Abramowitz A, Granot E, Tamir I, Deckelbaum R J
J Pediatr Gastroenterol Nutr. 1986 Jan;5(1):130-3. doi: 10.1097/00005176-198601000-00024.
Current requirements for the lactose breath hydrogen test (LBHT) include serial expired air samplings and multiple hydrogen (H2) determinations. One hundred thirty-two consecutive LBHTs were evaluated to determine whether multiple samplings are indeed necessary for detection of lactose malabsorption. Expired air samples were collected at 0, 30, 60, 90, 120, 150, and 180 min following ingestion of lactose. Fifty-five LBHTs were positive for lactose malabsorption. All tests showed abnormally elevated breath H2 concentrations at 120 min. The mean value of the change in parts per million (delta ppm) of H2 at 120 min (51.1 +/- 4.7 SEM) was higher than at any other time point. If only the 120-min samples were examined without subtracting the initial concentrations, four of the 77 negative tests (5.2%) would have been falsely positive. Thus, the values of H2 at 0 and 120 min were sufficient to define lactose malabsorption in all cases. We conclude that just as a single blood sample now suffices for determining xylose malabsorption, so expired air sampling at only 0 and 120 min during the LBHT is a reliable method for detecting lactose malabsorption and diminishes the need for acquiring and analyzing multiple samples.
乳糖呼气氢试验（LBHT）目前的要求包括连续采集呼出气体样本以及多次测定氢气（H2）。对132例连续的LBHT进行评估，以确定检测乳糖吸收不良是否确实需要多次采样。在摄入乳糖后的0、30、60、90、120、150和180分钟采集呼出气体样本。55例LBHT乳糖吸收不良呈阳性。所有测试在120分钟时呼出H2浓度均异常升高。120分钟时H2百万分率变化（δppm）的平均值（51.1±4.7标准误）高于其他任何时间点。如果仅检查120分钟的样本而不减去初始浓度，77例阴性测试中的4例（5.2%）会出现假阳性。因此，0和120分钟时的H2值足以在所有病例中确定乳糖吸收不良。我们得出结论，正如现在单次血液样本就足以确定木糖吸收不良一样，LBHT期间仅在0和120分钟采集呼出气体样本是检测乳糖吸收不良的可靠方法，减少了采集和分析多个样本的必要性。
