Evaluation the performance of three HIV antigen-antibody combination assays in the detection of HIV in the window period / 中华检验医学杂志

Objective To evaluate the detectability of HIV antigen-antibody in the window period of acute infection by three HIV antigen-antibody assays.Methods Twenty-two samples of HIV seroconversion serum panels and thirty-seven HIV acute infected plasm samples from our laboratory collected from cohort study of men who have sex with men between 2009 and 2011,were assayed by ECLIA,CLIA and ELISA methods.All assays were evaluated for the ability to detect HIV in the window period,and the sensitivity of each assay for acute samples was analyzed.Chi square test was used for statistical analysis.Results The ability of detecting HIV in the window period of each assay was different.For HIV seroconversion serum panels,the results of ECLIA and CLIA assays were consistent,and the window period was shortened at least 1 to 5 days compared with ELISA assay.For HIV acute samples,all were HIV positive by ECLIA or CLIA assay,but for ELISA assay,94.6％ was positive.For samples before seroconversion,ECLIA and CLIA assay had the same sensitivity (93.5％),which is superior to ELISA assay (71.0％) (x2 =5.14,P ＜0.05).Conclusion The ability of detecting HIV in the window period was different for each assay.The results of ECLIA and CLIA assay are consistent,superior to ELISA assay.

A comparative study on the clinical performance of three fourth generation HIV diagnostic reagents / 中华检验医学杂志

Objective To compare the performance of fourth generation HIV antigen/antibody combined detection reagents for HIV early infection samples,international HIV seroconversion panel samples and routine clinical screening samples.Methods Thirty seven early HIV infected samples from the followup gays in Shen Yang between 2009 and 2011,66 seroconversion panel samples from BBI company (U.S.A),NABI company(U.S.A) and NIBSC company(U.K) and 703 routine HIV screening samples in the first hospital of China medical university in October 2010 were collected.All kinds of samples were tested by three diagnostic reagents based on chemiluminescence assay (CLIA),electrochemiluminescence assay (ECLIA) and enzyme-linked immunosorbent assay (ELISA) respectively.The detection sensitivity and specificity of these assays were analyzed.Results For 59 early infected and seroconversion samples,the sensitivities of both ECLIA and CLIA reagent were 96.61％ (95％ CI 91.5％-100.0％),higher than that of the ELISA kit (95％ CI 75.0％-92.9％) (x2 =5.341,P ＜ 0.05),which is 83.93％ ; Comparison among the three reagents for different subtypes of the antibody seroconversion samples showed that ECLIA had the highest sensitivity while CLIA was the lowest ; Detection sensitivity of the three reagents for the P24 antigen is CLIA ＞ ECLIA ＞ ELISA; With detection of 703 clinical routine screening samples,the specificities of three reagents were 100％ (CLIA),99.86％ (ECLIA) and 99.71％ (ELISA) respectively.Conclusions For the sensitivity of the fourth HIV diagnostic reagents CLIA and ECLIA are better than ELISA.The former two reagents are more suitable for identifying earlier HIV infection in clinic.

The comparison of the performance between third generation ELISA and fourth generation ELISA on acute and early HIV infection / 中华检验医学杂志

Objective To evaluate the performance of the third generation ELISA and the fourth generation ELISA for HIV-1 diagnosis assays on acute and early HIV-1 infected samples.Methods Sixtyseven acute/early HIV-1 infected samples were collected from the follow-up gays with seroconversion in Shen Yang city and from clinical patients in the First Affiliated Hospital of China Medical University with incomplete HIV-1 specific bands in western blot between 2008 and 2010.Third generation ELISA,fourth generation ELISA,western blot and HIV-1 viral load detecting were used for detecting these samples.The sensitivity,consistency were compared between third generation ELISA and fourth generation ELISA to detect the seroconversion samples and the window periods were abserved.Chi square test was used for statistical analysis.Results In the 67 acute/early HIV-1 infected samples,56 were HIV positive and 11 were HIV negative by the third generation ELISA.The sensitivity of the third generation ELISA was 83.6％ (95％ CI:72.5％ -91.5％); 63 were HIV positive,1 was at gray zone and 3 were HIV negative by the fourth generation ELISA.The sensitivity of the fourth generation ELISA was 94.0％ (95％ CI:85.4％ -98.3％),higher than the third generation ELISA(x2 =16.1,P ＜0.01).The consistency of the third generation ELISA and the fourth generation ELISA was 86.6％ ( 95％ CI:76.0％ - 93.7％).The earliest third generation ELISA positive sample was the sample collected 16 days after HIV infection and the earliest fourth generation ELISA positive sample was the sample collected 9 days after HIV infection.There was significantly different on the window periods between the third generation ELISA and the fourth generation ELLSA Conclusion The fourth generation ELISA had a higher sensitivity and shorter window period on acute/early HIV infected samples than the third generation ELISA,which is more suitable for the HIV early infection screening on high risk populations.

