Interlaboratory variability in drug assay: a comparison of quality control data with reanalysis of routine patient samples. I: Anticonvulsant drugs and theophylline. Clinical Pharmacology and Toxicology Study Group, Italian Society for Clinical Biochemist

Abstract:

:The interlaboratory variability in the assay of theophylline and various anticonvulsant drugs was evaluated in a 16-month prospective study by using two independent experimental approaches: (a) a conventional method based on the distribution of quality control (QC) lyophilized human sera spiked with the test drugs (phenytoin, phenobarbital, carbamazepine, valproic acid, primidone, theophylline); and (b) reanalysis by two to four reference laboratories of patients' samples randomly selected among those routinely assayed for phenytoin and theophylline by the 52 participating laboratories. For all tested drugs, precision as assessed by results on spiked QC samples was generally satisfactory, interlaboratory coefficients of variation (CV) being below 18.5% for all drugs tested except primidone (CV = 24.1%) at clinically relevant drug concentrations. For both phenytoin and theophylline, there was a good agreement between results obtained by individual reference laboratories (reference results) on routine samples. The correlation coefficients relating the original values to the means of the reference results were greater than 0.94. It is concluded that interlaboratory variability in the assay of the drugs included in this survey is relatively low not only when assessed by using conventional QC material, but also under strictly routine conditions.

journal_name

Ther Drug Monit

authors

subject

Has Abstract

pub_date

1991-03-01 00:00:00

pages

131-9

issue

2

eissn

0163-4356

issn

1536-3694

journal_volume

13

pub_type

杂志文章
  • Therapeutic drug monitoring reduces toxic drug reactions: a meta-analysis.

    abstract::Therapeutic drug monitoring (TDM) is commonly employed to optimize the dosing of certain drugs, including digoxin, aminoglycosides, theophylline, and phenytoin. Studies were reviewed in order to (a) evaluate the effect of TDM on the occurrence of toxic drug reactions (TDRs) and (b) identify factors that may modify or ...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章,meta分析

    doi:10.1097/00007691-199001000-00013

    authors: Ried LD,Horn JR,McKenna DA

    更新日期:1990-01-01 00:00:00

  • Binding parameters of valproic acid to serum protein in healthy adults at steady state.

    abstract::Two hundred milligrams of valproic acid (VPA) was administered orally to seven healthy adults at 9:00 and 21:00 h for 5 consecutive days, including the morning dose on day 6. On the sixth day, blood samples were drawn at 0, 0.17, 0.33, 0.5, 0.75, 1, 1.5, 3, and 6 h after the morning dose. Binding of VPA to serum prote...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/00007691-199202000-00009

    authors: Kodama Y,Koike Y,Kimoto H,Yasunaga F,Takeyama M,Teraoka I,Fujii I

    更新日期:1992-02-01 00:00:00

  • Liquid chromatography with electrochemical detection for monitoring mebendazole and hydroxymebendazole in echinococcosis patients.

    abstract::A sensitive method is described for the simultaneous determination of mebendazole and hydroxymebendazole using flubendazole as an internal standard. The analytes were isolated with a single chloroform extraction from 1.0 ml of alkalinized plasma or cyst liquid samples. Separation and quantitation were performed with h...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/00007691-198406000-00015

    authors: Oosterhuis B,Wetsteyn JC,van Boxtel CJ

    更新日期:1984-01-01 00:00:00

  • A simple high-performance liquid chromatography assay for simultaneous measurement of adenosine, guanosine, and the oxypurine metabolites in plasma.

    abstract::To study the effect of pharmacologic agents on the biologic fate of adenosine, a reversed-phase high-performance liquid chromatography (HPLC) assay coupled with a solid-phase extraction (SPE) method was developed for simultaneous determination of plasma adenosine, hypoxanthine, xanthine, inosine, guanosine, and uric a...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/00007691-200004000-00007

    authors: Feng JD,Yeung PK

    更新日期:2000-04-01 00:00:00

  • Evaluation of therapeutic drug monitoring of methotrexate in saliva of children with rheumatic diseases.

