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    30 December 2015, Volume 30 Issue 12
    Pay close attention to false positivity in the determinations of anti-HCV and anti-TP antibodies
    ZHU Qinghui.
    2015, 30(12):  1163-1166.  DOI: 10.3969/j.issn.1673-8640.2015.12.001
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    The false positivity in the determinations of anti-hepatitis C virus (HCV) antibody and anti-treponema pallidum (TP) antibody and the correspondence measures for solving this problem are presented. It is emphasized that the determinations of anti-HCV and anti-TP antibodies should use an antibody screening assay and a specific supplementary confirmation assay for the results showing repeatedly positive reaction in screening assay. Immunology test technicians in clinic and blood collection agencies should pay close attention to false positivity in the determinations of anti-HCV and anti-TP antibodies, which also is the purpose of this article.

    The study progress of false positivity in screening assay for detecting anti-HCV antibody and anti-TP antibody and its strategy
    CHEN Cuncun, FAN Lieying.
    2015, 30(12):  1167-1174.  DOI: 10.3969/j.issn.1673-8640.2015.12.002
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    There is a certain proportion of false positivity in screening assay for detecting anti-hepatitis C virus (HCV)antibody and anti-treponema pallidum(TP)antibody by enzyme-linked immunosorbent assay (ELISA) or chemiluminescence immunoassay (CLIA). Therefore, it is required to report positive results by confirmation assay . It is an alternative strategy for reducing false positive rate as far as possible in detecting anti-HCV antibody and anti-TP antibody by ELISA and CLIA and making the application of confirmation assay economic and rational by determining the signal-to-cut off (S/CO) ratio, when the positive predictive value of screening assay results reaches 95% with certain detection reagent (system) and in certain population.

    Analysis on repeatability and diagnostic threshold value of 2 ELISA systems for anti-HCV antibody determination
    MENG Cunren, TANG Jing, ZHANG Zhaoxia.
    2015, 30(12):  1175-1180.  DOI: 10.3969/j.issn.1673-8640.2015.12.003
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    Objective To analyze the repeatability and signal-to-cut off (S/CO) ratio of positive predictive value ≥95% in the determination of anti-hepatitis C virus (HCV) antibody by 2 enzyme-linked immunosorbent assay (ELISA) systems.Methods Recombinant immunoblot analysis (RIBA) was used to confirm anti-HCV antibody. Using Addcare ELISA 1100 automatic system (Addcare system) and TECAN+FAME combined system, by indirect ELISA, anti-HCV antibody was determined. High, medium and low concentrations of samples were collected. In 1 run of determination, the determination was repeated for 20 times(holes), and the precision of intra-analysis was calculated. For more than 10 d in a single (hole or pipe), 20 runs of determinations were performed, and inter-analysis precision was calculated .A total of 202 serum samples were collected, and receiver operating characteristic (ROC) curve was used to determine the optimal diagnostic threshold value[signal-to-cut off (S/CO) ratio]of 2 ELISA systems for the determination of anti-HCV antibody. The S/CO ratio scope of positive predictive value ≥95% of anti-HCV antibody determination of 2 ELISA systems was ide.pngied. Results The intra-analysis coefficients of variation (CV) were 5%, 8% and 10% for Addcare system and 3%, 7% and 8% for TECAN + FAME combined system, while the inter-analysis CV were 8%, 12%, 15% and 6%, 10%, 13%, respectively. The optimal diagnostic threshold values (S/CO ratios) of 2 ELISA systems were 3.20 and 2.90. The S/CO ratio scopes of positive predictive value ≥95% of anti-HCV antibody determination of 2 ELISA systems were≥2.41 and≥2.57. Conclusions The Addcare system and TECAN +FAME combined system have excellent repeatability and coincidence rate. The anti-HCV antibody determined by 2 ELISA systems has optimal S/CO ratio, and the S/CO ratio is correlated with confirmation assay positivity, so S/CO ratio can be used to predict anti-HCV antibody positivity. The optimal diagnostic threshold value and the S/CO ratio of positive predictive value≥95% are helpful for improving the results' reliability and reducing the sample numbers of confirmation assay.