The clinical significance of urinary B-type natriuretic peptide assay for the diagnosis of chronic heart failure / 中华检验医学杂志

ObjectiveTo investigate the value of urinary BNP for diagnosis of chronic heart failure (CHF). MethodsThe levels of Urinary BNP and plasma BNP were measured by microparticle enzyme immunoassay (MEIA) in 83 patients with CHF and 30 control subjects. The heart function was classified according totheNYHAcriteria. Leftventricularejectionfractions(LVEF)weremeasuredby echocardiology. ResultsThe level of urinary BNP in patients with CHF was[90. 0(38. 3 -209. 5 )]ng/L and the level of plasma BNP was[680. 0 ( 289. 7 - 1543.5)]ng/L, both of them were much higher than those in healthy subjects,[17. 0 ( 13.0 - 33. 0)]ng/L and[84. 5 ( 56. 0 - 158.0 )]ng/L, respectively (P＜0. 01 ). The concentrations of urinary BNP increased gradually with more severe symptoms ( NYHA cl ass Ⅰ -ⅣV ). The level of urinary BNP was positively correlated with NYHA class ( r = 0. 742, P ＜ 0. 01 )and the level of plasma BNP (r =0. 842,P ＜0. 01 ) while negatively related with LVEF (r = -0. 801 ,P ＜0. 01 ). The level of urinary BNP in patients with LVEF ＜ 40％ was[143.0 ( 85. 0 - 258.0)]ng/L , which was much higher than that in patients with LVEF≥40％ ,[31.5( 17.3 -38. 8)]ng/L, (P ＜0. 01 ). At a decision threshold of 36. 5 ng/L, the urine BNP assay demonstrated a clinical sensitivity and specificity of 84％ and 80％ ,respectively. In this study,the area under the curve(AUC) was 0. 905. ConclusionUrinary BNP is a new candidate marker for the diagnosis of CHF,it provides a similar accuracy with plasma BNP.

Specific Serum Protein of Colorectal Cancer Detected by Surface-enhanced Laser Desorption/Ionization Time of Flight Mass Spectrometry / 中国医科大学学报

Objective To detect the specific serum protein of colorectal cancer by surface-enhanced laser desorption/ionization tune of flight mass spectrometry(SELDI-TOF-MS)and provide the foundation for early detection of colorectal cancer.Methods The levels of serum protein of 36 patients with colorectal cancer and 36 healthy control subjects were detected by weak cation exchanger protein chip(WCX2)chip and SELDI-TOF-MS.Results At the M/Z value range from 2 000 Da to 30 000 Da,82 protein peaks were found.The level of 3 604.240 Da protein was significantly higher in patients with colorectal cancer than in healthy control subjects,while the level of 12 861.368 Da protein was significantly higher in healthy control subjects than in patients with colorectal cancer(P＜0.05).The specificity,sensitivity,and positive predictive value of the detection of colorectal cancer using these 2 protien were 86.11%,77.78%,and 87.5%.respectively.Conclusion The 3 604.240 Da and 12 861.368 Da proteins can be used as the serum marker for early detection of colorectal cancer.

Drug Resistant Rate and Spectrum of Common Gram-negative Bacilli Isolated from Respiratory Tract of Patients:A Comparison Between ICU Ward and Non-ICU Ward / 中华医院感染学杂志

OBJECTIVE To learn the epidemiology of respiratory infection in ICU and non-ICU wards,and analyze the difference of drug resistance of Gram-negative bacilli between those two wards in order to provide the basis of empirical therapy for the respiratory infection from the different wards.METHODS The bacteria were identified by VITEK-2 and API system.Antibiotic sensitivity test adopted by K-B method.Data were analyzed by WHONET 5.3 software.RESULTS Totally 2184 strains of Gram-negative bacilli were isolated all from the respiratory tract,among which 655 strains were isolated from ICU ward and 1529 strains were from non-ICU ward.In ICU ward,the first five bacteria were Pseudomonas aeruginosa,Burkholderia cepacia,Acinetobacter baumannii,Chryseobacterium meningosepticum,and Stenotrophomonas maltophilia.It showed that non-fermentatives were the main pathogenic bacteria in ICU.In non-ICU ward,the first five bacteria were P.aeruginosa,Klebsiella pneumoniae,A.baumannii,B.cepacia,and S.maltophilia.Drug resistant rate of strain from ICU ward was generally higher than that from non-ICU ward,while levofloxacin in ICU ward showed the better activity than in non-ICU ward.CONCLUSIONS The respiratory infection is one of the hazards in nosocomial infection,drug resistant rate of Gram-negative bacilli from respiratory specimen in ICU is generally higher than that in non-ICU,and the main strains are the mlti-resistant non-fermentatives,which should attract the clinician′s more attention.

