目的 了解2010—2019年北京协和医院肺炎支原体感染的实验室和临床特征,以及儿科患者使用不同药物进行治疗的转归.方法 回顾性收集2010年1月至2019年12月北京协和医院肺炎支原体感染患者的实验室和临床资料,分析不同季节、年龄、来源科室和疾病分布患者的肺炎支原体抗体阳性率,比较儿科住院患者大环内酯类、头孢菌素类、皮质类固醇类药和对症治疗等不同治疗方式的疗效和转归.结果 12985例患者中,15.0％(1950/12985)肺炎支原体抗体阳性;女性患者肺炎支原体抗体阳性率明显高于男性,差异有统计学意义(P<0.05).肺炎支原体感染高峰的季节为秋季.不同年龄段中,>5～10岁患者肺炎支原体抗体阳性率最高(P<0.05).与其他疾病患者相比,社区获得性肺炎患者肺炎支原体抗体阳性率最高(P<0.05).254例儿科肺炎支原体感染住院患者中,有176例、12例、7例和59例患者分别接受了大环内酯类、头孢菌素类、皮质类固醇类药和对症治疗.大环内酯类治疗组只有10例治疗效果不佳,其余均痊愈或改善,其他治疗方案均好转.结论 肺炎支原体感染在季节、年龄、患者科室和疾病分布等方面具有一定的特性,肺炎支原体感染实验室和临床大数据的回顾性分析具有重要意义,可为临床诊疗提供依据.

Objective: Hepatitis B virus (HBV) has a worldwide distribution and remains a leading public health problem in China. Method: Automated chemiluminescence microparticle immunoassay was used to test all five markers of HBV serology in serum samples among 696,048 patients, pregnant women, and normal subjects in Beijing from 2008 to 2018. Results: The overall prevalence of subjects categorized as previous/ occult HBV infection, inactive HBsAg carrier, active HBV infection, HBsAg, HBV susceptible, and immune via vaccination was 29.4%, 4.8%, 1.4%, 6.4%, 33.9% and 30.3%, respectively; men had a significantly higher prevalence of HBV infection than women. The prevalence of HBsAg was around 0.5% in subjects <= 10 years of age, increased dramatically to 3.7% in subjects between 11 and 20 years of age, reached the highest level of 7.9% in subjects between 41 and 50 years of age, and finally decreased to 2.8% in subjects >= 81 years of age. During the 10 years from 2008 to 2018, the prevalence of HBsAg was stabilized at about 6.0%, and indicators of HBV susceptibility, previous/ occult HBV infection, and immunity via vaccination were not further improved, despite the constant implementation of HBV vaccination since 1992. All four age groups (21 - 30y, 31 - 40y, 41 - 50y and 51 - 60y) of the normal adult population were found to have a significantly lower prevalence of HBsAg and HBV susceptibility but significantly higher prevalence of immunity via vaccination compared with corresponding age groups of the sub-total population. Conclusions: Although high coverage has been established among infants and young children, their vaccination alone could not reduce HBV infection in the adult Chinese population quickly. Adult populations with more vaccinated individuals are found to have fewer individuals with HBsAg. Vaccination in adults or at least in high-risk adults is an urgent need to decrease horizontal HBV transmission in China. (C) 2020 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-NDlicense (http://creativecommons.org/licenses/by-nc-nd/4.0/).