    Investigation on the retesting procedure of anti-TP antibody determined by chemiluminescence microparticle immunoassay
    YANG Hua, YANG Xiaodong, RAO Lihua.
    2015, 30(12):  1181-1184.  DOI: 10.3969/j.issn.1673-8640.2015.12.004
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    Objective To investigate the retesting range of ani-treponema pallidum (TP) antibody determined by chemiluminescence microparticle immunoassay (CMIA) and improve the retesting procedure.Methods A total of 21 894 serum samples were screened by CMIA, the positive samples were retested duplicately by the same reagent kit of the same lot number and confirmed by western blotting (WB). The detection results were classifed into several groups for further analysis according to signal-to-cut off (S/CO) ratios. Results In 21 894 serum samples, 630 cases were positive by CMIA. The samples were classified into 7 groups according to S/CO ratios:1.0-2.0, 2.1-4.0, 4.1-6.0, 6.1-8.0, 8.1-9.0, 9.1-10.0 and>10.1. The retesting coincidence rates by CMIA were 62.5%(40/64), 80.0%(60/75), 93.9%(77/82), 100.0%(94/94), 100.0%(85/85), 100.0%(50/50)and 100.0%(180/180).The coincidence rates for retesting by WB and CMIA were 35.0%(14/40), 46.7%(28/60),75.3%(58/77), 81.9%(77/94), 88.2%(75/85), 96.0%(48/50) and 98.8%(178/180). Conclusions The S/CO ratio for retesting range by CMIA for the determination of anti-TP antibody is considered appropriate from 1.0-8.0 under a standardized laboratory condition and positive predictive value≥95% . Reports can be sent directly with S/CO ratio≥8.1. WB should be employed to confirmation assay with 1.0≤S/CO ratio ≤8.0. The appropriate retesting range not only can assure the accuracy of testing results, but also can reduce the sample numbers of confirmation assay.

    Study on the correlation between anti-TP antibody S/CO ratio by chemiluminescence immunoassay and positive results by confirmation assay
    XU Xiaofeng, JIANG Minglei, LU Renquan, ZOU Chunyuan, GONG Zhiyun, SHEN Li, GUO Lin
    2015, 30(12):  1185-1189.  DOI: 10.3969/j.issn.1673-8640.2015.12.005
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    Objective To investigate the correlation between anti-treponema pallidum(TP)antibody signal-to-cut off(S/CO)ratio by chemiluminescence immunoassay (CLIA) and positive results by confirmation assay.Methods A total of 208 anti-TP antibody positive samples (S/CO ratio≥1.0) were screened out by 2 CLIA systems, Abbott i2000 CLIA system (Abbott i2000)and Kemei Dongya Chemclin 600 CLIA system (Chemclin 600). The results were confirmed by western blotting (WB). Receiver operating characteristic(ROC)curve at optimal sensitivity and specificity was analyzed, and optimal S/CO threshold value was obtained by SPSS 19.0 software. The positive predictive value was calculated with every S/CO ratio interval, and the S/CO ratio of positive predictive value≥95%was obtained. Results By Abbott i2000 or Chemclin 600, 208 samples' S/CO ratio was determined.By WB, 35 cases of them were confirmed as negative, 128 cases were confirmed as positive, and 45 cases were indeterminate.The coincidence rates of WB compared with the 2 CLIA systems were 82.2% and 82.8%, respectively.When anti-TP antibody S/CO ratio of Abbott i2000 was ≥3.0, and anti-TP antibody S/CO ratio of Chemclin 600 was ≥4.0, the positive predictive value was ≥95%. Conclusions It is proposed that WB should be used if the S/CO ratio ranges are 1.0-3.0 determined by Abbott i2000 and 1.0-4.0 determined by Chemclin 600. If the S/CO ratio is above the upper limit, the samples can be reported as positive directly. It can not only reduce the confirmation assay sample number but also improve the reliability of determination report.

