Abstract:Calprotectin is a potent acute phase reactant with increases of more than 100 fold during inflamed conditions. We measured the diagnostic and prognostic value of serum calprotectin (SC) in septic shock. We enrolled 50 adult shocked patients admitted to intensive care unit. Then, classified into 2 groups; septic group (25) with well-defined septic shock with positive cultures. Non-septic group (25) with negative cultures or no source of sepsis. Blood samples for SC), C-reactive protein (CRP) and white blood cell count (WBCC) in the first 6 hours of ICU admission and re-obtained again on day 3. We observed the weaning of vasopressor and 7-days in ICU mortality. SC measured on day 1 was significantly higher in the septic group than the non-septic group (p<0.001). SC showed a good correlation with weaning of vasopressor (AUC was 0.764; p<0.028), while it showed relative correlation with 7-days in ICU mortality (AUC was 0.752; p<0.057) compared with other markers in the study. SC may aid in rapid identification of septic shock from non-septic shock at a cutoff of 2 µg/dl (sensitivity 92% and specificity 84%). Also the change in SC level may aid in prognostication of septic shock.