Introduction The German Diabetes Association recommends using sampling tubes with citrate and fluoride additives to diagnose diabetes by oral glucose tolerance test to inhibit glycolysis. The effect of different tubes on measurement results was assessed.

Materials and Methods In a first study, an oral glucose tolerance test was performed on 41 participants without anamnestically known diabetes. Venous blood was sampled in two different tubes with citrate/fluoride additives from different manufacturers and one with only lithium-heparin additive. A second study with 42 participants was performed to verify the initial results with an adapted design, in which a third tube with citrate buffer was used, and glucose measurements were performed on two additional devices of another analyser model. Samples were centrifuged either immediately (<5 min incubation time) or after 20 min or 4 h. All glucose measurements were performed in plasma. Glucose concentrations in lithium-heparin tubes with<5 min incubation time served as baseline concentrations.

Results In the first study, glucose concentrations in one of the citrate/fluoride tubes were similar to the baseline. In the other citrate/fluoride tube, markedly lower concentrations (approximately − 5 mg/dL (− 0.28 mmol/L)) were measured. This was reproduced in the verification study for the same analyser, but not with the other analyser model. Lithium-heparin tubes centrifuged after 20 and 240 min showed systematically lower glucose concentrations.

Conclusions The results confirm that glycolysis can be effectively inhibited in citrate/fluoride-containing sampling tubes. However, glucose measurement results of one analyser showed a relevant negative bias in tubes containing liquid citrate buffer.

简介德国糖尿病协会建议使用含有柠檬酸盐和氟化物添加剂的采样管，通过口服葡萄糖耐量试验抑制糖酵解来诊断糖尿病。评估不同管对测量结果的影响。

材料和方法在第一项研究中，对 41 名无糖尿病史的参与者进行了口服葡萄糖耐量测试。在两支不同的试管中采集静脉血样本，其中两支试管含有来自不同制造商的柠檬酸盐/氟化物添加剂，另一支试管仅含有肝素锂添加剂。第二项研究有 42 名参与者参与，以验证采用适应性设计的初始结果，其中使用了第三根装有柠檬酸盐缓冲液的试管，并在另一种分析仪型号的另外两个设备上进行了葡萄糖测量。样品立即离心（<5 分钟孵育时间）或 20 分钟或 4 小时后离心。所有葡萄糖测量均在血浆中进行。孵育时间<5分钟的肝素锂管中的葡萄糖浓度作为基线浓度。

结果在第一项研究中，其中一个柠檬酸盐/氟化物管中的葡萄糖浓度与基线相似。在另一个柠檬酸盐/氟化物管中，测量到明显较低的浓度（大约 - 5 mg/dL (- 0.28 mmol/L)）。这在同一分析仪的验证研究中得到了重现，但其他分析仪型号却没有重现。 20 和 240 分钟后离心的肝素锂管显示出系统性较低的葡萄糖浓度。

结论结果证实，在含柠檬酸盐/氟化物的采样管中可以有效抑制糖酵解。然而，一台分析仪的葡萄糖测量结果在含有液体柠檬酸盐缓冲液的试管中显示出相关的负偏差。