*Department of Biochemistry, Faculty of Medicine Siriraj Hospital, Mahidol University,Bangkok 10700, Thailand.
Wilson’s disease is a rare inherited disease with an incidence of 1:50,000 to 1:1,000,0001. The mode of transmission of this disease is an autosomal recessive. The defects of the disease involve both an impairment in biliary copper excretion and a decreased incorporation of free copper into ceruloplasmin due to a low level or abnormal function of this alpha 2-globulin. The toxic accumulation of copper damages many tissues especially basal ganglia of brain and liver. The diagnosis of this disease is made from the family history, signs and symptoms especially from the damaged organs, the detection of Kayser-Fleischer ring, a copper deposit in cornea and the decreased level of serum ceruloplasmin below 20 mg/ml which is normally found in more than 95% of cases. In this study, we analysed the levels of serum ceruloplasmin from 23 cases of Wilson’s disease admitted in Siriraj Hospital from 1989-1998. The average value, (X+1 SD), of 1.38+3.55 mg/ml was significantly lower when compared with the value of 20.82+3.63 mg/ml from 46 normal controls. The cut off level of ceruloplasmin for Wilson’s disease in Thai patients from this study was estimated to be 13 mg/ml which is lower than the level of 20 mg/ml in standard textbook. Twenty two out of 23 cases of Wilson’s disease (95.65%) had serum ceruloplasmin levels less than 13 mg/ml while 1 out of 23 cases (4.35%) had normal level. The data strongly supported the usefulness of serum cerloplasmin analysis in the diagnosis of Wilson’s disease.