    abstract::Pediatric patients with leukemia, other malignancies, and rheumatological disease receive methotrexate chronically. Because of the documented correlation between methotrexate levels of compliance and clinical outcome, it is conceivable to verify appropriate systemic exposure to the drug. Saliva sampling may be of pote...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/00007691-199506000-00006

    authors: Press J,Berkovitch M,Laxer R,Giesbrecht E,Verjee Z,Silverman E,Klein J,Koren G

    更新日期:1995-06-01 00:00:00

  • Rapid protein determinations on ultrafiltrates prepared for free phenytoin quantification.

    abstract::Ultrafiltration techniques for the separation of bound and free ligand are dependent on minimal amounts of protein-bound drug leakage through the membrane devices. A dye-impregnated test strip protein assay (Chemstrip-9) provides a rapid, visual assessment of membrane protein leakage. The test strips are sensitive to ...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/00007691-198507030-00014

    authors: Turley CP,Milligan T

    更新日期:1985-01-01 00:00:00

  • Evaluation of MPA and MPAG removal by continuous venovenous hemodiafiltration and continuous venovenous hemofiltration.

    abstract::The study assessed the removal of mycophenolic acid (MPA) and its major glucuronide metabolite (MPAG) during continuous venovenous hemofiltration (CVVHF) and continuous venovenous hemodiafiltration (CVVHDF) in 4 heart transplant recipients treated for at least 6 days with mycophenolate mofetil (MMF) in addition to cyc...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/FTD.0b013e3181633667

    authors: Cussonneau X,Bolon-Larger M,Prunet-Spano C,Bastien O,Boulieu R

    更新日期:2008-02-01 00:00:00

  • Digitalis-like immunoreactive substances in maternal and umbilical cord plasma: a comparative sensitivity study of fluorescence polarization immunoassay and microparticle enzyme immunoassay.

    abstract::Digitalis-like immunoreactive substances (DLIS) obtained from maternal and umbilical cord plasma at delivery were measured by fluorescence polarization immunoassay (FPIA; TDX, Abbott) and microparticle enzyme immunoassay (MEIA; IMX, Abbott). In each sample, concentrations of dehydroepiandrosterone, dehydroepiandroster...

    journal_title:Therapeutic drug monitoring

    pub_type: 临床试验,杂志文章

    doi:10.1097/00007691-200304000-00015

    authors: Ijiri Y,Hayashi T,Kamegai H,Ohi K,Suzuki K,Kitaura Y,Takenaka H

    更新日期:2003-04-01 00:00:00

  • Sorption of thiotepa to polyurethane catheter causes falsely elevated plasma levels.

    abstract::Central venous access catheters are commonly used in clinical oncology. The double lumen variant is applied in pharmacokinetic studies for simultaneous administration and blood sampling when frequent blood collections are necessary. Occlusion of one lumen, a common complication, necessitates the investigator perform b...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/00007691-200306000-00002

    authors: de Jonge ME,Mathôt RA,van Dam SM,Rodenhuis S,Beijnen JH

    更新日期:2003-06-01 00:00:00

  • Screening procedure for detection of diuretics and uricosurics and/or their metabolites in human urine using gas chromatography-mass spectrometry after extractive methylation.

    abstract::A gas chromatography-mass spectrometry (GC-MS)-based screening procedure was developed for the detection of diuretics, uricosurics, and/or their metabolites in human urine after extractive methylation. Phase-transfer catalyst remaining in the organic phase was removed by solid-phase extraction on a diol phase. The com...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/01.ftd.0000160719.96445.91

    authors: Beyer J,Bierl A,Peters FT,Maurer HH

    更新日期:2005-08-01 00:00:00

  • The effect of coadministration of duloxetine on steady-state serum concentration of risperidone and aripiprazole: a study based on therapeutic drug monitoring data.

