Serum copper and zinc levels in Thai patients with various diseases

This study was conducted to evaluate the possible alteration of serum Cu and Zn levels in 118 medical inpatients (53 women and 65 men) in Ramathibodi Hospital. Patients were classified according to their main clinical diseases: pulmonary (n = 12), renal (14), infectious (30), malignant (9), cardiovascular (22), GI & hepatic (13) and hematological (18) diseases. Significantly increased serum Cu concentrations were found in patients with pulmonary, malignant, cardiovascular and infectious diseases; moreover, 75, 75, 50 and 37 per cent of these diseases, respectively, had serum levels greater than the normal mean + 2SD (23.6 mumol/L). Besides, 5 per cent of patients (3 in renal, 1 in infectious and 2 in GI & hepatic diseases) had low serum Cu levels suggestive of Cu depletion. By contrast, significantly decreased serum Zn concentrations were found in patients with GI & hepatic, infectious, renal, cardiovascular and malignant diseases. Serum Zn levels below the normal mean - 2SD (8.1 mumol/L) were presented in 46, 37, 29, 23 and 22 per cent of cases, respectively. It was found that serum Cu/Zn ratio in our patients not only with cancer but also with other diseases were statistically significant from the normal group. Hence, the use of serum Cu/Zn ratios as markers for the diagnosis of cancer or for staging tumors must be interpreted cautiously.