    Investigation on the positive cut off value of anti-TP antibody in pregnant women by chemiluminescence immunoassay
    CAI Xushan, QI Jiehua, CHEN Yu, WANG Dongjiang, WU Shoule.
    2015, 30(12):  1190-1192.  DOI: 10.3969/j.issn.1673-8640.2015.12.006
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    Objective To establish a reasonable positive cut off value of anti-treponema pallidum (TP) antibody in pregnant women by chemiluminescence immunoassay(CLIA).Methods A total of 13 974 serum samples from pregnant women for anti-TP antibody were collected. All the samples were determined by Kemei Dongya Chemclin CLIA system. The positive samples [signal-to-cut off (S/CO) ratio≥1.0] were further verified by western blotting (WB). The performance was evaluated by receiver operating characteristic (ROC) curve. Results The 152 samples of S/CO ratio≥1.0 were determined by Chemclin CLIA system. The screening positive reaction rate was 1.09%. The results verified by WB for the screening positive samples showed that 119 samples were positive, 7 samples were indeterminate,and 26 samples were negative. The false positive rate of screening positive reaction samples was 17.11% . The ROC curve indicated that the S/CO ratio for anti-TP antibody was 3.32 when Youden index reached maximum. The S/CO ratio was 3.25, when positive predictive value was ≥95% of Chemclin CLIA system. Conclusions In order to both reduce the false positive rate of anti-TP antibody screening and minimize the number of samples to be further determined by confirmation assay,each laboratory should set up a suitable S/CO ratio for different populations and determination systems (reagents) and determine the S/CO ratio scope to be further determined by confirmation assay.

    Investigation on the reference intervals of first morning urine ACR and urinary albumin concentration among adults in Tianjin
    CUI Xiaofan, LI Rong, WANG Huabin, LIU Rui, PAN Wenjie
    2015, 30(12):  1193-1197.  DOI: 10.3969/j.issn.1673-8640.2015.12.007
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    Objective To survey the reference intervals of urine albumin-creatinine ratio(ACR) and urinary albumin concentration in first morning urine samples from 20-60-year-old healthy subjects in Tianjin.Methods According to the inclusion criteria, 500 healthy subjects(20-60-year-old) were enrolled in this study. Their first morning urine samples were collected, and the concentration of urinary albumin (nephelometry immunoassay)and creatinine were determined, and urine ACR was calculated. According to the Clinical and Laboratory Standards Institute (CLSI) EP15-A and C28-A2, Z test was performed to analyze the data and was used to establish the reference intervals of urine ACR and urinary albumin concentration. Results There was no statistical significance among different ages in both male and female groups (P>0.05), and it was not necessary to establish the age-specific reference intervals for urine ACR and urinary albumin concentration. Males, on average, had higher urinary albumin concentration than females(P<0.05), and the sex-specific reference interval was needed. For urine ACR, there was no statistical significance with sex (P>0.05), and the uniform reference interval could be used in males and females. The distributions of urine ACR and urinary albumin concentration were skewed (P<0.05), so we used the 95th percentile(P95) as the reference interval. The urine ACR reference interval was 0-12.40 mg/g, and the urinary albumin reference intervals were 0-18.72 mg/L for male and 0-14.27 mg/L for females. Conclusions The urine ACR and urinary albumin concentration reference intervals among healthy subjects in Tianjin are lower than those recommended by clinical guidelines. There is no sex difference for ACR. However, it exists sex difference for urinary albumin concentration, and it needs different reference intervals for males and females.

    The correlation between serum levels of Hcy, blood lipid and cognitive disorder in patients with chronic schizophrenia
    WANG Xiaoyan, WANG Weiling, DING Binbin, CHEN Shurong, ZHANG Suqin, ZHU Guang, LUO Biming, WANG Zuowei
    2015, 30(12):  1198-1202.  DOI: 10.3969/j.issn.1673-8640.2015.12.008
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    Objective To determine serum homocysteine(Hcy)and blood lipid, and to investigate the relationships of Hcy and blood lipid with cognitive function in patients with chronic schizophrenia.Methods The levels of Hcy, total cholesterol(TC), triglyceride (TG), high-density lipoprotein cholesterol(HDL-C) and low-density lipoprotein cholesterol(LDL-C)were determined in 154 patients with chronic schizophrenia and 60 healthy subjects(healthy control group). The patients with chronic schizophrenia were classified into cognitive impairment group and non-cognitive impairment group according to the assessment of Montreal Cognitive Assessment (MoCA). The results were analyzed statistically. Results In cognitive impairment group, the levels of Hcy, TC, TG and LDL-C were significantly higher than those in non-cognitive impairment group and healthy control group(P<0.05), and the level of HDL-C was lower than that in healthy control group(P<0.05).Univariate Logistic regression analysis showed that Hcy,TC,TG and LDL-C were risk factors for cognitive impairment in patients with chronic schizophrenia [odds ratios(OR)were 1.114, 1.791, 2.141 and 1.556; 95% confidence intervals(CI)were 1.034-1.200, 1.237-2.593, 1.263-3.630 and 1.091-2.217]. Multivariate Logistic regression analysis showed that only Hcy was an independent risk factor for cognitive impairment in patients with chronic schizophrenia(OR=1.125, 95%CI was 1.040-1.217). Serum Hcy had negative correlation with MoCA score in patients with chronic schizophrenia(r=-0.362, P=0.000). Conclusions Cognitive impairment in patients with chronic schizophrenia may be associated with abnormal metabolism of Hcy and blood lipid.

