BACKGROUND: Dihydropyrimidine dehydrogenase (DPD) activity determination in peripheral blood mononuclear cells of DPD deficient patients was hitherto inaccurate due to hemoglobin (Hb) contamination. We developed an improved method for accurate measurement of DPD activity in patients. RESULTS: DPD activity was determined by HPLC with online radioisotope detection using liquid scintillation counting. Hb was determined spectrophotometrically. Method accuracy and precision were significantly improved by using cumulative area of all peaks as IS. Peripheral blood mononuclear cell lysates from DPD deficient patients were highly contaminated with on average 23.3% (range 2.7-51%) of Hb resulting in up to twofold underestimated DPD activity. DPD activities were corrected for Hb contamination. The method was validated and showed good long-term sample stability. CONCLUSION: This method has increased specificity allowing accurate identification of DPD deficient patients.
BACKGROUND:Dihydropyrimidine dehydrogenase (DPD) activity determination in peripheral blood mononuclear cells of DPD deficientpatients was hitherto inaccurate due to hemoglobin (Hb) contamination. We developed an improved method for accurate measurement of DPD activity in patients. RESULTS:DPD activity was determined by HPLC with online radioisotope detection using liquid scintillation counting. Hb was determined spectrophotometrically. Method accuracy and precision were significantly improved by using cumulative area of all peaks as IS. Peripheral blood mononuclear cell lysates from DPD deficientpatients were highly contaminated with on average 23.3% (range 2.7-51%) of Hb resulting in up to twofold underestimated DPD activity. DPD activities were corrected for Hb contamination. The method was validated and showed good long-term sample stability. CONCLUSION: This method has increased specificity allowing accurate identification of DPD deficientpatients.
Authors: Bart A W Jacobs; Maarten J Deenen; Dick Pluim; J G Coen van Hasselt; Martin D Krähenbühl; Robin M J M van Geel; Niels de Vries; Hilde Rosing; Didier Meulendijks; Artur M Burylo; Annemieke Cats; Jos H Beijnen; Alwin D R Huitema; Jan H M Schellens Journal: Br J Clin Pharmacol Date: 2016-06-03 Impact factor: 4.335
Authors: Bart A W Jacobs; Nikol Snoeren; Morsal Samim; Hilde Rosing; Niels de Vries; Maarten J Deenen; Jos H Beijnen; Jan H M Schellens; Miriam Koopman; Richard van Hillegersberg Journal: Eur J Clin Pharmacol Date: 2018-02-11 Impact factor: 2.953
Authors: Jeroen Roosendaal; Bart A W Jacobs; Dick Pluim; Hilde Rosing; Niels de Vries; Erik van Werkhoven; Bastiaan Nuijen; Jos H Beijnen; Alwin D R Huitema; Jan H M Schellens; Serena Marchetti Journal: Pharm Res Date: 2020-05-07 Impact factor: 4.200
Authors: Linda M Henricks; Bart A W Jacobs; Didier Meulendijks; Dick Pluim; Daan van den Broek; Niels de Vries; Hilde Rosing; Jos H Beijnen; Alwin D R Huitema; Henk-Jan Guchelaar; Annemieke Cats; Jan H M Schellens Journal: Br J Clin Pharmacol Date: 2018-09-25 Impact factor: 4.335