BackgroundPrimary cytomegalovirus (CMV) infection is prevalent worldwide and usually results in latency in immunocompetent populations. Reactivation of latent CMV can cause life-threatening complications in immunocompromised hosts.MethodsWe used the CMV Brite assay to test CMV antigenemia (pp65) in whole blood samples from 22,192 patients with or without autoimmune diseases in Beijing during 2008-2018.ResultsThe overall prevalence of CMV antigenemia was 19.5% (9.7%, males; 26.0%, females). The prevalence of CMV antigenemia was 35.1%, 58.6% and 11.4% in whole patients with autoimmune diseases, in patients with systemic lupus erythematosus (SLE) and in patients with non-SLE autoimmune diseases, respectively. All patients with non-autoimmune diseases, patients with HIV/AIDS or transplantation were found to have 5.0%, 27% or 14.8%, respectively. Patients≤20 years with SLE had a significantly higher prevalence of CMV antigenemia than did all SLE patients, on average. Patients>51 years with non-SLE autoimmune diseases had a significantly higher prevalence than did all patients with non-SLE autoimmune diseases, on average. The prevalence of CMV antigenemia in patients admitted to intensive-care units (ICUs) were 9.2%, which was significantly higher than that among all patients with non-autoimmune diseases. Patients with SLE had 23.8% of negative conversion of CMV antigenemia, significantly lower than the percentage of patients with non-SLE autoimmune (64.3%) and non-autoimmune (61.0%) diseases. The mean number of days to negative conversion of CMV antigenemia in patients with SLE was 35.3±35.8 days, which was significantly longer than that in patients with non-SLE autoimmune diseases (15.4±11.9 days) and non-autoimmune diseases (13.6±7.7 days).ConclusionsCMV antigenemia is found more likely in women than in men, more prevalently in patients with SLE than those with HIV/AIDS or transplant recipients, more frequently in patients admitted to ICUs. Patients with SLE had prolonged CMV antigenemia. The role of CMV appears important in SLE.

BACKGROUND:Epstein-Barr virus (EBV) is associated with nasopharyngeal carcinoma (NPC) which is prevalent in South China, and its association with systemic lupus erythematosus (SLE) or other autoimmune diseases has not been studied in the mainland of China. The EBV serological tests have been performed on patients with various diseases or manifestations for years at our institution and their values need to be evaluated.METHODS:For routine medical purposes, anti-EB viral capsid antigen (VCA) IgG, IgA and IgM antibodies, anti-EBV diffuse early antigen (EA-D) IgA antibodies, and anti-EBV nuclear antigen-1(EBNA-1) IgG antibodies were tested with commercial enzyme-linked immunosorbent assay (ELISA) in patients visiting Peking Union Medical College Hospital between 2013 and 2017. The test results were analyzed in this retrospective study.RESULTS:There were a total of 11122 serum samples available to be tested in the study. As indicators of past EBV infection, the prevalence of VCA-IgG/EBNA1-IgG were 66.6%/58.5%, 84.3%/78.8%, 92.9%/87.0% and 98.5%/95.4% in patients aged under 5 years, 6-10 years, 11-20 years and 21-30 years old, respectively, and these values maintained at this highest rate as age increased further. The prevalence of VCA-IgM, as a parameter of acute EBV infection, was 14.6%, 10.2%, 10.4%, 6.3% and 3.1% in patients aged under 5 years, 6-10 years,11-20 years, 21-30 years, 31-40 years old, respectively, and decreased to 2%~3% in older patients. Patients with elevated serum liver enzymes were more likely to have a higher prevalence of EA/D IgA antibody (P < 0.01) and young patients (≤30 years) with lymphadenopathy were more likely to have higher prevalence of VCA-IgM antibody (P < 0.01). The prevalence of VCA-IgA and EAD-IgA were 87.0% and 59.2% in NPC patients, respectively, and both were significantly higher (P < 0.001) than that in non-NPC patients. The prevalence of VCA-IgA was 45.4% and 25.6% in SLE patients and patients with other autoimmune diseases, respectively, which were significantly (P < 0.001) and mildly (P = 0.039) higher than their controls. In pediatric SLE patients between 6 and10 years old, the prevalence of VCA-IgG, VCA-IgA and EBNA1-IgG was 100%, 59.5% and 100%, respectively, all being significantly higher than the age (6-10y) related controls (P< 0.01). In the 705 cerebral spinal fluid (CSF) specimens, VCA-IgG, VCA-IgM, VCA-IgA and EAD-IgA were found to be positive in 12.1%, 0.15%, 0.25% and 0.25%, respectively. There were 157 paired specimens (CSF and serum were collected simultaneously) and VCA-IgG was identified as positive in 12.7% of the CSF and 100% of the serum specimens.CONCLUSIONS:Around 98% of Chinese patients were infected with EBV before 30 years of age and the highest rate of acute EBV infection were observed in patients under 5 years old. EBV infection was found to be associated with elevated serum liver enzymes, NPC and SLE. Acute anti-EBV antibody was valued for young patients with lymphadenopathy but limited value for CNS neuropathy.

