Determination of Serum Carbohydrate-Deficient Transferrin (CDT) by the Nephelometric N Latex CDT Assay in Japanese Habitual Drinkers and Patients with Non-Alcoholic Liver Diseases

Abstract

Background: Excessive alcohol consumption is a health risk that can lead to a variety of medical and social problems. Carbohydrate Deficient Transferrin (CDT) is now widely used for detection of chronic alcohol abuse and monitoring sobriety in alcoholics. We assessed the diagnostic performance of the direct immunoassay for %CDT (N Latex CDT) in Japanese habitual drinkers at their annual medical check-up. We also tested whether this direct assay is influenced by the presence of non-alcoholic liver disease including non-alcoholic steatohepatitis and HCVrelated hepatocellular carcinoma. Methods: We performed the N Latex CDT assay using a Siemens BN-II nephelometric analyzer to measure CDT concentration. The reference intervals of %CDT and gamma glutamyl transferase (GGT) activities were obtained based on their measurements in 160 apparently healthy nondrinkers. Habitual drinkers were divided into light drinkers (less than 40g ethanol/day) and heavy drinkers (more than 60g ethanol/day) Furthermore, %CDT levels in a total of 184 patients with non-alcoholic chronic liver diseases including Hepatitis C Virus (HCV) related liver cirrhosis, Non-Alcoholic Steatohepatitis (NASH) were determined. Results: In the heavy drinkers, the positive rates of %CDT and GGT were 58.3% and 41.7%, respectively. The combination assay of %CDT and GGT resulted in 75% sensitivity and 95% specificity. It was notable that 57% of GGT non-responders were detected by CDT measurements. The mean serum level of %CDT was not influenced by the presence of NASH, but was increased in patients with moderate-severe HCV-related liver cirrhosis. The %CDT levels were also high in patients with hepatocellular carcinoma with liver cirrhosis, but were not related to their tumor stages. Conclusions:The %CDT determined by automated N Latex CDT may be useful biomarker complementary to GGT to detect excessive habitual drinkers in Japan. However, caution should be taken to interpret the results in advanced non-alcoholic liver cirrhosis.