Retrospective evaluation and prediction of clearance and toxicity of high dose methotrexate in childhood acute lymphoblastic leukemia patients

To find the predictors of High Dose Methotrexate toxicities in childhood Acute Lymphoblastic Leukemia Patients. This study included 198 Childhood Acute Lymphoblastic Leukemia patients (303 infusions) who were treated with High Dose Methotrexate. Methotrexate levels at different time point were measured by modified enzyme multiplied immunoassay technique assay. The correlation between Methotrexate levels and toxicity was evaluated by Receiver Operating Characteristic curve. When the Methotrexate level at 42 h was lower than 0.76 µmol/L, the sensitivity for predicting thorough clearance at 66 h was 90.78%. When the Methotrexate level at 42 h was higher than1.5 µmol/L, the sensitivity for predicting delayed clearance was 82.17%. When the Methotrexate level at 66 h was higher than 0.5 µmol/L, the sensitivity for predicting Methotrexate toxicity was 89.09%. When the Methotrexate level at 66 h was lower than 0.1 µmol/L, the sensitivity for predicting Methotrexate nontoxicity was 92.73%. The Methotrexate level at 42 h could be predictor for delayed clearance. The Methotrexate level at 66 h could be predictor for toxicity.

Evaluation of Viva-E Drug Testing System / 대한진단검사의학회지

BACKGROUND: The importance and usefulness of therapeutic drug monitoring (TDM) have been emphasized, and analysis of drugs has been increased in clinical laboratories. We evaluated the analytical performance and clinical usefulness of a recently introduced enzyme multiplied immunoassay instrument, Viva-E Drug Testing System (Dade Behring Inc., USA). METHODS: Using patients' samples and quality control material, we evaluated the analytical performance of Viva-E for a total of 11 drugs (cyclosporine, tacrolimus, mycophenolic acid, valproic acid, digoxin, theophylline, carbamazepine, phenytoin, phenobarbital, vancomycin, and gentamicin) with respect to linearity, precision, and correlations with other methods according to CLSI guidelines. Cobas Integra 800 (Roche Diagnostics, Switzerland) and API 4000 LC-MS/MS System (Applied Biosystems, USA) were used to make a comparison. In addition, we analyzed analysis time. RESULTS: Viva-E showed a good linearity (r2 > or = 0.97) for all items. Within-run CVs were within 5% and total CVs were within 10% for all drugs except for tacrolimus and digoxin at low concentrations. The system correlated well with the other methods (r=0.9283-0.9778). The time required for reporting the first sample was 11 min and the analysis time was 1.1 min. CONCLUSIONS: Since Viva-E showed a good analytical performance required for TDM in its linearity, precision, and accuracy with its wide drug menus including cyclosporine, tacrolimus, and mycophenolic acid, stat and random accessing functions, and the consolidation to a single workstation, it could be very useful in the clinical laboratory for various needs.

Aplicação da técnica de imunoensaio enzimático de multiplicação (EMIT) para dosagem de ciclosporina na amostra de sangue absorvido em papel-filtro / Application of the enzymeðmultiplied imunoassay technique (EMIT) to measure ciclosporin in the blood sample absorbed in filter paper

Objetivo: Investigar a aplicabilidade da técnica de imunoensaio enzimático de multiplicação (enzymeðmultiplied immunoassay technique ð EMIT) para dosagem de ciclosporina A (CsA) nas amostras de sangue absorvido em papelðfiltro (STAP). Material e método: Realizaramðse determinações de CsA utilizandoðse técnica de EMIT em 110 amostras; 24 eram de pacientes transplantados cardíacos e 86, dos pacientes transplantados renais. Todos faziam uso da CsA por via oral. Exatamente 12 horas após a tomada da CsA, coletouðse o sangue e prepararamðse as amostras de STAP. As amostras de STAP foram estocadas à temperatura ambiente por períodos de 15 e 30 dias, e as amostras de sangue toral foram estocados a ñ 4ºC, por um tempo inferior a 48 horas, para o teste. Resultados: O coeficiente de correlação entre a técnica que utiliza como amostra sangue total e a amostra de STAP realizada 15 dias após a preparação foi de 0,963, e de 30 dias doi de 0,972 (p < 0,0001). Correlação entre as amostras de STAP de 15 e 30 dias foi de 0,968 (p < 0,0001). A análise de variância nãoðparamétrica de Friedman para os três grupos comparados revelou que ela não foi estatisticamente significante (p < 0,005). Conclusões: A técnica de STAP pode ser utilizada rotineiramente por ser estável, reprodutível e prática. Considerandoðse a dimensão continental de muitos países, este método pode ser bastante útil para a otimização da terapia