A Case of Elevated Troponin I Level After Packed Red Blood Cell Transfusion With Normal Coronary Angiography.

Other than acute coronary syndrome (ACS), many clinical conditions are associated with increased cardiac troponin I (cTnI) levels. Conditions such as pulmonary embolism, acute heart failure, myocarditis, sepsis, and renal failure are commonly reported as underlying causes. Analytical interference with the cTnI assay can also lead to falsely elevated troponin I levels. That can happen due to multiple causes such as fibrin clots, heterophile antibodies, microparticles contained in the sample, rheumatoid factor, interference by bilirubin, hemolysis, and elevated alkaline phosphatase activity. Herein, we present the case of a 66-year-old female who presented with pleuritic chest pain and had a cTnI of 35.5 ng/mL post-transfusion of three units of packed red blood cells. The patient had a complete ischemic workup for ACS, including coronary angiography, which was negative for coronary artery disease.

N-glycosylation mutations within hepatitis B virus surface major hydrophilic region contribute mostly to immune escape.

BACKGROUND & AIMS: HBV immune escape represents a challenge to prevention, diagnosis, and treatment of hepatitis B. Here, we analyzed the molecular and clinical characteristics of HBV immune escape mutants in a Chinese cohort of chronically infected patients. METHODS: Two hundred sixteen patients with HBsAg and anti-HBs were studied, with one hundred eighty-two HBV carriers without anti-HBs as a control group. Recombinant HBsAg bearing the most frequent N-glycosylation mutations were expressed in CHO and HuH7 cells. After confirming N-glycosylation at the most frequent sites (129 and 131), together with inserted mutations, functional analysis were performed to study antigenicity and secretion capacity. RESULTS: One hundred twenty-three patients had the wild-type HBs gene sequence, 93 patients (43%) had mutants in the major hydrophilic region (MHR), and 47 of the 93 patients had additional N-glycosylation mutations, which were transmitted horizontally to at least 2 patients, one of whom was efficiently vaccinated. The frequency of N-glycosylation mutation in the case group was much higher than that of the control group (47/216 vs. 1/182). Compared with wild-type HBsAg, HBsAg mutants reacted weakly with anti-HBs using a chemiluminescent microparticle enzyme immunoassay. Native gel analysis of secreted virion in supernatants of transfected HuH7 cells indicated that mutants had better virion enveloping and secretion capacity than wild-type HBV. CONCLUSIONS: Our results suggest that specific HBsAg MHR N-glycosylation mutations are implicated in HBV immune escape in a high endemic area.

Study on conformance between two kinds of detection method of anti-HBs antibody / 国际检验医学杂志

Objective To analyze the conformance between the quantitative and qualitative tests of hepatitis B surface antibody (anti-HBs).Methods The chemiluminecence microparticle enzyme immunoassay(CMIA)was adopted to quantitatively detect anti-HBs and the enzyme linked immunosorbent assay(ELISA)was adopted to qualitatively detect anti-HBs.Results With the CMIA as the reference experiment,Se ,Sp ,J ,PV+ and PV-of anti-HBs detected by ELISA were 0.95,0.53,0.48,0.74 and 0.88 respec-tively,k=0.51;when the absorbance was 0.400 9,Se ,Sp ,J ,PV+ and PV-were 0.50,0.95,0.45,0.93 and 0.43 respectively;for the samples exceeding the absorbance range of 0.104 3 -0.400 9,Se ,Sp ,J ,PV+ and PV-qualitatively detected by ELISA were 0.90,0.91,0.81,0.93 and 0.88 respectively,k =0.81.Conclusion Determining cutoff value with the absorbance value 0.105 as the ELISA detection result has the good detection sensitivity(Se =0.95)and the better negative prediction value(PV-=0.88),the negative anti-HBs detected by ELISA may be considered that the anti-HBs concentration was less than 10 mIU/mL without the conservation value;when the sample absorbance ≥0.400 9,the anti-HBs concentration is ≥10 mIU/mL,which may be considered to have the conservation value;the gray area range of anti-HBs detected by ELISA is mainly the absorbance of 0.105-0.400 9,the true anti-HBs level should be quantitatively detected.

Performance Evaluation of Immunoassay Detection of HBsAg Mutants and Their Clinical Significance in the High Risk Groups

