Prognostication of Mortality in Critically Ill Patients With Severe Infections

Chest. 2015 Sep;148(3):674-682. doi: 10.1378/chest.15-0123.

Abstract

Background: The purpose of this study was to confirm the prognostic value of pancreatic stone protein (PSP) in patients with severe infections requiring ICU management and to develop and validate a model to enhance mortality prediction by combining severity scores with biomarkers.

Methods: We enrolled prospectively patients with severe sepsis or septic shock in mixed tertiary ICUs in Switzerland (derivation cohort) and Brazil (validation cohort). Severity scores (APACHE [Acute Physiology and Chronic Health Evaluation] II or Simplified Acute Physiology Score [SAPS] II) were combined with biomarkers obtained at the time of diagnosis of sepsis, including C-reactive-protein, procalcitonin (PCT), and PSP. Logistic regression models with the lowest prediction errors were selected to predict in-hospital mortality.

Results: Mortality rates of patients with septic shock enrolled in the derivation cohort (103 out of 158) and the validation cohort (53 out of 91) were 37% and 57%, respectively. APACHE II and PSP were significantly higher in dying patients. In the derivation cohort, the models combining either APACHE II, PCT, and PSP (area under the receiver operating characteristic curve [AUC], 0.721; 95% CI, 0.632-0.812) or SAPS II, PCT, and PSP (AUC, 0.710; 95% CI, 0.617-0.802) performed better than each individual biomarker (AUC PCT, 0.534; 95% CI, 0.433-0.636; AUC PSP, 0.665; 95% CI, 0.572-0.758) or severity score (AUC APACHE II, 0.638; 95% CI, 0.543-0.733; AUC SAPS II, 0.598; 95% CI, 0.499-0.698). These models were externally confirmed in the independent validation cohort.

Conclusions: We confirmed the prognostic value of PSP in patients with severe sepsis and septic shock requiring ICU management. A model combining severity scores with PCT and PSP improves mortality prediction in these patients.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomarkers / metabolism*
  • Brazil / epidemiology
  • C-Reactive Protein / metabolism
  • Calcitonin / metabolism
  • Calcitonin Gene-Related Peptide
  • Critical Care*
  • Critical Illness*
  • Female
  • Hospital Mortality
  • Humans
  • Lithostathine / metabolism
  • Male
  • Middle Aged
  • Predictive Value of Tests
  • Prognosis
  • Prospective Studies
  • Protein Precursors / metabolism
  • Sepsis / metabolism
  • Sepsis / mortality*
  • Severity of Illness Index
  • Switzerland / epidemiology

Substances

  • Biomarkers
  • CALCA protein, human
  • Lithostathine
  • Protein Precursors
  • REG1A protein, human
  • Calcitonin
  • C-Reactive Protein
  • Calcitonin Gene-Related Peptide