Study on parameters of L-[1-^13C]phenylalanine breath test for quantitative assessment of liver function in healthy subjects and patients with hepatitis B virus-related liver disease

1 Introduction Hepatitis B virus-related liver disease is the most common hepatopathy around the world, especially in developing countries like China, which brings more and more increasing healthy and social burden. To measure liver function accurately is critical for moni-toring the progression of liver dysfunction; evaluating the effect of treatment; predicting long term prognosis and risk of surgical interventions and optimal timing of liver transplant. But in clinic, there are few routine…

Study on parameters of L-[1-13C]phenylalanine breath test for quantitative assessment of liver function in healthy subjects and patients with hepatitis B virus-related liver disease

The aims of this study are to investigate the feasibility and validity of the L-1-13C] phenylalanine breath test (13C-PheBT) which has been used to measure hepatocyte functional capacity in hepatitis B virus-related liver disease patients and to propose validity parameters of the test in 12 healthy volunteer, 8 chronic hepatitis and 26 liver cirrhotic patients. 100mg/body nonradiative L-1-13C] phenylalanine (13C-Phe) was administered orally to all subjects.Breath samples were taken before and different intervals within 360 min after administration. The 13CO2/12CO2 enrichment was assessed by isotope ratio mass spectrometer. The parameter percentage 13C excretion rate 13CER, (%13C dose/h) all peaked within 10-30 min after oral 13C-Phe application. The parameters such as maximum value of 13C excretion rate, 13CERmax (% 13C dose/h) (controls: 18.0±3.3; Child A: 11.0±3.8; Child B: 5.0±0.5; Child C:3.6±1.2), 13C excretion rate at 30min, 13CER30 (% dose/h) (controls: 11.9±2.1; Child A: 8.1±0.4; Child B: 6.1±0.9;Child C: 3.2±1.2), 13C cumulative excretion of first 60 min, 13Ccum60 (% 13C dose) (controls: 9.3±1.4; Child A: 6.6±0.7;Child B: 4.1±0.3; Child C: 2.6±0.9) and half time of 13C excretion rate, T1/2 (minutes) (controls: 40.4±4.4; chronic hepatitis: 53.4±4.4; Child A: 59.8±4.5;Child B: 102.0±17.3;Child C: 212.1±87.9) were effective indexes which could be employed to stage hepatocyte impairment and liver functional reserve of advanced HBV-related cirrhotic patients (i.e. healthy subjects, Child A, B, C);T1/2 was also useful for distinguishing mild HBV-related liver injure.