Pfaffenbach B, Götze O, Szymanski C, Hagemann D, Adamek R J
Medizinische Klinik 1, Städtisches Klinikum, Solingen.
Dtsch Med Wochenschr. 1998 Dec 4;123(49):1467-71. doi: 10.1055/s-2007-1024202.
Cytochrome-P450-dependent liver function can be measured with the 13C-methacetin breath test (MBT). This has heretofore been done with the use of a mass-spectrometer. This study was undertaken to evaluate the MBT (NDIRS) done with the isotope-selective nondispersive infrared spectrometer.
20 healthy volunteers (ten women, ten men, aged 22-76 years) and 16 patients (ten women, six men, aged 48-71 years) with histologically confirmed liver cirrhosis (Child-Pugh stage A [n = 7], B [n = 5] or C [n = 4]) were given 13C-methacetin in 100 ml of tea after a 12-hour fasting period. Breath tests were performed before the test drink and 5, 10, 15, 20, 30, 40, 50, 60, 80, 100, 120, 150 and 180 min thereafter. The ratio of 13C to 12C was determined, as delta (/1000), and from it the maximal percentage rate (PDRmax) calculated, as well as the cumulative rate (cPDRmax) after 30, 60, 120 and 180 min (Median and 5th and 95th percentiles).
For patients with liver cirrhosis there were significantly lower values for cPDRmax and cPDR after 30, 60, 120 and 180 min than in the healthy subjects (P < 0.002): PDR [%]/h: 3.9 (0.7-15.9) vs. 36.5 (23.1-50.0); cDPR 30 min [%]: 1.1 (-0.2-6.0) vs. 12.4 (7.6-17.1); cDPR 3 h [%]: 9.8 (-2.3-27.5) vs. 36.0 (29.9-45.1). There were significant differences among the patients, depending on their Child-Pugh staging.
The MBT with the cost-effective NDIRS can reliably and noninvasively distinguish between healthy subjects and patients with liver cirrhosis. The test is therefore suitable for the quantitative analysis of liver functions.
细胞色素P450依赖的肝功能可用13C - 美沙西汀呼气试验（MBT）来检测。此前一直是使用质谱仪进行此项检测。本研究旨在评估使用同位素选择性非分散红外光谱仪进行的MBT（NDIRS）。
20名健康志愿者（10名女性，10名男性，年龄22 - 76岁）以及16名经组织学确诊为肝硬化的患者（10名女性，6名男性，年龄48 - 71岁，Child - Pugh A期[n = 7]、B期[n = 5]或C期[n = 4]）在禁食12小时后，通过100毫升茶服用13C - 美沙西汀。在饮用测试饮品前以及之后的5、10、15、20、30、40、50、60、80、100、120、150和180分钟进行呼气试验。测定13C与12C的比率，以δ（/1000）表示，并据此计算最大百分比速率（PDRmax）以及30、60、120和180分钟后的累积速率（cPDRmax）（中位数以及第5和第95百分位数）。
肝硬化患者在30、60、120和180分钟后的cPDRmax和cPDR值显著低于健康受试者（P < 0.002）：PDR[％]/小时：3.9（0.7 - 15.9）对36.5（23.1 - 50.0）；30分钟时的cDPR[％]：1.1（ - 0.2 - 6.0）对12.4（7.6 - 17.1）；三小时时的cDPR[％]：9.8（ - 2.3 - 27.5）对36.0（29.9 - 45.1）。根据Child - Pugh分期，患者之间存在显著差异。
使用性价比高的NDIRS进行的MBT能够可靠且无创地区分健康受试者和肝硬化患者。因此，该测试适用于肝功能的定量分析。