    Investigation on the diagnosis significance of C reactive protein and adenosine deaminase in cerebrospinal fluid among children with meningitis
    XU Renrong, ZHANG Huihua, ZHU Huali
    2015, 30(12):  1203-1205.  DOI: 10.3969/j.issn.1673-8640.2015.12.009
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    Objective To determine C reactive protein and adenosine deaminase in cerebrospinal fluid, and to investigate the clinical diagnosis significance for tuberculosis meningitis, purulent meningitis and viral meningitis.Methods A total of 315 children with meningitis (102 cases of tuberculosis meningitis, 108 cases of purulent meningitis and 105 cases of viral meningitis) were enrolled, 96 children undergoing operation without meningitis were enrolled as control group, and their cerebrospinal fluid samples were collected. The levels of C reactive protein and adenosine deaminase were determined, and the results were compared. Results C reactive protein and adenosine deaminase in control and viral meningitis groups were significantly lower than those in tuberculosis and purulent meningitis groups (P < 0.05). Viral meningitis and control groups had no statistical significance (P>0.05). C reactive protein in purulent meningitis group was higher than that in tuberculosis meningitis group(P<0.05), and adenosine deaminase was lower than that in tuberculosis meningitis group (P < 0.05). C reactive protein in purulent meningitis group was positive, and the positive rate was 100%. There were 63 positive cases in tuberculosis meningitis group, and the positive rate was 61.76%. That in viral meningtis was negative. Conclusions In cerebrospinal fluid, C reactive protein and adenosine deaminase determinations have important reference significance for the differential diagnosis of bacterial meningitis (purulent meningitis and tuberculosis meningitis) and viral meningitis. Adenosine deaminase may be a good indicator for the diagnosis of tuberculosis meningitis,in order to provide the reference for the early diagnosis of various types of meningitis.

    Drug resistance analysis of Escherichia coli isolated from urinary tract infection in elder patients
    JIANG Lei, WU Fangfang, FU Chunming.
    2015, 30(12):  1206-1209.  DOI: 10.3969/j.issn.1673-8640.2015.12.010
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    Objective To analyze the drug resistance of Escherichia coli isolated from urinary tract infection in elder patients, in order to give a reference for the reasonable selection of antibiotics in clinical treatment.Methods From August 2011 to July 2014, a retrospective analysis was undergone regarding the drug resistance of Escherichia coli isolated from urinary tract infection in 837 elder inpatients (above 60 years old). A total of 17 kinds of antibiotics were determined singly or combinedly for their antimicrobial susceptibility. The drug resistance was analyzed according to the standard of the Clinical and Laboratory Standards Institute (CLSI) issued in 2010. WHONET 5.4 software was used in datum analysis. Results Escherichia coli was 100.0% sensitive to imipenem and meropenem. A significant sensitivity was observed for amikacin, amoxicillin-clavulanic acid and piperacillin-clavulanic acid (drug resistance rate<17.0%), whereas a considerable sensitivity was observed for cefoxitin and netilmicin (drug resistance rate was 30.0%). Less sensitivity was found for gentamicin, tobramycin, compound sulfamethoxazole, ticarcillin-clavulanic acid and the 2nd to 4th generations of cephalosporin antibiotics (drug resistance rate>49.0%). Penicillins, the 1st generation of cephalosporin and ciprofloxacin were almost inactive to Escherichia coli (drug resistance rate>83.0%). Extended-spectrum beta-lactamases (ESBLs)-producing isolates were found with increasing trend regarding 3 statistical years, but there was no statistical significance (P>0.05). Conclusions Escherichia coli displays different levels of drug resistance to different antibiotics. It may hold as a basis in the individual clinical treatment to patients.