    abstract::Previous studies have categorized duloxetine as a moderate inhibitor of CYP2D6. The aim of the present study was to investigate the potential interactions between duloxetine and the two CYP2D6 substrates risperidone and aripiprazole in psychiatric patients. Serum concentration data from patients treated with risperido...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/FTD.0b013e3181fc50d5

    authors: Hendset M,Molden E,Enoksen TB,Refsum H,Hermann M

    更新日期:2010-12-01 00:00:00

  • Evaluation of pharmacokinetic methods used to estimate caffeine clearance and comparison with a Bayesian forecasting method.

    abstract::Simplified pharmacokinetic methods have been used to estimate caffeine clearance in subjects with liver disease. There is a need to have a reliable, easy to implement method for research and possible clinical use. This study evaluates the use of Bayesian pharmacokinetic forecasting techniques to estimate caffeine clea...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/00007691-199802000-00015

    authors: Denaro CP,Jacob P 3rd,Benowitz NL

    更新日期:1998-02-01 00:00:00

  • Ipecac toxicity in "Munchausen syndrome by proxy".

    abstract::The authors report a case that offers insight into the diagnostic challenges of "Munchausen Syndrome by Proxy." Initial presentation with history of fever and later with intractable vomiting led to invasive and expensive diagnostic evaluation before confirming the diagnosis. Certain toxic effects of emetine were clini...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/00007691-199904000-00021

    authors: Bader AA,Kerzner B

    更新日期:1999-04-01 00:00:00

  • Within-patient variability of mycophenolic acid exposure: therapeutic drug monitoring from a clinical point of view.

    abstract::Exposure to mycophenolic acid (MPA) is highly variable among patients on standard dose mycophenolate mofetil (MMF) therapy. In addition, MPA exposure increases with time posttransplant and exposure is predictive for the development of acute rejection. Consequently, therapeutic drug monitoring (TDM) of MPA may improve ...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章,评审

    doi:10.1097/01.ftd.0000194504.62892.b2

    authors: van Hest RM,Mathot RA,Vulto AG,Ijzermans JN,van Gelder T

    更新日期:2006-02-01 00:00:00

  • Acute antidepressant response and plasma levels of bupropion and metabolites in a pediatric-aged sample: an exploratory study.

    abstract::Studies examining associations between antidepressant response and plasma levels of bupropion and its metabolites have yielded contradictory findings. There have been no such studies in youth. This study explored such associations in 8 boys and 8 girls, age 11 to 17 years, all prescribed bupropion sustained release (S...

    journal_title:Therapeutic drug monitoring

    pub_type: 临床试验,杂志文章

    doi:10.1097/01.ftd.0000197093.92559.7a

    authors: Daviss WB,Perel JM,Brent DA,Axelson DA,Rudolph GR,Gilchrist R,Nuss S,Birmaher B

    更新日期:2006-04-01 00:00:00

  • Highly specific quantification of ergotamine in urine, blood, and hair samples by liquid chromatography-tandem mass spectrometry.

    abstract::Ergotamine has been used for therapeutic purposes since the 1950s, usually to treat vascular headache. It is highly toxic and in large, repeated doses can produce all the symptoms of ergot poisoning. A selective and sensitive method, based on liquid chromatography-tandem mass spectrometry (LC-MS2), has been developed ...

    journal_title:Therapeutic drug monitoring

    pub_type: 临床试验,杂志文章

    doi:10.1097/FTD.0b013e318067dfe7

    authors: Favretto D,Frison G,Vogliardi S,Ferrara SD

    更新日期:2007-06-01 00:00:00

  • Analysis of topiramate and its metabolites in plasma and urine of healthy subjects and patients with epilepsy by use of a novel liquid chromatography-mass spectrometry assay.

    abstract::A novel liquid chromatography-mass spectrometry (LC-MS) method was developed and validated for quantification of topiramate (TPM) and its metabolites 10-hydroxy topiramate (10-OH-TPM), 9-hydroxy topiramate (9-OH-TPM), and 4,5-O-desisopropylidene topiramate (4,5-diol-TPM) in plasma and urine. The method uses 0.5 mL of ...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/00007691-200306000-00012

    authors: Britzi M,Soback S,Isoherranen N,Levy RH,Perucca E,Doose DR,Maryanoff BE,Bialer M

