Rapid kinetic rate assay of the serum alpha-L-fucosidase in patients with hepatocellular carcinoma by using a novel substrate.

Background: Developing kinetic rate assay kit for alpha-L-fucosidase (AFU) by using a novel substrate 2-chloro-4-nitrophenyl-alpha-L-fucopyranoside (CNPF) and clinical implication in the diagnosis of hepatocellular carcinoma (HCC).

Methods: We have evaluated the new kinetic rate assay kit using a novel substrate for serum AFU employing Hitachi 7170 automated analyzer. The reaction was carried out at 37 degrees C, monitoring the wavelength at 405 nm. Serum samples from 884 Chinese subjects including 518 healthy adults and 366 patients were determined using this kit.

Results: The linearity was observed up to 300 U/L. The intra-assay precision (n=10) was S.D. 0.47; CV 2.6 (AFU activity, 17.8 U/L), S.D. 0.31; CV 0.79% (AFU activity, 39.71 U/L) and S.D. 0.79; CV 0.77% (AFU activity, 102 U/L). The day-to-day assay precision (n=10) was 3.96% (AFU activity: 41.1 U/L). There was no significant interference of various substances such as ascorbic acid (6 g/L), hemoglobin (220 mg/L) and bilirubin (200 mg/L). Serum AFU value for healthy adults was estimated at 22.8+/-7.1 U/L. No significant difference was found between male and female groups (p>0.05). The mean value of serum AFU activity in patients with HCC was significantly higher than in patients with cirrhosis, chronic hepatitis, other malignant neoplasm, other diseases and control subjects. No significant differences were found between controls and patients with cirrhosis, chronic hepatitis, patients, other malignant neoplasm and other diseases. The sensitivity and specificity was 81.5% and 85.4%, respectively.

Conclusions: Serum alpha-L-fucosidase is a useful maker in the diagnosis of HCC. The assay had high sensitivity and specificity. The procedure determined is simple, rapid, convenient, and can be adapted to automated clinical analyzers for use in large-scale screening for early diagnosis of HCC.