C-reactive protein in critically ill cancer patients with sepsis: influence of neutropenia

Introduction: Several biomarkers have been studied in febrile neutropenia. Our aim was to assess C-reactive protein (CRP) concentration in septic critically ill cancer patients and to compare those with and without neutropenia. Methods: A secondary analysis of a matched case-control study conducted at an oncologic medical-surgical intensive care unit (ICU) was performed, segregating patients with severe sepsis/septic shock. The impact of neutropenia on CRP concentrations at admission and during the first week of ICU stay was assessed. Results: A total of 154 critically ill septic cancer patients, 86 with neutropenia and 68 without, were included in the present study. At ICU admission, the CRP concentration of neutropenic patients was significantly higher than in non-neutropenic patients, 25.9 +/- 11.2 mg/dL vs. 19.7 +/- 11.4 mg/dL (P = 0.009). Among neutropenic patients, CRP concentrations at ICU admission were not influenced by the severity of neutropenia (< 100/mm(3) vs. >= 100/mm(3) neutrophils), 25.1 +/- 11.6 mg/dL vs. 26.9 +/- 10.9 mg/dL (P = 0.527). Time dependent analysis of CRP from Day 1 to Day 7 of antibiotic therapy showed an almost parallel decrease in both groups (P = 0.335), though CRP of neutropenic patients was, on average, always higher in comparison to that of non-neutropenic patients. Conclusions: In septic critically ill cancer patients CRP concentrations are more elevated in those with neutropenia. However, the CRP course seems to be independent from the presence or absence of neutropenia.