目的 制备抗弓形虫特异性单克隆抗体并初步应用.方法 弓形虫RH株体外细胞培养增殖、纯化后灭活并超声波破碎免疫BALB/c小鼠,小鼠脾细胞与骨髓瘤细胞NS-1进行融合.酶免法筛查阳性杂交瘤并局限性稀释法进行克隆.免疫荧光、组化及印迹对筛选后的克隆进行鉴定,最终获得的杂交瘤制备腹水并使用Protein G进行纯化.结果 2只小杂交瘤融合后初步筛查出约80株阳性克隆.剔除与其它抗原有交叉反应、抗体效价低的克隆,最终获得抗弓形虫单抗杂交瘤1株,即14H4-1.免疫荧光和免疫组化显示该株单抗与弓形虫RH具有良好的反应性,免疫印迹试验显示与弓形虫28kDa抗原条带结合.14H4-1单抗免疫球蛋白亚型为IgG1,Protein G纯化腹水后的单抗效价≥1∶12800.14H4-1单抗已应用排除2例弓形虫感染疑似诊断.结论 制备的抗弓形虫单克隆抗体性能良好,可应用于弓形虫感染病原学检测.

Background Chlamydia pneumoniae (C. pneumoniae) is an obligate intracellular bacterium and a human pathogen that causes respiratory infectious diseases. More than 50% of the adult population worldwide was once infected with C. pneumoniae, but investigations into this topic are insufficient in mainland China. Methods Anti-C. pneumoniae IgG and IgM antibodies were detected using micro-immunofluorescence test in serum samples of patients visiting Peking Union Medical College Hospital between 2008 and 2017 for routine medical purposes, and the aim of this retrospective study was to analyze the test results. Results Among 12,050 serum specimens tested for anti-C. pneumoniae IgG and IgM antibodies, the overall prevalence of anti-C. pneumoniae IgG antibodies was 86.6%, 87.2% for men and 86.0% for women. Adult men (>20 years) were found to have a significantly higher prevalence of anti-C. pneumoniae IgG than women (χ2 = 30.32, P = 0.000). 3 to 5 years old patients were observed to have the lowest prevalence of anti-C. pneumoniae IgG, 42.8%, then increased with age, reaching the highest level of 98.6% in patients over 70 years of age. In the 10,434 specimens with C. pneumoniae IgG antibodies, the total geometric mean titer (GMT) for C. pneumoniae IgG was 45.71. Although GMTs were found to be significantly higher among all men than among all women (t = 5.916, P = 0.000), sex difference actually began in patients over 40 years of age and increased in the elderly. In the total 12,050 specimens, 1.2% had anti-C. pneumoniae IgM, 3.3% had anti-C. pneumoniae IgG with titers equal to or greater than 1:512; 0.39% had ≥4-fold increasing titers of antibodies in acute and convalescent phase paired samples, and 4.4% were finally confirmed to have acute antibodies against C. pneumoniae. 6 to 10 years old patients were found to have the highest rate of both IgM antibodies (3.9%) and acute antibodies (6.2%) against C. pneumoniae. Acute antibodies against C. pneumoniae were found to be more frequent in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD, 14.0%, χ2 = 20.43, P = 0.000), patients with pneumonia (7.8%, χ2 = 51.87, P = 0.000) and patients with acute respiratory tract infection (12.3%, χ2 = 60.91, P = 0.000) than among all patients (4.4%). Both anti-C. pneumoniae IgG and IgM antibodies should be tested for acute antibodies against C. pneumoniae as testing for either alone will underestimate by a maximum of two-thirds the incidence of acute antibodies against C. pneumoniae. Conclusions More than 86% of Chinese patients on an average were once infected with C. pneumoniae. Adult men had both a higher prevalence and higher levels of antibodies than women. 6 to10 year old patients were found to have the most frequent acute infection of C. pneumoniae. C. pneumoniae is associated with AECOPD, pneumonia and acute respiratory tract infection. Anti-C. pneumoniae IgG and IgM should be tested simultaneously to avoid underestimation of acute antibodies against C. pneumoniae.