    Analysis on the epidemiological characteristics of child respiratory virus infection in Songjiang, Shanghai
    HUANG Sheng, XU Wen, LI Li.
    2015, 30(12):  1210-1213.  DOI: 10.3969/j.issn.1673-8640.2015.12.011
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    Objective To analyze the epidemiologial characteristics of 7 common respiratory viruses, including influenza A virus, influenza B virus, respiratory syncytial virus, adenovirus and human parainfluenza virus type 1, type 2 and type 3, among children in Songjiang, Shanghai, and to provide the reference for clinical diagnosis and treatment, epidemic surveillance and prevention.Methods Nasopharyngeal swab samples were collected from 1 981 children presenting influenza-like symptoms in Songjiang, Shanghai, and were determined by direct fluorescent antibody staining(DFA) for the 7 common respiratory viruses. The positive rates were calculated and compared with different age groups and season groups. Results The positive rates of influenza A virus, influenza B virus, respiratory syncytial virus, adenovirus and human parainfluenza virus type 1, type 2 and type 3 were 4.3%, 2.8%, 11.0%, 0.4%, 1.5%, 0.1% and 3.2%, respectively. The positive rates of the 7 common respiratory viruses were most common in winter and spring (27.5% and 23.0%). There was statistical significance for the positive rates with different seasons (P<0.05). Except for human parainfluenza virus type 1 and type 2 and adenovirus, the positive rates of the remaining 4 respiratory viruses were statistically significant with different season groups (P<0.05). There was statistical significance in the positive rates of the 4 age groups (P<0.01), and the positive rates of the 7 common respiratory viruses were most common in 3-5-year-old group and 0-2-year-old group (27.7% and 24.8%). Conclusions Respiratory syncytial virus is the most common virus among children with influenza-like symptoms. Winter and spring are the epidemic seasons for the 7 common respiratory viruses in Songjiang, Shanghai. Children under 5-year-old are susceptible to these viruses.

    Research on the modification detection scheme for mycoplasma infection of genitourinary tract
    WU Lei, ZHOU Yunheng, CHEN Xiangming, WANG Guojiang, LIU Ying, CHEN Feng, FENG Jing, TANG Qunli, WANG Ruizhong, FANG Hua, ZHAO Hu, FANG Yi, ZHOU Chunmei, HUANG Shenglei, TANG Zhenhua, LU Tingyan, TANG Jin, WANG Jianqiang, HAN Lizhong, XIAO Shuzhen, HU Weizhong, YANG Yang, GU Weiming
    2015, 30(12):  1214-1218.  DOI: 10.3969/j.issn.1673-8640.2015.12.012
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    Objective To optimize culture methods and processes for mycoplasma and to establish a new scheme to improve the detection accuracy of ureaplasma urealyticum (Uu) and mycoplasma hominis (Mh) infections.Methods A practical standard laboratory procedure was established, and the models of mycoplasma culture in solid and liquid cultures were optimized. A total of 11 hospitals above Grade 2 in Shanghai participated in the study. Study cases were randomly selected, and genitourinary samples were determined. Statistical analysis was performed, and the clinical application of the procedure was evaluated. Results A total of 747 samples were collected. The overall positive rate was 45.1% (337/747), for Uu 41.1% (307/747) and for Mh 13.9% (104/747). The positive coincidence percentages of original sample inoculation were 92.6% and 94.0% (P<0.01), respectively. The positive coincidence percentages after transmission inoculation were 97.5% and 96.1% (P>0.05). The sensitivity of solid culture was improved when culture was transferred from liquid culture with color changes. A total of 17 liquid culture samples did not produce any colonies on the solid culture, and even the solid culture was passed twice. This indicated that solid culture decreased the false positivity in liquid culture. The determination time reduced significantly when solid and liquid cultures were performed simultaneously. Over 85% mycoplasma samples had colony formation within 24 h, and in 48 h liquid culture and solid culture had same positive percentage. Conclusions The combination of liquid culture and solid culture of mycoplasma produces high sensitivity and specificity, although the costs of the testing increase. This combination determination procedure should be recommended in the laboratory diagnosis of mycoplasma infections.

