Influence of azathioprine on hepatic reserve in chronic active liver disease.

The kinetics of hepatic indocyanine green (ICG) uptake have been analysed in 14 patients with chronic active liver disease. The removal of incremental, submaximal ICG doses were compatible with Michaelis-Menten kinetics in approximately 80% of studies in patients allowing the calculation of the maximal rate of removal (Rmax) and the Michaelis constant (Km). Neither of these variables correlated with other laboratory indices of liver function. Although determinations of Rmax before and after a two-weeks trial of azathioprine therapy were not significantly different, in two patients Rmax was markedly reduced by treatment. It is concluded that azathioprine over the short term does not improve the liver's reserve for ICG removal; in fact, in isolated cases this drug may be detrimental.