Antimicrobial Susceptibility and Distribution of Serratia in Hospital:Analysis of Result / 中华医院感染学杂志

OBJECTIVE To study clinical distribution of Serratia and learn the antimicrobial susceptibility to S.marcescens in vitro in order to offer the reference to optimally selecting antibiotic.METHODS It was analyzed that the 222 Serratia strains were distributed in and the was deteted 164 S.marcescens strains were isolated from our hospital from 2001 to 2006.Their VITEK-2 of French Bio-M?rieux Company was adopted to proceed the identification of bacteria and antimicrobial susceptibility test.Data were analyzed by WHONET 5.4.RESULTS Serratia were mainly isolated from sputum,urine,blood,secretion,bile,cerebrospinal fluid,abdominal fluid,et al.Infection of both in-and out-patients could be caused by Serratia and most were in surgery ward.S.marcescens had higher drug resistance rates to piperacillin,cefazolin,cefuroxime,gentamicin and tobramycin which were all above 60%.They were all susceptible to imipenem(minimum inhibitory concentration only 1 ?g/ml) and their susceptible rates to piperacillin/tazobactam,ceftazidime,cefepime,and levofloxacin were all higher than 80%.CONCLUSIONS Serratia are less isolated from clinics,but have much higher antimicrobial resistance to the 1st and 2nd generation cephalosporin and show diversely drug resistance to 3rd cephalosporin,so physicians should pay attention to the infection caused by them.

A Profile of Gram-negative Bacilli in ICU Ward During Eight Years:An Investigation / 中华医院感染学杂志

OBJECTIVE To learn the profile of Gram-negative bacilli in ICU ward during the eight years and analyze the drug resistant rates in order to provide the basis for empirical treatment of infection.METHODS The bacteria were identified by VITEK-2 and API system.Antibiotic sensitivity test adopted Kirby-Bauer method.Data were analyzed by WHONET5.4 software.RESULTS Totally 1492 strains of Gram-negative bacilli were isolated from ICU ward,which included 1146 strains of non-fermentaters,accounted for 76.8% and 346 strains of Enterobacteriaceae,accounted for 23.2%.The first five bacteria were Pseudomonas aeruginosa,Burkholderia cepacia,Acinetobacter baumannii,Stenotrophomonas maltophilia,and Escherichia coli by turns.The drug resistant rates were higher and had the tendency of increase by years.CONCLUSIONS Non-fermentaters are the main organisms in ICU ward.The species of bacteria are diversified and the drug resistant rates of them are serious,which should be monitored not only because helping clinical therapy but also discovering the prevalence of drug resistant strains.

Bacterial Spectra Investigation of Blood Culture and Clinical Analysis of Resistance of Pathogens / 中华医院感染学杂志

OBJECTIVE To offer the clinical physician the basis of optimal application of antibiotic,we have investigated the variation of antibiotic resistance and the bacterial spectra in the blood culture.METHODS Blood was cultured in BACTEC9120 of BD.The clinical isolates were identified by API and VITEK-2 of Bio-Merieux of France.Antibiotic susceptive test was done by Kirby-Bauer method and the result which was analyzed by WHONET5.3 and SPSS11.5 software was determined by the NCCLS standard of 2005′s edition.RESULTS Organisms were isolated from the blood specimen of 1468 patients,and there were 743 strains of Gram-positive cocci accounted for 50.7%,565 strains of Gram-negative bacilli accounted for 38.5%.Ninety three strains of fungi accounted for 6.3%.We analyzed the drug-susceptive result of Staphylococcus,Escherichia coli,and Klebsiella pneumoniae during five years,and found that all the antibacterial drug lost efficacy in some degree,except that the sensitivity of the staphylococci to vancomycin was 100%.CONCLUSIONS Gram-positive cocci are the main bacteria in blood culture,the species from which are diversified,and the rate of the drug resistance of some bacteria is high.It indicated that doctors should take more blood culture and monitor the bacteria drug resistant for the data of etiology,so that they can utilize antibiotic more reasonably.