    更新日期:2003-06-01 00:00:00

  • Time course of appearance of cotinine in human beard hair after a single dose of nicotine.

    abstract::The time course of appearance of cotinine in saliva and in daily collections of beard clippings was monitored by gas chromatography with mass spectrometry in six volunteers who were nonsmokers following a single 30-min buccal administration of nicotine as a chewing gum. Salivary cotinine concentrations reached a plate...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/00007691-199504000-00016

    authors: Gwent SH,Wilson JF,Tsanaclis LM,Wicks JF

    更新日期:1995-04-01 00:00:00

  • Risperidone and Venlafaxine Metabolic Ratios Strongly Predict a CYP2D6 Poor Metabolizing Genotype.

    abstract:PURPOSE:To investigate the predictive value of the risperidone and venlafaxine metabolic ratios and CYP2D6 genotype. METHODS:The determination of risperidone, 9-hydroxyrisperidone, and venlafaxine, O-desmethylvenlafaxine, N-desmethylvenlafaxine and CYP2D6 genotype was performed in 425 and 491 patients, respectively. T...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/FTD.0000000000000251

    authors: Mannheimer B,Haslemo T,Lindh JD,Eliasson E,Molden E

    更新日期:2016-02-01 00:00:00

  • Assessment of VerifyNow P2Y12 assay accuracy in evaluating clopidogrel-induced platelet inhibition.

    abstract::The emergence of point-of-care assays enabling bedside testing such as the VerifyNow P2Y12 system might prove useful in clinical settings. The aim of this study was to evaluate the ability of the VerifyNow P2Y12 assay to estimate the inhibition of platelet aggregation provided by clopidogrel in the absence of baseline...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章,随机对照试验

    doi:10.1097/FTD.0b013e3181757c59

    authors: Lordkipanidzé M,Pharand C,Nguyen TA,Schampaert E,Diodati JG

    更新日期:2008-06-01 00:00:00

  • Accurately Achieving Target Busulfan Exposure in Children and Adolescents With Very Limited Sampling and the BestDose Software.

    abstract:BACKGROUND:Busulfan dose adjustment is routinely guided by plasma concentration monitoring using 4-9 blood samples per dose adjustment, but a pharmacometric Bayesian approach could reduce this sample burden. METHODS:The authors developed a nonparametric population model with Pmetrics. They used it to simulate optimal ...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/FTD.0000000000000276

    authors: Neely M,Philippe M,Rushing T,Fu X,van Guilder M,Bayard D,Schumitzky A,Bleyzac N,Goutelle S

    更新日期:2016-06-01 00:00:00

  • Free and total plasma concentrations of carbamazepine and carbamazepine-10,11-epoxide in epileptic patients: diurnal fluctuations and relationship with side effects.

    abstract::The diurnal fluctuations in free and total plasma levels of carbamazepine (CBZ) and carbamazepine-10,11-epoxide (CBZ-E) and their relationship with intermittent side effects were examined in 10 epileptic patients stabilized on chronic CBZ therapy alone or in combination with phenobarbital (PB). With a t.i.d. or q.i.d....

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/00007691-198412000-00005

    authors: Riva R,Contin M,Albani F,Perucca E,Ambrosetto G,Gobbi G,Cortelli P,Procaccianti G,Baruzzi A

    更新日期:1984-01-01 00:00:00

  • Carbamazepine and its epoxide: an open study of efficacy and side effects after carbamazepine dose increment in refractory partial epilepsy.

    abstract::We evaluated the efficacy, development of adverse effects, and possible correlation between the plasma concentration of carbamazepine (CBZ) and its major metabolite, carbamazepine-10,11-epoxide (CBZ-E), in a group of epileptic patients in whom selective increases in CBZ doses were made. Eighteen patients with refracto...

    journal_title:Therapeutic drug monitoring

    pub_type: 临床试验,杂志文章

    doi:

    authors: Semah F,Gimenez F,Longer E,Laplane D,Thuillier A,Baulac M

    更新日期:1994-12-01 00:00:00

  • Enantioselective analysis of citalopram and metabolites in adolescents.

