Version 7.4.4.1 for windows

Statistical analyses were performed using SPSS for Windows 15.0 (SPSS Inc., Chicago, IL, USA), MedCalc version 7.4.4.1 for Windows (MedCalc Software) and Statistica 6.0 programme (Stat Soft, Inc., USA). The descriptive statistics are presented by their main characteristics: m -mean value, Me -median, σ -standard deviation, and 25%÷75% -quartiles. Testing of the hypothesis that the distribution of samples was not normal was made by Kolmogorov-Smirnov and Shapiro-Wilk tests. Non-parametric analytical methods were used: Spearman correlation coefficient (r), comparison of two independent groups by Mann-Whitney U test, comparison of several independent groups using the Kruskal-Wallis H-test and a median test with a minimum level of statistical significance of p < 0.05. Parametric analytical methods (Newman-Keuls and Duncan) were also used to compare more than two independent samples. Comparisons between groups were performed using the Chi-square (χ 2 ) test for categorical variables. Areas under receiver operating characteristic curve (AUC) were used to evaluate the ability of IL-6, IL-8, IL-10, TNF-α, CRP, CR and SOFA score to discriminate survivors from non-survivors, as well as patients with SS-AP from patients without SS-AP. AUC were pairwise compared. Statistical significance was defined as a p-value < 0.05.