Shippee R L, Johnson A A, Cioffi W G, Lasko J, LeVoyer T E, Jordan B S
U.S. Army Institute of Surgical Research, Fort Sam Houston, TX 78234-5012.
Clin Chem. 1992 Mar;38(3):343-5.
Ratios of lactulose/mannitol excretion in urine have been used to assess the extent of intestinal permeability in various disease and trauma conditions. Reported studies have used this technique to correlate altered gastrointestinal mucosal permeability to translocation of bacteria and endotoxin, leading to occult sepsis in burn patients. Enzymatic methods of analysis for urine concentrations of mannitol and lactulose were used in these studies. We have found that urine from patients with severe burns frequently contains compounds that interfere with the enzymatic methods. We describe using gas-liquid chromatography to determine mannitol and lactulose simultaneously in the urine of burn patients. To avoid the multiple peaks for the anomeric forms of the reducing sugars during precolumn trimethylsilyl derivatization, we converted the sugars to oximes before the silylation step. The method gave good recoveries of mannitol and lactulose added to burn patients' urine samples. Unlike the enzymatic methods, gas-liquid chromatography eliminates the effect of interfering compounds and allows for the simultaneous determination of both sugars in urine samples.
尿中乳果糖/甘露醇排泄率已被用于评估各种疾病和创伤情况下肠道通透性的程度。已报道的研究使用该技术将胃肠道黏膜通透性改变与细菌和内毒素易位相关联，从而导致烧伤患者发生隐匿性脓毒症。这些研究采用酶法分析尿中甘露醇和乳果糖的浓度。我们发现，严重烧伤患者的尿液中常常含有干扰酶法的化合物。我们描述了使用气液色谱法同时测定烧伤患者尿液中的甘露醇和乳果糖。为避免在柱前三甲基硅烷基衍生化过程中还原糖异头物形式出现多个峰，我们在硅烷化步骤之前将糖转化为肟。该方法对添加到烧伤患者尿液样本中的甘露醇和乳果糖具有良好的回收率。与酶法不同，气液色谱法消除了干扰化合物的影响，并允许同时测定尿液样本中的两种糖。
