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1.
Ther Drug Monit ; 39(4): 457-460, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28700524

RESUMO

BACKGROUND: Valproic acid (VPA) is a widely prescribed medicine, and acute toxicity is possible. As such, it should be included in any nontargeted urine drug screening method. In many published liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS/MS) methods, VPA is usually measured using a pseudo-multiple reaction monitoring (MRM) transition. We investigate a simple ultra-high-performance liquid chromatography-quadrupole time-of-flight (QTof) approach to detect the presence of VPA with more confidence. METHODS: Three commercially sourced VPA metabolites were characterized and added to a nontargeted high-resolution MS urine drug screening method. All analyses were performed on a Waters Xevo G2-XS LC-QTof in negative electrospray ionization mode. The mass detector was operated in MS mode, and data were processed with UNIFI software. Sixty-eight patient urine samples, which were previously identified by a well-established gas chromatography-MS method as containing VPA, were analyzed on the Waters Xevo G2-XS LC-QTof, to validate this approach. RESULTS: VPA metabolite standards were characterized, and their detection data were added to the broad drug screening library. VPA metabolites were readily detectable in the urine of patients taking VPA. CONCLUSIONS: The inclusion of characterized VPA metabolites provides a simple and reliable method enabling the detection of VPA in nontargeted urine drug screening.


Assuntos
Anticonvulsivantes/urina , Espectrometria de Massas em Tandem/métodos , Ácido Valproico/urina , Cromatografia Líquida de Alta Pressão/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Urinálise/métodos
2.
Clin Endocrinol (Oxf) ; 80(6): 905-10, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24372054

RESUMO

OBJECTIVE: Selenium is effective in improving quality of life and reducing the progression of active Graves' orbitopathy. The effect of correcting relative selenium deficiency on improving Graves' orbitopathy is unknown, as baseline selenium levels have not previously been measured. The study aims to determine whether serum selenium levels are reduced in patients with Graves' disease with orbitopathy (GO) compared with without orbitopathy (GD). DESIGN: A prospective, case-control study performed between 2009 and 2012 at endocrine and ophthalmology clinics in Australia. PATIENTS: A total of 198 patients with Graves' disease participated in the study: 101 with Graves' orbitopathy and 97 without Graves' orbitopathy. MEASUREMENTS: Serum selenium levels in both groups. RESULTS: Mean serum selenium levels were significantly lower in GO (1·10 ± 0·18 µm) than in GD (1·19 ± 0·20 µm) (P = 0·001). Mean selenium levels appeared to decrease in parallel with increasing severity of GO; selenium level was 1·19 ± 0·20 µm in GD, 1·10 ± 0·19 µm in moderate-to-severe GO and 1·09 ± 0·17 µm in sight-threatening GO (P = 0·003). Serum selenium levels remained significantly lower in GO after adjusting for age, smoking status, thyroidectomy, radioactive iodine treatment and residential location. CONCLUSION: Serum selenium levels are lower in patients with GO compared with GD in an Australian study population with marginal selenium status. Relative selenium deficiency may be an independent risk factor for orbitopathy in patients with Graves' disease.


Assuntos
Doença de Graves/sangue , Oftalmopatia de Graves/sangue , Selênio/sangue , Idoso , Austrália , Estudos de Casos e Controles , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Fatores de Risco
3.
BMJ Open ; 14(6): e083635, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951004