    Significance of Hcy, MPV, hs-CRP and FIB for the diagnosis of acute cerebral infarction
    ZHU Yuejin, ZHANG Hua, YAO Hongfeng.
    2015, 30(12):  1219-1221.  DOI: 10.3969/j.issn.1673-8640.2015.12.013
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    Objective To investigate the significance of homocysteine (Hcy), mean platelet volume (MPV), high-sensitivity C reactive protein (hs-CRP) and fibrinogen (FIB) in the diagnosis of acute cerebral infarction.Methods A total of 130 patients with acute cerebral infarction were enrolled. According to the degree of nerve defect, they were classified into mild group (37 cases), moderate group (62 cases) and severe group( 31 cases), and 70 healthy subjects were enrolled as control group. The correlations of each index between acute cerebral infarction group and control group were analyzed. Results Hcy, MPV, hs-CRP and FIB levels in acute cerebral infarction group were significantly higher than those in control group (P<0.05). Among mild, moderate and severe groups, Hcy, MPV, hs-CRP and FIB had statistical significance (P<0.05). The nerve defect degree was heavier, Hcy, MPV, hs-CRP and FIB levels were higher. Compared with 2 indices of Hcy, MPV, hs-CRP and FIB for each other, there was a significantly positive correlation (P<0.05). Conclusions Among patients with acute cerebral infarction, their Hcy, MPV, hs-CRP and FIB significantly increase, and are closely related the severity of disease. The determinations of Hcy, MPV, hs-CRP and FIB have important significance for the progress and prognosis.

    Methodological evaluation on stripping voltammetry for urinary iodine determination
    XU Zhong, SHENG Qingsong, ZHANG Tongjun, XIN Junwei
    2015, 30(12):  1226-1228.  DOI: 10.3969/j.issn.1673-8640.2015.12.015
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    Objective To evaluate the performance of stripping voltammetry for urinary iodine determination.Methods The trueness, precision, linear, cross-contamination and detection limit were analyzed by measuring human urinary freeze-dried powder and urine samples by stripping voltammetry using SR-I-100 microelement analyzer for urinary iodine, and the results were compared with those of arsenic cerium catalytic spectrophotometry. Results By stripping voltammetry, the biases of human urinary freeze-dried powders in low and high urinary iodine levels(104 μg/L and 486 μg/L)were -1.76% and 3.62%. The coefficients of variation (CV) for low, medium and high levels of urine samples (80.89 μg/L, 210.33 μg/L and 538.50 μg/L) were 9.81%, 4.27% and 3.64%. When the linear range was 100-540 μg/L, the equation of linear regression was Y=88.525X-6.678 0, R2=0.993 1.There was no cross-contamination.The lowest detection limit was 50μg/L. The CV was 12.85%. Between arsenic cerium catalytic spectrophotometry and stripping voltammetry, there was no statistical significance (P>0.05), and the correlation was good(R2= 0.97). Conclusions The stripping voltammetry has good trueness, precision, linear and detection limit without cross-contamination,and is suitable for clinical application.

    Determination of mercury in whole blood by inductively coupled plasma-mass spectrometry
    LIU Junxia, ZHOU Xin, YAN Chonghuai.
    2015, 30(12):  1229-1233.  DOI: 10.3969/j.issn.1673-8640.2015.12.016
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    Objective To study the feasibility of inductively coupled plasma-mass spectrometry (ICP-MS) for whole blood mercury determination.Methods Using hydrochloric acid as sample matrix, samples were digested with microwave digestion instrument, and ICP-MS was used to determine mercury in whole blood. The lowest detection limit,functional sensitivity, range, recovery, accuracy and precision of ICP-MS were evaluated. Results The detection limit of this method was 4.525×10-2 ng/mL, the functional sensitivity was 1.495 ng/mL, the analytical measurement range was 0.18-13.83 ng/mL, and the recovery rate was 92%-103%. The average values of low-level [(20±5) ng/mL ]and high-level [(50± 8)ng/mL] quality control materials for 20 d were 22.22 ng/mL and 51.39 ng/mL, and between-run precisions were 6% and 5%. Clinical random mixed whole blood, low and high whole blood quality control materials for 20 parts each were detected within 1 d, and the within-run precisions were 4.8%, 4.8% and 4.4%. Conclusions ICP-MS for the determination of whole blood mercury meets the clinical requirements.

