Wong Jonathan, Jeraj Hassan, Vilar Enric, Viljoen Adie, Farrington Ken
Department of Renal Medicine, Lister Hospital, Hertfordshire, UK Department of Postgraduate Medicine, University of Hertfordshire, Hertfordshire, UK.
Quality Control Department, Lister Hospital, Hertfordshire, UK.
J Clin Pathol. 2015 Jan;68(1):73-8. doi: 10.1136/jclinpath-2014-202622. Epub 2014 Nov 6.
Endotoxin detection assays are not validated for use in end-stage kidney disease (ESKD). We investigated the accuracy and precision of the kinetic turbidimetric Limulus amoebocyte lysate (LAL) assay to detect endotoxin in plasma from patients with ESKD. Optimisation of endotoxin recovery from plasma using the detergent Tween 80 was also explored.
Plasma samples from 7 patients with ESKD and 7 healthy subjects were spiked with different concentrations of endotoxin. Repeated measurements for endotoxin at each level of spike were performed to assess the accuracy and precision of spike recovery. Endotoxin recovery in plasma samples diluted in Tween 80 and water was compared.
Mean endotoxin spike recovery was 111.6% and 125.2% in ESKD and healthy subjects, respectively. There was no statistical difference in spike recovery between ESKD and healthy plasma. Precision of the LAL assay in plasma spiked with low (0.05 EU/mL) and high (0.5 EU/mL) concentration of endotoxin spikes was 24.1% and 8.9%, respectively. The use of Tween 80 as a diluent for plasma significantly improved spike recovery in ESKD plasma (100.1% vs 70.4%, p<0.001).
The kinetic LAL turbidimetric assay is a valid tool for the detection of blood endotoxin in patients with ESKD, although in blood specimens with low-level endotoxemia (≤0.05 EU/mL) the assay may be less accurate and precise. Tween 80 can be used as a diluent to optimise recovery of endotoxin in ESKD plasma.
内毒素检测方法尚未在终末期肾病（ESKD）中得到验证。我们研究了动态比浊法鲎试剂检测ESKD患者血浆中内毒素的准确性和精密度。同时还探索了使用去污剂吐温80优化血浆中内毒素回收率的方法。
向7例ESKD患者和7例健康受试者的血浆样本中加入不同浓度的内毒素。对每个加样水平的内毒素进行重复测量，以评估加样回收率的准确性和精密度。比较在吐温80和水中稀释的血浆样本中的内毒素回收率。
ESKD患者和健康受试者的平均内毒素加样回收率分别为111.6%和125.2%。ESKD患者和健康血浆之间的加样回收率无统计学差异。在加入低浓度（0.05 EU/mL）和高浓度（0.5 EU/mL）内毒素加样的血浆中，鲎试剂检测法的精密度分别为24.1%和8.9%。使用吐温80作为血浆稀释剂可显著提高ESKD血浆中的加样回收率（100.1%对70.4%，p<0.001）。
动态比浊法鲎试剂检测法是检测ESKD患者血液内毒素的有效工具，尽管在低水平内毒素血症（≤0.05 EU/mL）的血液标本中，该检测法的准确性和精密度可能较低。吐温80可作为稀释剂来优化ESKD血浆中内毒素的回收率。
