酶扩大免疫测定技术与荧光偏振免疫法测定全血环孢素浓度的比较

目的:比较酶扩大免疫测定技术(EMIT)与荧光偏振免疫法(FPIA)测定全血环孢素浓度的差异。方法:通过分别测定高、中、低浓度标准质控品评价各方法的准确度及精密度,并对卫生部室间质控品及99份临床全血环孢素样本进行测定,比较2种方法测定结果的相关性。结果:EMIT与FPIA方法学的相对回收率分别在93.74%～105.73%与99.84%～102.26%之间,日内及日间精密度良好,RSD均小于10%,符合生物样品的测定要求。两方法测定结果具有良好的相关性Y=1.122 1 X+1.783 7,r=0.987,EMIT的测定结果大多低于FPIA测定结果。结论:EMIT法与FPIA法测定环孢素血药浓度结果存在显著性差异,临床应用中应予以关注并作相应调整。     

HPLC法与EMIT法检测血样中甲氨蝶呤浓度的比较研究

目的:比较HPLC法和酶放大免疫法（EMIT）检测血样中甲氨蝶呤（MTX）浓度的相关性。方法:分别用HPLC法和EMIT法测定患者使用大剂量MTX 44 h后的血样,考察2种测定方法的区别和相关程度。结果:HPLC法和EMIT法检测的MTX血浓度差异有统计学意义（P<0.05）,EMIT法测定结果较HPLC法高0.12μmol·L^-1,通过passing-badlok回归分析2种方法具有良好的相关性（r=0.996 2）。结论:HPLC法和EMIT法测定MTX血浆药物浓度结果具有明显差异,在临床进行MTX药物浓度监测中应予以关注并作相应调整。     

室内质量控制在EMIT法监测他克莫司血药浓度中的应用

目的:通过室内质量控制提高血药浓度监测的质量。方法:采用酶放大免疫分析技术(EMIT)法测定他克莫司血药浓度低、中、高质控品各85个点,应用Excel自动作图功能绘制质控图,对监测过程进行回顾性质量分析;分别在21、22、23、24、25℃,测定低、中、高质控品各5份,考察温度对血药浓度测定结果的影响。结果:低、中、高质控品实测值各有9、1、5个点超出质控的允许误差范围;3水平质控的RSD分别为22.6%、14.5%和12.8%;环境温度对EMIT法的监测结果有显著影响。结论:室内质量控制对于应用EMIT法监测他克莫司的血药浓度很重要,可及时预防并纠正各类误差,提高监测结果的精确性,从而对监测结果作出更精确的判断。     

Application of the EMIT 2000 Tacrolimus assay on the Abbott Architect c8000 high volume clinical chemistry analyzer

OBJECTIVES: Evaluation of the performance of the EMIT 2000 Tacrolimus assay on the Abbott Architect c8000 analyzer. DESIGN AND METHODS: Imprecision studies were performed and patient samples were assayed by EMIT assay and by LC-MS/MS. RESULTS: Limit of quantification was established at 2.8 microg/L. A positive bias of 17.5% between results measured on EMIT and on LC-MS/MS was detected. CONCLUSIONS: EMIT 2000 Tacrolimus assay is suitable for automated analyses of Tacrolimus on the Architect c8000.     

EMIT与FPIA法测定肾移植术后患者体内环孢素A血药浓度结果比较

目的 比较酶扩大免疫法（EMIT）和荧光偏振免疫法（FPIA）监测环孢素A（CsA）血药浓度的相关性.方法 收集肾移植患者服药后达稳态的谷浓度血样,分别用EMIT法和FPIA法进行测定,考察两种方法测定结果的相关程度.结果 两种方法测定结果高度相关,差异有显著性.结论 EMIT法和 FPIA法测定CsA血药浓度结果差异具有统计学意义,在CsA治疗药物监测中应予以关注并作相应调整.     

Simultaneous detection of 19 drugs of abuse on dried urine spot by liquid chromatography–tandem mass spectrometry

Background

The lack of specificity of immunoassays for drugs of abuse testing (DAT), and concerns over its cost in conjunction with reflex confirmatory tests prompted us to investigate the combinatorial use of dried urine spot (DUS) and LC–MS/MS as an alternative.