RESUMO

INTRODUCTION: Critically ill patients are at risk of suboptimal beta-lactam antibiotic (beta-lactam) exposure due to the impact of altered physiology on pharmacokinetics. Suboptimal concentrations can lead to treatment failure or toxicity. Therapeutic drug monitoring (TDM) involves adjusting doses based on measured plasma concentrations and individualising dosing to improve the likelihood of improving exposure. Despite its potential benefits, its adoption has been slow, and data on implementation, dose adaptation and safety are sparse. The aim of this trial is to assess the feasibility and fidelity of implementing beta-lactam TDM-guided dosing in the intensive care unit setting. METHODS AND ANALYSIS: A beta-lactam antibiotic Dose AdaPtation feasibility randomised controlled Trial using Therapeutic Drug Monitoring (ADAPT-TDM) is a single-centre, unblinded, feasibility randomised controlled trial aiming to enroll up to 60 critically ill adult participants (≥18 years). TDM and dose adjustment will be performed daily in the intervention group; the standard of care group will undergo plasma sampling, but no dose adjustment. The main outcomes include: (1) feasibility of recruitment, defined as the number of participants who are recruited from a pool of eligible participants, and (2) fidelity of TDM, defined as the degree to which TDM as a test is delivered as intended, from accurate sample collection, sample processing to result availability. Secondary outcomes include target attainment, uptake of TDM-guided dosing and incidence of neurotoxicity, hepatotoxicity and nephrotoxicity. ETHICS AND DISSEMINATION: This study has been approved by the Alfred Hospital human research ethics committee, Office of Ethics and Research Governance (reference: Project No. 565/22; date of approval: 22/11/2022). Prospective consent will be obtained and the study will be conducted in accordance with the Declaration of Helsinki. The finalised manuscript, including aggregate data, will be submitted for publication in a peer reviewed journal. ADAPT-TDM will determine whether beta-lactam TDM-guided dose adaptation is reproducible and feasible and provide important information required to implement this intervention in a phase III trial. TRIAL REGISTRATION NUMBER: Australian New Zealand Clinical Trials Registry, ACTRN12623000032651.


Assuntos
Antibacterianos , Estado Terminal , Monitoramento de Medicamentos , Estudos de Viabilidade , beta-Lactamas , Humanos , Monitoramento de Medicamentos/métodos , Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Estado Terminal/terapia , beta-Lactamas/administração & dosagem , beta-Lactamas/farmacocinética , Ensaios Clínicos Controlados Aleatórios como Assunto , Unidades de Terapia Intensiva
4.
J Anal Toxicol ; 47(3): 263-270, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36367744

RESUMO

Immunoassays are routinely used to provide rapid urine drug screening results in the clinical setting. These screening tests are prone to false-positive results and ideally require confirmation by mass spectrometry. In this study, we have examined a large number of urine specimens where drugs other than amphetamines may have caused a false-positive amphetamine immunoassay screening result. Urine drug screens (12,250) in a clinical laboratory that used the CEDIA amphetamine/ecstasy method were reviewed for false-positive results over a 6-year period (2015-2020). An additional 3,486 referred samples, for which confirmatory--mass spectrometry was requested, were also reviewed. About 86 in-house samples and 175 referral samples that were CEDIA false-positive screens were further analyzed by an LC-QTOF general unknown screen. Potential cross-reacting drugs were identified, and their molecular similarities to the CEDIA targets were determined. Commercial standards were also analyzed for cross-reactivity in the amphetamine/ecstasy CEDIA screen. Positive amphetamine results in 3.9% of in-house samples and 9.9% of referred tests for confirmatory analysis were false positive for amphetamines. Of these false-positive specimens, on average, 6.8 drugs were detected by the LC-QTOF screen. Several drugs were identified as possible cross-reacting drugs to the CEDIA amphetamine/ecstasy assay. Maximum common substructure scores for 70 potential cross-reacting compounds were calculated. This was not helpful in identifying cross-reacting drugs. False-positive amphetamine screens make up to 3.9-9.9% of positive amphetamine screens in the clinical laboratory. Knowledge of cross-reacting drugs may be helpful when mass spectrometry testing is unavailable.


Assuntos
N-Metil-3,4-Metilenodioxianfetamina , Detecção do Abuso de Substâncias , Detecção do Abuso de Substâncias/métodos , Anfetaminas/urina , Anfetamina , Imunoensaio/métodos , Espectrometria de Massas
5.
Clin Biochem ; 95: 66-72, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33989561