Objective To prepare monoclonal antibody against early and late antigens of cytomegalovirus (CMV) and to use the antibody for the identification of isolates from proficiency testing and clinical samples.Methods BALB/C mice were immunized with soluble and formaldehyde to inactivate CMV antigens from the CMV-infected MRC-5 cells at 24,48 and 72 hours after inoculation.Mouse myeloma NS-1 cells were fused with spleen cells of the immunized mice.Positive hybridomas were screened with EIA and were cloned with limited dilution method.The immunofluorescent and immunoblotting tests were applied to confirm the positive clones after screening.The ascites was prepared with the identified hybridoma and was purified by Protein G.The purified monoclonal antibody was used to identify CMV isolates from CAP proficiency testing samples and clinical samples.Results A total of 110 positive hybridomas clones were preliminary identified from fused cells of three immunized mice.One hybridoma clone,23B5-1 was finally obtained while other clones were eliminated due to cross-reactive with other antigens,low antibody titers or without reactions with both CMV early and late antigens.It was shown that 23B5-1 reacted with CMV infected MRC-5 cells from 3 hours to 120 hours (5 days) after inoculation.All of immediate-early,early and the late CMV antigens were recognized by the monoclonal antibodies simultaneously.It was also shown that 23B5-1 reacted with five CMV protein bands between 25KD to 50 KD in western blot.The immunoglobulin subclass of antibody was IgG1 and the titer of the purified antibody was equal or more than 1:12 800.The results of staining with the antibody were consistence with predicted results for all six CMV isolates from proficiency testing and ten isolates from clinical samples.Conclusions The performance of our self-prepared monoclonal antibody was good according to the preliminary application.

Objective To retrospectively study the serum IgG and IgM antibodies against toxoplasma, rubella virus, cytomegalovirus and herpes simplex virus type 1&2 in various populations, and analyze the clinical values.Methods From 2008 to 2015, 2 661 pregnant women, 324 infertile women, 2 492 women with abnormal pregnancy history, 623 women with recent abnormal pregnancy, 261 infants with intrauterine growth retardation and other diseases, 170 women for preconceptual examination, and 702 women for physical examination in Beijing were included .Commercial EIA kits were used to detect serum IgG and IgM antibodies to toxoplasma, rubella virus, cytomegalovirus and herpes simplex virus type 1&2. Positive reactions of IgM antibodies to any pathogens were re-tested with another kind of commercial EIA kit. PEMS3.1 software was used for statistical analysis.Results The prevalence of serum IgG or IgM antibodies against toxoplasma, rubella virus, cytomegalovirus and herpes simplex virus type 1& 2 were found within 0.7%-1.6%(0-1.2%) , 85.3%-92.0% ( 0.4%-2.7%) , 89.1%-94.9% ( 0.7%-1.7%) , 74.8%-86.0% ( 0 -0.7%) , 8.1% -17.4% ( 0 -4.1%) respectively in the studied population groups.The prevalence of TORCH IgG and IgM antibodies were not found to be higher in both populations with past suspicious exposure ( infertile women and women with abnormal pregnancy history ) and recent suspicious exposure ( women with recent abnormal pregnancy and infants with intrauterine growth retardation and other diseases) than that in pregnant women and women for preconceptual and physical examination. Conclusion No associations between TORCH infections and the suspicious exposure were found in the populations above.