BACKGROUND: False negative results have been reported in the immunodetection of hepatitis B virus (HBV) because of the existence of the various mutants of the virus, causing most suppliers to try to develop superior reagents by using highly sensitive and specific monoclonal or polyclonal antibodies. In this study, we evaluated the effectiveness of 3 newly developed reagents by major manufacturers by adopting automated methods with increased sensitivity and specificity in the detection and discrimination of native and recombinant mutant antigens. METHODS: We analyzed samples confirmed positive for hepatitis B surface antigen (HBsAg), high-risk samples from chronic hepatitis patients treated with antiviral agents, and samples from patients who had undergone liver transplantation and were treated with high-dose hepatitis B immunoglobulin (HBIG) by using reagents and systems newly developed by Abbott Laboratories (USA), Roche Diagnostics (Germany), and Siemens Healthcare Diagnostics (USA). Recombinant sample panels from these manufacturers with low and high concentrations were also analyzed for comparing the 3 reagents. RESULTS: There were no discrepant results among the various selected patient groups; however, for the recombinant mutant panels, all of the 3 reagents showed highly positive detection rates for their corresponding mutant panels, but showed relatively discrepant mutant detection rates when cross-tested with the other mutant panels. Detection rates of the HBsAg mutant panels were higher at a higher concentration of the mutant samples, but were lower for the same mutant receptor sites at a lower concentration. CONCLUSIONS: The 3 major detection methods seem to recognize the major native mutants commonly encountered in clinical practice. However, in the case of recombinant mutants, we believe that our data are not to be interpreted as a reference standard for any reagent, because the results can only be validated for the reagents' corresponding mutant panels; such results tend to be mutually exclusive, and the enough concentration of mutants was required to be adjusted for a comparative analysis.

Performance Evaluation of 3 Kinds of HBsAg Qualitative Assays and 2 Kinds of Quantitative Assays

BACKGROUND: Currently used techniques for quantitation of HBsAg often yield discordant results; therefore, development of quantitation techniques that can detect HBsAg with high accuracy has become very important. Recent advances have led to the development of several HBsAg detection systems. Here, we evaluated the performance of 3 newly developed detection systems, which can detect HBsAg both qualitatively and quantitavely, and determined the concordance among their results. METHODS: Four hundred and thirty two samples assigned to 4 groups-patient group, dilution group, weakly reactive group, and linearity group- were subjected to qualitative and quantitative detection of HBsAg by using the 3 systems developed by 3 major manufacturers; Abbott Architect, Roche E170 and Siemens Centaur XP. RESULTS: The results for the qualitative analyses were closely concordant among the three systems (98.3%) for all 432 samples. In 123 samples that were determined as HBsAg-negative, E170 (76%) distributed frequently at the upper half level (0.5-1.0) of negative reference range, compared with Architect (11%) and Centaur XP (22%). In particular, in 65 samples that were diluted from the strongly positive samples to obtain weakly positive samples, the average index values obtained using Architect (3.6 S/CO), E170 (4.2 COI) and Centaur XP (11.4 index value) differed significantly (P<0.0001). In the antiviral treatment group and the post-liver transplantation group, no inconsistency was observed among the results of the qualitative and quantitative assays. In the 18-fold serially diluted samples, no linearity was observed. CONCLUSIONS: Because of the possibility of false-positive detection in the HBsAg-negative samples, regular management of equipment and appropriate selection of reagents are very important. In weakly positive samples, quantitative assay has not to be replaced for qualitative assay. Therefore, the qualitative assays should be used for screening the samples, whereas the quantitative assays should be used for monitoring the Hepatitis B virus (HBV) load in the samples determined as HBsAg-positive. The qualitative index value should not be interpreted as a quantitative measure of HBV load.

Value of the Serum CA125 Level in Diagnosing Epithelial Ovarian Cancer / 医学研究杂志

Objective To evaluate the role of serum CA125 level in diagnosing the epithelial ovarian tumor.Methods Serum CA125 level of seventy-two patients who were operated for epithelial ovarian tumor between Apr 2005 and Jun 2007 in PUMC hospital were recruited and analyzed retrospectively.Using microparticle enzyme immunoassay(MEIA) to determine the serum CA125 level,and evaluate the serum CA125 level in diagnosing epithelial ovarian cancer.Results The CA125 was higher than 35?/ml in 35/39 ovarian serous cystadenocarcinoma cases with 89.7% positive rate,CA125 was higher than 35?/ml in 9/12 ovarian borderline serous cystadenoma with 75% positive rate,and CA125 was higher than 35?/ml in 4/21 ovarian serous cystadenoma with 19% positive rate.Conclusion The serum CA125 level before operation can predict benign epithelial tumor or epithelial ovarian cancer.

Comparison on two methods of HPLC-MS/MS and MEIA in monitoring the tacrolimus concentrations for organ transplantation patients / 中国临床药理学与治疗学

AIM: To compare two methods of HPLC-MS/MS and MEIA to monitor the tacrolimus concentrations for organ transplantation patient.METHODS: After developing and validating the HPLC-MS/MS method to determine the concentrations of tacrolimus,the tacrolimus samples were quantitated by two methods of HPLC-MS/MS and MEIA,respectively.Evaluate two methods by statistical analysis of quantitative results.RESULTS: The mean concentration were(4.86?0.46) ng/mL by HPLC-MS/MS and(5.52?0.43) ng/mL by MEIA.The coefficient correlation of two methods was 0.8771,and the two methods have good correlations in statistics.The mean concentration ratio was(90.3?5.3)%.CONCLUSION: The HPLC-MS/MS method is a more precise method for to determining the effective concentration of tacrolimus,which is suitable for daily TDM.