Methods

The method development and validation were performed in accordance with the guidelines published by FDA and CLSI.

Results

In this study we established and validated the precision, accuracy, and linearity of our DUS–LC–MS/MS method, and assessed the recovery, interference, and carryover as well. The linearity check for all 19 analytes demonstrated slopes between 0.94 and 1.04, and R² always greater than 0.99. Between-batch CV for QC at 4 difference levels ranged from 1.1% to 10%, where CV of LLOQ ranged from 1.2% to 12.8% and CV of ULOQ ranged from 0.8% to 5.1%. A concordance study with patient specimens between our method and GC–MS demonstrated 80.8% to 100% agreement. Stability of DUS specimens was assessed up to 30 days and the measured concentrations ranged from 94% to 114% of the 100 ng/mL urine calibrator used for this assessment.

Conclusions

We established and validated a DUS–LC–MS/MS method for DAT that conforms to the guidelines dictated by FDA, CLSI, and SAMHSA. While our method with high sensitivity and specificity provides an alternative diagnostic utility to EMIT immunoassays, it also offers superior solutions in specimen transportation, preservation, and storage. The benefits of our method are apparent in reducing turnaround time and test costs that result in better patient care.     

The EMIT 2000 tacrolimus assay: an application protocol for the Beckman Synchron LX20 PRO analyzer

OBJECTIVE: To develop and evaluate the performance of an application protocol for the EMIT 2000 tacrolimus (Tac) assay on the Beckman Synchron LX20 PRO Analyzer. DESIGN AND METHODS: Precision, accuracy, linearity, and lower limit of quantitation were investigated. Specimens from 212 kidney, liver, heart/heart-lung, and islet cell transplant patients were analyzed and results were compared to those from the Abbott MEIA II assay. A separate population of 232 specimens was coanalyzed by the enzyme-multiplied immunoassay technique (EMIT) assay and liquid chromatography tandem mass spectrometry (LC-MS/MS). RESULTS: Total imprecision was 13.7% and 6.0% at concentrations of 3.4 and 19.1 microg/L, respectively. Recoveries from assayed reference materials ranged from 103% to 109%. A quantitation range of 3.2-30.0 microg/L was validated. The EMIT assay on the LX20 PRO analyzer showed an average negative bias of 1% compared to the MEIA assay and an average positive bias of 17% compared to LC-MS/MS. CONCLUSION: This application for the EMIT 2000 Tac assay on the Beckman Synchron LX20 PRO analyzer enhances the versatility of the immunoassay for routine therapeutic drug monitoring (TDM) of this immunosuppressant in the clinical setting.     

大剂量甲氨蝶呤治疗急性淋巴细胞白血病及淋巴瘤的血药浓度监测与不良反应统计分析

目的探讨大剂量甲氨蝶呤(methotrexate,MTX)治疗急性淋巴细胞白血病(acute lymphoblastic leukemia,ALL)和淋巴瘤的血药浓度监测的临床意义,并统计分析其不良反应。方法选择44例急性淋巴细胞白血病及淋巴瘤患者,使用大剂量甲氨蝶呤(high-dose methotrexate,HD-MTX)后,采用酶放大免疫法测定其血药浓度,观察不良反应发生情况,分析儿童与成人不良反应的区别。结果与成人组比较,儿童组的胃肠道反应和黏膜损伤发生率更高,差异有统计学意义(P<0.05);CMTX48 h>0.4μmol/L者的骨髓抑制及胃肠道反应发生率高于CMTX48 h≤0.4μmol/L者,两组之间差异有统计学意义(P<0.05)。结论 MTX不良反应主要为骨髓抑制、胃肠道反应及黏膜损伤;儿童的胃肠道反应和黏膜损伤发生率高于成人;通过监测MTX的血药浓度有助于及时适量调整甲酰四氢叶酸钙(calcium folinate,CF)解救量,确保临床用药安全有效。