目的 通过分析梅毒螺旋体血清学比对试验,探讨增强化学发光技术(enhanced chemiluminescence technologies,ECT)在急诊化验室筛查流程.方法 增强化学发光技术与梅毒螺旋体颗粒凝集试验(TP-PA)法同时检测2013年4月～2014年5月间257例患者血清标本梅毒螺旋体抗体,二者不相符的检测结果,使用梅毒快速血浆反应素环状卡片试验(RPR)和荧光螺旋体抗体吸收试验(FTA-ABS)进行验证.结果 ECT与TP-PA比对敏感度为98.9％,特异度为88％,二者具有较高的一致性(K=0.921,P＜0.05);二者结果不符标本11例(4.28％),ECT阳性TP-PA阴性的不符标本9例中,FTA-ABS IgG抗体9例均为阴性,RPR检测阳性1例;ECT阴性TP-PA阳性的不符标本2例,RPR检测与FTA-ABSIgG抗体均为阴性.经FTA-ABS验证后的ECT敏感度为100％,特异度为88.3％.结论 ECT敏感度高,特异度较好,且简便快速的方法学适用于急诊化验室梅毒血清学试验筛查.ECT阳性时,建议使用RPR检测以确定疾病的活动性.

Background The hepatitis B, hepatitis C, human immunodeficiency viruses and Treponema pallidum are important causes of infectious diseases concern to public health. Methods Between 2010 and 2014, we used an automated chemiluminescence microparticle immunoassay to detect the hepatitis B, hepatitis C, and human immunodeficiency viruses as well as Treponema pallidum (the rapid plasma regain test was used in 2010–2011). Positive human immunodeficiency virus tests were confirmed via western blotting. Results Among 416,130 subjects, the seroprevalences for hepatitis B virus, hepatitis C virus, human immunodeficiency virus, and Treponema pallidum were 5.72%, 1.23%, 0.196%, and 0.76%, respectively. Among 671 patients with positive human immunodeficiency virus results, 392 cases were confirmed via western blotting. Hepatitis B and human immunodeficiency virus infections were more frequent in men (7.78% and 0.26%, respectively) than in women (4.45% and 0.021%, respectively). The hepatitis B and C virus seroprevalences decreased from 6.21% and 1.58%, respectively, in 2010, to 5.37% and 0.988%, respectively, in 2014. The human immunodeficiency virus seroprevalence increased from 0.04% in 2010 to 0.17% in 2014, and was elevated in the Infectious Disease (2.65%), Emergency (1.71%), and Dermatology and Sexually Transmitted Diseases (1.12%) departments. The specificity of the human immunodeficiency virus screening was 71.4%. The false positive rates for the Treponema pallidum screening tests increased in patients who were 60–70 years old. The co-infection rates for the hepatitis C and human immunodeficiency viruses were 0.47% in hepatitis C virus-positive patients and 7.33% in human immunodeficiency virus-positive patients. Conclusions During 2010–2014, hepatitis B virus and human immunodeficiency virus infections were more frequent among men at our institution. Although the seroprevalences of hepatitis B and C viruses decreased, the seroprevalence of human immunodeficiency virus infection increased (with higher seroprevalences in high-risk departments). Older patients were more likely to exhibit false positive findings for syphilis.

