Could quantitative liver function tests gain wide acceptance among hepatologists?

Table 1 Frequently used QLFTs in patients with liver cirrhosis, chronic viral hepatitis and non-alcoholic liver disease

Type	Methods/drawbacks
GEC	Intravenous administration of galactose; blood samples at 5, 25 and 45 min; urine collected for 5 h
ICG	Measurement of liver plasma flow; injection of ICG must be performed quickly; blood samples at 3, 6 and 49 min
MEGX	Blood samples at 15 and 30 min after i.v. lidocaine administration; allergy to anesthetics
ABT	Resting period of at least 30 min before the breath test that should be repeated three times at 10-min intervals
13C-C breath test	Subjects ingested 2 mg/kg of [3-methyl-13C]-caffeine sitting quietly for 15 min before and throughout the test; breath samples were collected immediately prior to, and 60 min after, caffeine ingestion
13C-M breath test	Measurement of breathed CO2 by laser-based technology
SCl	Measurement of liver plasma flow. Sorbitol (500 g/L) was administered via a perfusor at 7.5 mL/h. Serum and urinary concentrations of sorbitol were determined at the beginning of the perfusion and after reaching steady-state
TOSCA	Unique sample of saliva to be collected in the morning; rare complaiance to drinks containing caffeine by some patients
LURs	Volumetric information as well as functional assessment; expensive
MRI	Expensive; to be validated

QLFTs: Quantitative liver function tests; GEC: Galactose elimination capacity; ICG: Indocyanine green; MEGX: Monoethylglycinexylidide; ABT: Aminopyrine breath test; MRI: Magnetic resonance imaging; LURs: Liver uptake ratios.