    Automatic ELISA system for the detection of anti-mitochondrial M2 antibody and its clinical significance
    ZHANG Haiping, YAN Huiping, ZHANG Xin, ZHAO Dantong, MA Yinxue, SUN Limei, LI Zhuomin.
    2015, 30(12):  1234-1237.  DOI: 10.3969/j.issn.1673-8640.2015.12.017
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    Objective To detect anti-mitochondrial M2 antibody by automatic enzyme-linked immunosorbent assay(ELISA) system and to investigate its clinical significance.Methods A total of 267 serum samples[(112 samples from patients with primary biliary cirrhosis (PBC), 77 samples from patients infected with hepatitis B virus (HBV)and 78 samples from healthy controls] were detected for anti-mitochondrial M2 antibody by automatic ELISA system. The precision and the clinical significance of detecting anti-mitochondrial M2 antibody were evaluated. Results The precision was good .The within-run and inter-day coefficients of variation(CV) were <5%. The patients with PBC had positive rate 89.3% (100/112) for anti-mitochondrial M2 antibody, usually in high levels (>800RU/mL, 63%, 71/112). The positive rate of anti-mitochondrial M2 antibody was 5.2%(4/77)in patients with HBV infection, including 3 cases of 25-100 RU/mL and 1 case of >100 RU/mL, and it was 5.1%(4/78)in healthy subjects. Conclusions Automatic ELISA system for the detection of anti-mitochondrial M2 antibody guarantees the stability of results. It will provide valuable laboratory reference for the diagnosis of PBC and the differential diagnosis for other liver diseases.

    Drug resistance evaluation and gene analysis on the detection of inducible clindamycin resistance in Staphylococcus by 2 phenotype tests
    ZHANG Jinghua, YUAN Yinghua, LIU Yan, CHENG Jie, SUN Fenyong.
    2015, 30(12):  1238-1242.  DOI: 10.3969/j.issn.1673-8640.2015.12.018
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    Objective To evaluate the drug resistance performance and drug resistance gene on the detection of inducible clindamycin resistance in Staphylococcus by MicroScan Gram-positive composite plate(PC33 composite plate)and D test(erythromycin and clindamycin double-disk diffusion method).Methods The drug resistance of erythromycin/clindamycin composite well of the 115 isolates which were resistant to erythromycin and sensitive to clindamycin by MicroScan automatic ide.pngication was determined. Meanwhile, the inducible resistant phenotype of erythromycin to clindamycin was analyzed by D test, and the resistant gene to macrolide-lincosamide-streptogramin B (MLS) was detected by polymerase chain reaction(PCR). Results The detection rates of PC33 composite plate were 61.3% for Staphylococcus aureus and 47.6% for coagulase-negative Staphylococcus. The detection rates of D test were 61.3% for Staphylococcus aureus and 51.2% for coagulase-negative Staphylococcus. The difference between the 2 methods had no statistical significance(P>0.5). Using D test as a standard to evaluate PC33 composite plate resistant to inducible clidamycin resistance, the sensitivity was 95.1%, and the specificity was 100.0%. The predominant gene for constitutive MLB(cMLS) resistance to clindamycin was ermA. The predominant gene for inducible MLS(iMLS)resistance to clindamycin was ermC. Conclusions The detection results of inducible clindamycin resistance in Staphylococcus by MicroScan Gram-positive composite plate show a coincidence with D test. PC33 composite plate has good clinical significance. The detection of inducible clindamycin resistance should be paid attention in laboratories in order to guide physicians to select antimicrobial agents correctly.

    Application and evaluation of biochemical and immunological pipeline determination system
    LUO Chunhua, ZHAO Wu, XIAN Sheng, ZHANG Qingyong, HAN Gang
    2015, 30(12):  1243-1245.  DOI: 10.3969/j.issn.1673-8640.2015.12.019
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    Objective To improve clinical laboratory procedure management by biochemical and immunological pipeline determination system.Methods The use of pipeline determination mode replaced past traditional stand-alone mode. Results For more than 1 000 specimens/d, the pipeline determination mode had high efficiency-to-cost ratio. Compared with the traditional stand-alone mode, the advantage of pipeline determination mode can reduce the amount of bleeding from patients, reduce the number of pumping vessels, shorten samples' turn-around time (TAT), improve work efficiency, reduce the number of staff, reduce manual intervention, reduce error rate, reduce laboratory biological contamination, protect the health of operating staff and so on. Conclusions When treating specimens with excessive volume in clinical laboratories, pipeline determination mode has obvious advantages, which can significantly improve the efficiency of clinical laboratories.

