The significance of procalcitonin test (PCT) in the differential diagnosis of sterile and infectious pancreonecrosis was evaluated. Twenty-four patients with destructive pancreatitis were examined. Plasma procalcitonin concentrations were increased in the patients with infectious pancreonecrosis and correlated with the clinical status of patients evaluated by APACHE II and SOFA scores. The sensitivity and specificity of this test in the diagnosis of infectious pancreonecrosis were 84.4 and 83.3%, respectively, its prognostic significance being as high as 93.1%. Plasma concentrations of procalcitonin in sterile pancreonecrosis were normal or slightly increased. These results indicate that measurement of procalcitonin concentrations is an optimal laboratory test for differential diagnosis of sterile and infectious pancreonecrosis. PCT helps determine the treatment strategy in patients with various forms of destructive pancreatitis.