Macdougall L G, McElligott S E, Ross E, Greeff M C, Poole J E
Department of Paediatrics, University of Witwatersrand, Johannesburg, South Africa.
Ther Drug Monit. 1992 Oct;14(5):371-5. doi: 10.1097/00007691-199210000-00005.
A method for the measurement of 6-mercaptopurine (6MP) in urine using high-performance liquid chromatography is described. Urinary excretion of 6MP was measured in 46 children with acute lymphoblastic leukemia. The proportion of unchanged drug excreted after oral dosage in the morning was greater than after an evening dose (5.6 +/- 3.3% vs. 3.3 +/- 2.4%). Possible reasons for the discrepancy are discussed. In all children receiving 6MP in the morning, the drug was detected in urine at 2 and 4 h after ingestion. At 6 h, 6MP was still detectable in 77% of patients, at 8 h in 54%, at 10 h in 12%, and at 12 h in 8%. The reliability of urinary 6MP determination as a measure of drug compliance was assessed in 39 children accustomed to receiving their medication in the evening. 6MP was detected in 81% of first morning urine samples, indicating compliance with medication the preceding evening. The absence of 6MP in first morning urine samples did not necessarily indicate poor compliance because of the variability in 6MP excretion and unpredictable pattern of night voiding in children. The method was therefore a reliable measure of good short-term compliance. It also directed attention toward possible noncompliance in children with negative samples.
描述了一种使用高效液相色谱法测量尿液中6-巯基嘌呤（6MP）的方法。对46例急性淋巴细胞白血病患儿的6MP尿排泄情况进行了测量。早晨口服剂量后排泄的未变化药物比例高于晚上服药后（5.6±3.3%对3.3±2.4%）。讨论了差异的可能原因。在所有早晨接受6MP治疗的患儿中，服药后2小时和4小时在尿液中检测到该药物。6小时时，77%的患者尿液中仍可检测到6MP，8小时时为54%，10小时时为12%，12小时时为8%。在39名习惯晚上服药的患儿中评估了尿6MP测定作为药物依从性衡量指标的可靠性。81%的首次晨尿样本中检测到6MP，表明前一晚服药依从。首次晨尿样本中未检测到6MP不一定表明依从性差，因为6MP排泄存在变异性且儿童夜间排尿模式不可预测。因此，该方法是良好短期依从性的可靠衡量指标。它还使人们关注样本为阴性的儿童可能存在的不依从情况。
