Trace elements analysis of ascitic fluid in benign and malignant diseases

Objectives: To evaluate differences in ascitic fluid trace element concentrations which might be useful in discrimination between benign and malignant ascites. Design and Methods: The concentrations of copper, zinc, magnesium and iron in ascitic fluid and venous blood in 17 patients were investigated. The relationship between these trace elements and type of disease were examined. Investigations were carried out in a group of 5 males and 5 females aged 54 to 77 yr who had cirrhosis ascites and in a group of 7 females aged 41 to 76 yr with ascites due to gynecologic neoplasms. Results: The mean ascitic fluid and serum concentrations of copper were significantly higher in neoplastic diseases compared to benign disease states (118,43 vs. 97,50, 91,14 vs. 26.90) (p< 0,05 and p< 0,01 respectively). The zinc levels in ascitic fluid and serum were significantly different between the groups (p< 0,01). Neoplastic patients had significantly higher ascitic fluid magnesium levels than the benign disease group (2,17 vs. 1,55, p< 0,001). The serum levels of iron were significantly lower in the neoplastic diseases group (92, 28 vs. 255, p< 0, 01). In benign diseases the concentration of zinc in ascitic fluid correlated positively with ascitic fluid copper concentrations. The concentrations of zinc and iron in malignant ascites correlate positively with the magnesium concentrations. Statistically significant negative correlations were found between ascites zinc and magnesium and magnesium and copper in cirrhotic patients and magnesium and copper in malignant diseases. Conclusions: The results showed that zinc, magnesium and iron levels were significantly different between cirrhotic and neoplastic illness. Analysis of serum and ascitic fluid trace element composition may be helpful in identifying and distinguishing the malignant and nonmalignant ascites and provides useful information on processes regulating passage of blood components into the peritoneal cavity.