Objective To prepare monoclonal antibodies(McAbs)against the CMV pp65 antigen,and establish immumofluorescence method for detection of CMV antigenemia in peripheral blood leukocytes.Methods 24,48,72 hafter CMV AD169 infected human embryonic lung fibroblast(MRC-5),CMV antigen was prepared through ultrasonic fragmentation and formalin inactivation,BALB/C mice were immunonized by the CMV pp65 antigens,and the standard method was used to produce monoclonal antibodies against the CMV pp65 antigen.The prepared monoclonal antibodies were used to establish immumofluorescence method for detection of CMV antigenemia in peripheral blood leukocytes,and the established method was compared to CMV BriteTMkit.Results There was two hybridoma cells producing specific monoclonal antibodies,and named 13D1-3and 29F1-1,respectively.The immunoglobulin subtypes were IgG1 and IgG2a.After purification,monoclonal antibodies of ascites fluid also had good immunological characteristics.Compared monoclonal antibody 13D1-3 with CMV BriteTM kit,the positive coincidence rate was88.8%,negative coincidence rate was 98.9% and the total coincidence rate was 97.3%(kappa=0.895),predicted high consistency.Conclusion This study might have successfully produced monoclonal antibodies against the CMV pp65 antigen and established immumofluorescence method for detection of CMV antigenemia in peripheral blood leukocytes,which could indicate high consistency compared with CMV BriteTMkit.

OBJECTIVE:To detect serum Chlamydia pneumoniae (C.pneumonia) antibodies and analyze the epidemiologic data.METHODS:Micro-immunofluorescence (MIF) was used to detect IgG and IgM antibodies against C.pneumoniae in 7 802 serum specimens from May 2008 to September 2013. C.pneumoniae past or recent infections were determined based on specific IgG and IgM antibodies and their titers. The analysis of relationship between age, gender and other clinical factors associated with antibody titers was performed.RESULTS:The positive rate of C.pneumonia IgG antibodies ( ≥ 1: 16 and <1: 512) was 87.5% (6 827/7 802). And the lowest rate of 50.6% (78/154) was shown in patients of 2-4 years age group while the highest rate of 98.7% (1 277/1 294) in those above 70 years old. The average geometric mean titer (GMT) of C.pneumonia IgG antibodies was 43.9. GMT in males was significantly higher than that in females (45.8 vs 41.9, P = 0.000 1). And 282 (3.6%) patients were diagnosed with recent C.pneumoniae infection (IgG ≥ 1: 512 or IgM ≥ 1: 16 or acute and convalescent serum antibody titers turned to positive or four times and more elevated). The lowest rate of 0.5% (2/417) was detected in < 2-year-old patients while the highest rate of 6.7% (24/357) in 10-14-year-old group patients. The miss ratio was as high as 68.1% (192/282) if C.pneumoniae IgM antibody was used as an only criteria for C. pneumoniae recent infection. The recent infection rates in patients with autoimmune diseases (7.1% (24/336) ) and those with pneumonia/chest radiological shadow findings (4.7% (69/1 467)) were statistically higher than the average rate (3.6%) of total population (P = 0.000 4, 0.014 0).CONCLUSIONS:The positive rate of C.pneumonia IgG antibody is quite high in the population. And the GMT of C.pneumoniae IgG antibody in males is significantly high than that in females. Recent C.pneumonia infection is to be missed if IgM antibody is used as a sole criterion.

Objective To assess the efficacy of the two antiviral medications in preventing cytomegalovirus infection and cytomegalovirus disease in renal transplant recipients.Method We searched articles from Pubmed,EMbase,Cochrane Library,Wanfang Med Online,and China's biomedical journal citation database on line.Randomized controlled trials evaluating preemptive treatment and universal prophylaxis for cytomegalovirus infection and cytomegalovirus disease in renal transplant recipients were reviewed.Two reviewers screened studies and assessed study quality according to the study population,intervention measure and results.Finally data from included studies were subjected to meta-analysis.Result Six studies involving total 752 renal transplant recipients were included in this review.Compared with preemptive treatment,universal prophylaxis significantly reduced the risk of cytomegalovirus infection at 3 rd and 12 th month,and the risk of cytomegalovirus disease at 12 th month after transplantation (RR =12.13,95 ％ CI.6.59～22.36,P＜0.05; RR =2.21,95％CI:1.62～3.01,P＜0.05; RR=1.79,95％Chl.22～2.63,P＜0.05).There was no statistically significant difference in the incidence of other opportunistic infection and acute rejection.Conclusion Universal prophylaxis was more effective than preemptive treatment in preventing CMV infection and CMV disease in renal transplant recipients.