    Review on external quality assessment of bacterial ide.pngication items in Shanghai for past 23 years
    CHEN Rong, XU Rong, LIU Xuejie, GE Ping.
    2015, 30(12):  1246-1249.  DOI: 10.3969/j.issn.1673-8640.2015.12.020
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    Objective To study the determination quality of microbiology external quality assessment (EQA) of bacterial ide.pngication items in Shanghai medical institutions for past 23 years.Methods Firstly, the EQA activity frequency, grouping, quality control material characteristic, transportation mode and returning way were analyzed. The results of microbiology bacterial ide.pngication items among participating laboratories in EQA of Shanghai Center for Clinical Laboratory (SCCL) from 1992 to 2014 were collected and analyzed statistically. The coincidence for the determinations of 14 major bacteria was analyzed statistically. Results EQA activity frequency reduced from 4 times per year to 2 times per year, and the number of samples increased from 3 samples per time to 5 samples per time. Subjects were not classified before, and now subjects did grouping. Before 2007, quality control materials were puncture-like semi-solid, after that, quality control materials were treated by freeze-drying technology as lyophilized form. Transportation modes were from taking by medical personnels themselves to cold chain system delivery in order to monitor whole process. Returning way was from paper to web uploading. The number of participating laboratories increased from 80 to 134 now, and the increasing rate was about 68%. The pass rate (score ≥80) and the excellent rate (score=100) increased year by year. The pass rate in 2014 was 100%, and the excellent rate in 2014 was 90%. The participating isolates were 23 genera with 105 kinds, and the coincidence rates of Staphylococcus, Enterococcus and Enterobacteriaceae ide.pngication were high, and many of them reached 100%. Conclusions The change of EQA activity mode makes it more equitable and standard for quality assessment. The microbiology bacterial ide.pngication quality increases year by year in Shanghai medical institutions, providing accurate results for clinic.

    Establishment of reference measurement procedures for serum electrolytes based on ion chromatography
    ZOU Bingde, ZOU Jihua, SHEN Min, ZHANG Man, WU Lishan, TU Minmin
    2015, 30(12):  1250-1256.  DOI: 10.3969/j.issn.1673-8640.2015.12.021
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    Ion chromatography as a new type of liquid chromatography for the analysis of anions and cations was developed in 1970. Recently, this analytical technology has become one of fastest developing methods in the field of analytical chemistry. It has been widely used in industrial, biological, medical, food, clinic and environmental samples due to its advantages of rapidness, simplicity,sensitivity and selectivity. This article summarizes the research on accuracy of ion chromatography technology as a reference measurement procedure for the determination of serum electrolytes, in order to provide valuable reference to make the analytical measurement results traceable in the field of clinical chemistry.

    Research progress of antiplatelet drug "nonresponder"
    CUI Chanjuan, QIAO Rui, ZHANG Jie.
    2015, 30(12):  1257-1262.  DOI: 10.3969/j.issn.1673-8640.2015.12.022
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    Despite the development of new antiplatelet agents,aspirin and clopidogrel dual antiplatelet therapy still has a major role in the prevention of stent thrombosis and ischemic events. However, a considerable number of patients in treatment with standard dual antiplatelet therapy continue to have cardiovascular events. This has been,in part,attributed to the fact that some patients may have poor antiplatelet effects. This phenomenon has caused considerable attention. Recently, a lot of researches on this phenomenon have appeared. However, these studies have some limitations, such as, the difference of platelet function tests, high inter-individual variability of antiplatelet agents and some other diseases affecting antiplatelet drug. In this review, we mainly discuss in vitro platelet function tests,genetic polymorphisms and some clinical disease interference with antiplatelet agents to elaborate the relationship between the reason of interference with antiplatelet agents and ischemic events.