    abstract::Studies of the antidepressant effect and pharmacokinetics of citalopram have been performed in adults, but the effects on children and adolescents have only been studied to a minor extent despite its increasing use in these age groups. The aim of this study was to investigate a group of adolescents treated for depress...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/00007691-200112000-00011

    authors: Carlsson B,Olsson G,Reis M,Walinder J,Nordin C,Lundmark J,Scordo MG,Dahl ML,Bengtsson F,Ahlner J

    更新日期:2001-12-01 00:00:00

  • Evaluation of cross-reactivity of urinary digoxin-like substance in different radioimmunoassays.

    abstract::For the accuracy of routine monitoring of digoxin and digitoxin it seems important to get information on the cross-reactivity of endogenous digitalis-like substances (EDLS). To obtain EDLS, urine was passed on Sep-Pak columns and eluted in fractions by increasing concentrations of acetonitrile. Dilution series of two ...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:

    authors: Vinge E,Ekman R

    更新日期:1988-01-01 00:00:00

  • Subtherapeutic Linezolid Concentration in a Patient With Bullous Pemphigoid Complicated by Methicillin-Resistant Staphylococcus aureus Infection: A Case Study.

    abstract::We presented a case of subtherapeutic linezolid concentration in a patient with bullous pemphigoid characterized by large area skin anabrosis complicated by methicillin-resistant Staphylococcus aureus infections. ...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/FTD.0000000000000758

    authors: Chen C,Zhang M,Chen H,Fang J

    更新日期:2020-08-01 00:00:00

  • Ultra fast liquid chromatography-tandem mass spectrometry routine method for simultaneous determination of cyclosporin A, tacrolimus, sirolimus, and everolimus in whole blood using deuterated internal standards for cyclosporin A and everolimus.

    abstract::Specific chromatographic methods for the measurement of cyclosporin A, tacrolimus, sirolimus, and everolimus blood levels in patients with organ transplants are time consuming when large numbers of samples must be processed. The authors developed a robust and fast (1 minute) online solid-phase extraction liquid chroma...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/FTD.0b013e3181c49a00

    authors: Meinitzer A,Gartner G,Pilz S,Stettin M

    更新日期:2010-02-01 00:00:00

  • Spurious phenobarbital levels by fluorescence polarization immunoassay using TDx analyzer in patients with renal disease.

    abstract::Results of phenobarbital analyses are presented for 14 patients with chronic renal failure, and compared using gas-liquid chromatography (GLC), enzyme immunoassay (EIA), and fluorescence polarization immunoassay (FPIA). Correlation of FPIA with GLC and EIA was poor. ...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/00007691-198409000-00019

    authors: Bridges RR,Jennison TA

    更新日期:1984-01-01 00:00:00

  • A rapid and simple microassay for lidocaine in human blood plasma using gas-liquid chromatography with nitrogen detection.

    abstract::Lidocaine is widely used in antiarrhythmic therapy, and the need to monitor the drug concentration in the blood of patients receiving lidocaine is well established. We have developed a new assay for lidocaine designed for the routine clinical therapeutic drug monitoring laboratory. A 100-microliter aliquot of blood pl...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/00007691-198102000-00010

    authors: Gal J,Freedman MD,Kumar E,Freed CR

    更新日期:1981-01-01 00:00:00

  • Opioid receptor A118G polymorphism does not affect the consumption of sufentanil and ropivacaine by patient-controlled epidural analgesia after cesarean section.

    abstract:BACKGROUND:Previous reports have suggested that polymorphism of the opioid receptor A118G affects the efficacy of opioid analgesia. The aim of this study was to investigate whether such polymorphism contributed to variability in epidural mixture (sufentanil plus ropivacaine) requirements through patient-controlled epid...

    journal_title:Therapeutic drug monitoring

    pub_type: 杂志文章

    doi:10.1097/FTD.0000000000000112

    authors: Xu GH,Gao M,Sheng QY,Liu XS,Gu EW

    更新日期:2015-02-01 00:00:00