RESUMO

OBJECTIVE: Validation of a non-targeted method for urine drug screening (UDS) by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF), and comparison to an established GC-MS method in a hospital setting. METHODS: 217 UDS specimens sent to a quaternary hospital pathology department, were analysed by a CEDIA® immunoassay screen (six drug panels; amphetamines, barbiturates, benzodiazepines, cocaine metabolites, cannabinoids and opiates) on an Abbott Architect instrument. Specimens were subsequently analysed by an established non-targeted qualitative GC-MS method and results compared with a general unknown screening method by LC-QTOF that was under evaluation as a replacement method. RESULTS: 42 selected drugs were evaluated; limits of identification ranged from 2 to 100 µg/L and most drugs (n = 39) were stabile for 24 h after preparation. Matrix effects greater than 25% were observed in seven of the selected drugs. 87% of the specimens tested positive to 1 or more drug panels in a CEDIA® screen. A total of 537 positive drug findings were identified by GC-MS compared to 1,267 positive findings by LC-QTOF. On average, each GC-MS screen identified 2.5 ± 1.8 drugs and the LC-QTOF screen identified 5.8 ± 3.2 drugs. No drugs were identified in 11.3% of the GC-MS screens, whereas drugs were detected in 99% of these by the LC-QTOF. In almost all instances, the LC-QTOF screen could provide mass spectrometric confirmatory results of positive immunoassay screens and was able to identify a wider range of additional drugs and drug metabolites. CONCLUSIONS: The described general unknown screening (non-targeted, qualitative) LC-QTOF method can detect a larger range of drugs encountered in a hospital setting. The method has been shown to be suitable for comprehensive toxicology screening in a clinical toxicology laboratory.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Toxicologia Forense/métodos , Espectrometria de Massas/métodos , Detecção do Abuso de Substâncias/métodos , Urinálise/métodos , Adolescente , Toxicologia Forense/instrumentação , Hospitais Universitários , Humanos , Drogas Ilícitas/análise , Imunoensaio , Transtornos Relacionados ao Uso de Substâncias/urina , Urinálise/instrumentação , Adulto Jovem
6.
J Anal Toxicol ; 43(4): e23-e27, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30566569

RESUMO

BACKGROUND: Ayahausca is an ethnobotanical drink of South America and the compound dimethyltryptamine (DMT) is primarily responsible for the hallucinogenic effects. DMT has a short half-life and its detection in urinary drug screens is challenging. We investigate a simple alternate approach to detect ayahuasca consumption by relying on other constituents of the drink, the ß-carboline harmala alkaloids. METHODS: Three commercially sourced harmala alkaloids were characterized and added to a non-targeted high-resolution mass spectrometry urine drug screening method. All analyses were performed on a Waters Xevo G2-XS LC-QTof, in positive electrospray ionization mode. The mass detector was operated in MSE mode and data processed with UNIFI™ software. A urine specimen from a patient suspected to have consumed ayahuasca was analyzed by a non-targeted drug screen. RESULTS: The harmala alkaloids: harmine, harmaline and tetrohydroharmaline (THH) were characterized and their detection data added to the toxicology screening library. Harmaline and THH were detected in the patient's urine specimen. CONCLUSION: The inclusion of the harmala alkaloids into the drug screen method library may enable the detection of ayahuasca use in patients that undergo non-targeted drug screen.


Assuntos
Banisteriopsis/química , Alcaloides de Harmala/urina , Extratos Vegetais/urina , Detecção do Abuso de Substâncias/métodos , Transtornos Relacionados ao Uso de Substâncias/urina , Adulto , Antimaníacos/uso terapêutico , Antipsicóticos/uso terapêutico , Cromatografia Líquida , Alucinógenos/toxicidade , Alucinógenos/urina , Humanos , Masculino , Espectrometria de Massas , N,N-Dimetiltriptamina/toxicidade , N,N-Dimetiltriptamina/urina , Olanzapina/uso terapêutico , Psicoses Induzidas por Substâncias/tratamento farmacológico , Resultado do Tratamento , Ácido Valproico/uso terapêutico
7.
Case Reports Hepatol ; 2019: 6741213, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31214366

RESUMO

Turmeric is a commonly used oral herbal supplement with purported anti-inflammatory and antineoplastic properties. It is promoted as safe, with limited reports of severe adverse effects directly related to oral turmeric thus far in the literature. Herein we report two cases of turmeric supplement induced severe hepatitis. These cases highlight the need for physicians to be aware of patients taking this common supplement and the potential risks that exist.

