RESUMO
BACKGROUND: Concerning the link between copper excess and the pathogenesis of chronic liver diseases, its retention is reckoned to develop as a complication of cholestasis. Recently, it has been found that cholestatic liver injury involves largely inflammatory cell-mediated liver cell necrosis, with consequent reduced hepatic mass, more than occurring through direct bile acid-induced apoptosis. On the other hand, interference with protein synthesis could be expected to result, ending in an altered ability of the liver to retain copper. Little is known about the association between serum copper and clotting factors in cirrhotics. We aimed at studying a possible relationship between increased levels of copper and an aspect of the haemostatic process in liver cirrhosis patients, assessing an index of protein synthesis (albumin) and parameters of protein synthesis/coagulation/fibrinolysis, such as prothrombin time (PT), antithrombin (AT) III and fibrinogen. METHODS: Records from 85 patients suffering from liver cirrhosis of various aetiology and different severity were retrospectively examined. Serum concentrations of copper were determined by atomic absorption spectrophotometer. An index of protein synthesis, such as albumin and parameters of both synthesis and coagulation/hypercoagulation such as PT %, AT III%, levels of fibrinogen were taken into account to study possible correlations to serum copper. The severity of cirrhosis was evaluated by the Child-Pugh (C-P) classification. The relationship among variables were studied by linear regression. RESULTS: Copper levels of patients suffering from liver cirrhosis were increased respect to those of controls, 102.7+/-28.7 versus 80.4+/-19.5 mcg/dL, (P = .0009), independently from disease severity, and were positively predicted by PT% (P = 0. 017), fibrinogen (P = 0.007) and AT III% (P = 0.000), at linear regression. Among the previous parameters, to which serum albumin was added, the unique predictor of copper levels was AT III%, at multiple regression (P = 0. 010); AT III% was negatively predicted by the C-P classification (P = 0.000); copper levels, adjusted for C-P classification, were predicted by AT III% (P = 0.020) and fibrinogen concentrations, but not by PT% (P = 0.09). CONCLUSION: The copper concentration is reckoned as responsible for production of the hydroxyl radicals. On the basis that oxidants may enhance the activity of the extrinsic coagulation cascade, ultimately leading to thrombin formation, via their combined effects on stimulation of tissue factor activity and inhibition of fibrinolytic pathways, the positive relationship of copper to coagulation/hypercoagulation parameters (mainly AT III) in our research could find a plausible interpretation.