0.003), CRP and endotoxin (r=0.579, P=0.000), endotoxin and WBC (r=0.197, P=0.024). (3) The ROC curve in patients with the diagnosis of sepsis due to bloodstream infection showed that: in the G(-) bacterial bloodstream infection group, AUC for PCT was 0.825, sensitivity of 71.4% and specificity of 96.2% with the best cut-off value >2.455 μg/L; AUC for CRP was 0.761, sensitivity of 64.3% and specificity of 80.8% with the best cut-off value >79.45 mg/L; AUC for endotoxin was 0.797, sensitivity of 61.2% and specificity of 94.2% with the best cut-off value >15.5 ng/L. In the G(+) bacterial bloodstream infection group, AUC for PCT was 0.619, sensitivity of 41.2% and specificity of 82.7% with the best cut-off value >1.585 μg/L; AUC for CRP was 0.533, sensitivity of 32.4% and specificity of 82.7% with the best cut-off value >95.25 mg/L. The concentrations of PCT, CRP, and endotoxin in patients with G(-) bacterial bloodstream infection were significantly higher than those of G(+) bacterial bloodstream infection group. They are valuable for the early diagnosis of bloodstream infection, and judgment of its severity, and it is more valuable with the combination of PCT, CRP, and endotoxin concentration determinations.

Application of combined detection of sputum and serum procalcitonin in infants with community acquired pneumonia

Objective To evaluate the effects of combined detection of sputum and serum procalcitonin (PCT) to identify the etiology of community acquired pneumonia(CAP) in infants. Methods Retrospective analysis from August 2010 to September 2012 enrolled 435 patients with definitely etiological diagnosis of CAP.The all cases were divided into three groups according to the etiological diagnosis: 243 cases of bacterial infection group(including mixed bacterial infection), 106 cases of viral infection group, and 86 cases of mycoplasma infection group.Sputum and serum PCT levels in all cases were detected, with simultaneous detection of blood leukocytes, C-reactive protein levels. Results Sputum PCT level of bacterial infection group [(8.44±1.08) ng/ml] was significantly higher than viral infection group [(0.32±0.12) ng/ml] and mycoplasma infection group[(0.24±0.17) ng/ml], which showed statistically significant difference(F=765.03, P 0.05). The levels of blood leukocytes and C-reactive protein among 3 groups showed no statistically significant difference(P>0.05). As the critical value of the PCT>0.5ng/ml, the positive rates of sputum and serum PCT were significant difference in bacterial infection group (86.83% vs 73.66%, χ2=13.92, P<0.05). The sensitivity of diagnosing bacterial CAP by sputum and serum PCT levels were 86.83% and 73.66%, the specificity were 86.98% and 88.54%, respectively.The sensitivity and specificity of combined detection sputum and serum PCT were 72.02% and 94.27%. Conclusion Combined detection of sputum and serum PCT has clinical value and efficiency in pathogen identification of CAP. Key words: Procalcitonin; Community acquired pneumonia; Infants

The clinical value of serum procalcitonin in diagnosis and treatment for the patients with acute fever

Objective To investigate the clinical value of serum procalcitonin (PCT) in the diagnosis and treatment of the patients with high fever of acute illness.Methods A total of 285 febrile patients suffered from acute illness were divided into the conventional group (n =122) and the PCT group (n =163).The routine blood examination and serum level of C-reactive protein (CRP) detection were carried out for the dignosis of these febrile patiens of two groups,and in addition,serum PCT determination was carried out in the patients of PCT group.The diagnosis was comnfirmed by etiology or immunologic assays.Routine guidelines of administrating antibiotics were used for treatment in the conventional group.Whereas the antibiotic therapy given to patients of PCT group was guided by the serum PCT levels.Two groups were compared in respect of the antibiotics costs,duration of treatment with antibiotics,percentage of patients treated with antibiotics,efficiency of antibiotics treatment and the mortality rate.The patients of PCT group were further divided as per inflammatory markers of bacterial infection into three subgroups,namely bacterial infection group,viral infection group and non-infection group.At last,the relationship between serum PCT level and the prognosis of patients was analyzed.Results The cost of antibiotics,percentage of patients treated with antibiotics,and course of antibiotics treatment were (Y) (3586.5 ± 703.3),95.08％ and (15.01 ± 11.21) days,respectively in conventional group,whereas (Y) (1871.2 ± 433.5),54.60％,(11.22 ±7.10) days in PCT group with statistically significant difference between two groups (P ＜ 0.01),but there were no significant differences in clinical efficiency and mortality between groups (P ＞ 0.05).Serum PCT (1.12 ± 0.88) ng/ml in bacterial infection group was higher than that in both virus infected group (0.21 ± 0.1 1) ng/ml and non-infected group (0.18 ± 0.13) ng/ml.There was no statistics difference in serum PCT level between virus infected group and non-infected group (P ＞ 0.05).The diagnosis of bacterial infection with serum PCT was better than other inflammatory markers because serum PCT had high sensitivity,specificity,positive predictive value (PPV) and negative predictive value (NPV).Conclusions Serum PCT level was reliable to differentiate the nature of acute infection with high fever and to evaluate the prognosis by emergency physicians.There was an important significance for rational use of antibiotics by the guidance of PCT levels. Key words: Acute fever; procalcitonin ; Infections

CD15s is a potential biomarker of serious bacterial infection in infants admitted to hospital

Early recognition of serious bacterial infection (SBI) in children is essential for better treatment outcome. Flow cytometry analysis of neutrophil surface molecules has been more frequently utilized as a tool for diagnosis of infection. The infants (n = 105) under 6 months of age presenting to the pediatric emergency department with fever without apparent source who were hospitalized with suspicion of having SBI were enrolled in this prospective study. Sixty-nine infants were included into the training pool and were classified into bacterial or viral infection group. Validation pool consisted of 36 infants. The values of white blood cells counts, absolute neutrophil count (ANC), C-reactive protein (CRP), procalcitonin (PCT), neutrophil CD11b, CD15s and CD64 expression, and the percentage (%CD15s+) and absolute count (AC-CD15s+) of CD15s+ neutrophils were determined. In infants with SBI, %CD15s+ was 10.5 times more likely to be higher than the cut-off value. ANC, CRP, PCT, CD64, and AC-CD15s+ were also found as useful biomarkers for differentiation between bacterial and viral infection. The best fit multivariate logistic regression model included CRP, PCT, and %CD15s+ as strong predictors of SBI. The model's sensitivity (87 %) and specificity (83 %) indicated high model's accuracy. After validation on independent dataset, model's accuracy maintained high: 86 % sensitivity and 93 % specificity, confirming its reliability and supporting CRP, PCT, and %CD15s+ as real predictors. The findings of this study support assumption made in the literature on significance of CD15s in inflammation processes. Also, this study demonstrated for the first time that CD15s is potentially valuable biomarker of SBI in infants.