Antipyrine metabolism is widely used as an index of the
drug-metabolizing reserve of the liver. It is well known that metabolism of this
drug is impaired in subjects with acute
hepatitis or
cirrhosis, but conflicting data have been reported regarding patients with chronic postinfectious
hepatitis or
liver cancer. We studied conventional liver-function parameters and
antipyrine metabolism (
antipyrine per o.s. 18 mg/kg) in 518 subjects. One hundred and one patients had liver
metastases (various primaries). Based on the number and size of lesions, the hepatic involvement was considered minimal in 47 and massive in 54 (groups B1 and B2, respectively). One hundred and two had
chronic active hepatitis (CAH); 51 patients with histological evidence of
fibrosis/early
cirrhosis and 51 patients were without histological evidence of
fibrosis/early
cirrhosis. Ninety-two had histologically confirmed
cirrhosis (group D), and the remaining 120 had
cirrhosis and
hepatocellular carcinoma (group E). The control group was composed of 103 subjects with healthy livers (group A).
Antipyrine clearance (AP Cl) in CAH patients with
fibrosis (0.246 +/- 0.98 mL/min per kg) was similar to that observed in patients with
cirrhosis (0.223 +/- 0.148 mL/min per kg), and both values were significantly lower than that found in CAH patients without
fibrosis (0.406 +/- 0.159 mL/min per kg, P < 0.01).
Antipyrine clearance in patients with liver
metastases (0.426 +/- 0.174 mL/min per kg) was similar to that of the healthy group (0.489 +/- 0.210 mL/min per kg). Cirrhotics and cirrhotics with
hepatocellular carcinoma (HCC) presented similar degrees of impairment.
Antipyrine clearance was positively correlated with
serum albumin (r2 = 0.10, P = 0.01) and prothrombin time (r2 = 0.129, P < 0.01) in all groups, except those with liver
metastases. In patients with CAH, the presence of
fibrosis/
cirrhosis is associated with impaired
antipyrine metabolism. The lack of impairment in groups with liver
metastases suggests that the functional hepatic reserve is maintained even in the presence of massive neoplastic invasion.