传统病毒细胞培养及鉴定技术因为花费大、操作繁琐、周期长且实验室技术要求高,一般临床实验室较少开展.但是,病毒培养技术仍然是临床实验室高水平的标志,其结果许多情况下仍被视为"金标准"[1].病毒培养特异度是100％,虽然敏感度低于100％,但2009年的甲型流感病毒大流行,病毒培养敏感度远高于POCT等免疫学方法[2].现将2008至2011年美国病理学家学会(College of American Pathologists,CAP)病毒培养室间质评项目及笔者参加质评结果报告如下.

OBJECTIVE:To retrospectively analyze the cytomegalovirus (CMV) antigenemia test and re-test after antiviral chemotherapy in patients with autoimmune and non-autoimmune diseases.METHODS:CMV Brite kit and indirect immunofluorescence were used to detect CMVpp65 antigenemia in 6471 peripheral blood leukocyte specimens from 5325 clinic and hospitalized patients with clinically suspicious CMV infections from May 2008 to February 2012. And the positive results were defined as episodes of systemic CMV activity.RESULTS:In 6471 EDTA-treated peripheral blood specimens, 948 (14.6%) were found with positive CMV antigenemia. The average positive rate from 13 kinds of autoimmune diseases was 34.9% (670/1922) in which systemic lupus erythematosus patients had the highest (52.4%, 551/1052). Meanwhile, the average positive rate from 12 kinds of non-autoimmune diseases was only 6.1% (144/2367) in which it was 17.3% (27/156) in patients with respiratory/acute renal failure, acquired immunodeficiency syndrome (AIDS) and kidney transplant recipients. And 189 patients with positive antigenemia were re-tested after antiviral chemotherapy and only 64 (33.9%) were converted negatively.CONCLUSIONS:Patients with autoimmune diseases have replaced traditionally immunocompromised patients, e.g. AIDS and kidney transplant recipient, to become the highest risk group of systemic CMV activity. Negative conversion rate of CMV antigenemia is low after antiviral chemotherapy.

Objective To define the boundary values of the S/CO (signal-to-cut-off) for screening hepatitis C antibody (anti-HCV) 95% true-positive samples by automatic chemiluminescence assay in Chinese population. Methods 202 anti-HCV-positive samples was screened out with automatic chemiluminescence instruments. S/CO values between 1-20 in the I7000 or 1-35 in the ECI were set as criteria in the study group. Anti-HCV serological results were confirmed by chiron recombinant immunoblot assay( RIBA ) and HCV 3.0 strip immunoblot assay (SIA). HCV RNA was tested. Receiver operating characteristic (ROC) curve was drawn and S/CO threshold was obtained by SPSS 13.0 software. Results Of 202 specimens of initial screening of anti-HCV-positive blood sera, 33 (16%) of them were confirmed negative when detected with RIBA and RNA test. In 92 (46%) RIBA positive samples HCV RNA was found positive in only 30 (33%)of them. All HCV RNA were negative in 77 (38%) indeterminate samples when tested with RIBA. If the indeterminate result tested with RIBA was not included in the statistics analysis, the positive coincidence rate of RIBA compared with I2000 and ECI was 83.2% and 75.2% respectively. When I2000 anti-HCV S/CO ratio was ≥3.4, and ECI anti-HCV S/CO was ≥ 9.1, the positive coincidence rate could achieve 95%. Conclusions In order to ensure 95% true positive ratio, it is the proposed that RIBA test or HCV RNA test should be used if possible, if the S/CO ratios range between 1.0-3.4 detected by the I2000 analyzer and 1.0-9.1 detected by the ECI analyzer. Key words: Hepatitis C antibodies; Immunoblotting; Chemiluminescent measurements; Evaluation studies