8.
Pathology ; 50(5): 536-539, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29937233

RESUMO

Cocaine use in Australia is increasing, with approximately 2.5% of the surveyed population having used cocaine. In the USA, levamisole, a widely used anti-helminthic veterinary drug has been increasingly detected as a cutting agent in cocaine seizures. Levamisole is known to cause agranulocytosis in humans. We ascertained the prevalence of levamisole-adulterated cocaine, detectable in the urine from patients that had undergone a pathology request for a urine drug screen. We assayed routinely requested urines that were positive for cocaine on immunoassay with liquid chromatography high resolution quadrupole time of flight mass spectrometry (LC-QToF). We investigated available urine samples from a period of 2 years that had a positive result for cocaine. In addition, we examined samples that were below the cut-off for cocaine on immunoassay. Specimens were analysed for the presence of levamisole and other 'unknown' drugs. In the period under investigation the laboratory examined 3665 urine samples for cocaine: 1.4% (n = 51) of the samples were positive for cocaine by immunoassay and half of these (n = 26, 51%) were further examined by LC-QToF. In addition, we examined 10 samples that were negative by immunoassay (as defined by AS/NZS 4308:2008). Levamisole was detected in the urine of cocaine users in approximately 75% of cases. Other illicit drugs were also frequently found in this cohort. The most common illicit drugs detected were methamphetamine, ecstasy and cannabis. Australian cocaine is widely adulterated with levamisole. Cocaine users are at risk of levamisole related health problems in addition to the problems related to cocaine.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/urina , Cocaína/urina , Levamisol/urina , Adolescente , Adulto , Idoso , Austrália , Cocaína/efeitos adversos , Transtornos Relacionados ao Uso de Cocaína/diagnóstico , Contaminação de Medicamentos/prevenção & controle , Humanos , Masculino , Metanfetamina/urina , Pessoa de Meia-Idade , Adulto Jovem
9.
J Appl Lab Med ; 3(1): 48-55, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33626826

RESUMO

OBJECTIVES: To identify the contents of pills found on an intoxicated patient by ultrahigh-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-QTof).5 To highlight the potential ability that this technique can add to the clinical laboratory. METHODS: Illicit PEZ-like pills purchased from an online vendor, containing unknown substances, were investigated by UHPLC-QTof. Accurate mass and experimental data were obtained. Tentative identifications were subsequently confirmed with commercial standards. RESULTS: Accurate mass data, high-energy mass spectra, elucidation software, and a review of the scientific literature enabled the tentative identification of clonazolam and flubromazolam in the PEZ-like pills. On the basis of these tentative identifications, commercial standards were purchased to confirm the initial findings. On subsequent reinterrogation of the data, flubromazolam was identified in the urine specimen of the patient. CONCLUSIONS: Utilizing high-resolution mass data, 2 novel benzodiazepines were tentatively identified by reinterrogation of a routine analysis for drugs of abuse. Use of UHPLC-QTof in a clinical toxicology laboratory provides additional capabilities to explain and potentially improve treatment of patients presenting to the emergency department with symptoms possibly due to toxic substance ingestion.

10.
Clin Adv Periodontics ; 4(4): 209-215, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32781805

RESUMO

INTRODUCTION: Severe, chronic periodontitis (CP) is typically treated either with scaling and root planing (SRP) or surgical therapy in an effort to gain clinical attachment. The advantage of non-surgical therapy is decreased morbidity to the patient; however, the site typically heals by formation of a long junctional epithelium. The advantage of surgical therapy is access for debridement and the use of bone or bone substitutes in combination with a barrier membrane for epithelial exclusion. Compared with a non-surgical approach, surgical therapy is more invasive, and patient acceptance of treatment is typically more challenging. The use of lasers in dentistry appears to be rapidly increasing, as evidenced by the influx of new lasers into the dental market as well as numerous anecdotal reports of beneficial results with their use. CASE SERIES: This report presents a novel approach to the treatment of severe CP using a carbon dioxide (CO2) laser in combination with SRP. This study presents the findings of 17 patients (nine males and eight females, aged 34 to 71 years; mean age: 54 years) that were compared in a split-mouth design and followed for 3 months. To the best of the authors' knowledge, this is the first reported case series using a CO2 laser for de-epithelialization in combination with SRP for the treatment of CP. CONCLUSION: Sites treated with the CO2 laser tended to show a greater decrease in probing depths, greater amounts of recession, and greater gains in clinical attachment levels, but the results were not statistically significantly better than SRP alone.

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