Incidence and predictive risk factors of neutropenic sepsis in post-chemotherapy febrile patients in emergency department: A single-center retrospective longitudinal study

Abstract

Introduction: Neutropenic sepsis is an emergency sequela in post-chemotherapy fever. Its definition comprises of spectrums of diseases with variable quoted mortality. This study aims to evaluate the incidence of “modified” neutropenic sepsis, with a more stringent definition employed. Predictive risk factors toward occurrence of “modified” neutropenic sepsis among Chinese patients would also be explored. Methods: A single-center retrospective longitudinal study was conducted in a medium-sized regional hospital in Hong Kong. All patients with diagnoses of post-chemotherapy fever fulfilling the inclusion and exclusion criteria were recruited. Baseline characteristics and outcome variables of each case subject were collected. Six potential predictive risk factors were chosen for further analysis. Case subjects were followed up for the inpatient progress and outcomes. Relative risks of each risk factor to “modified” neutropenic sepsis were calculated. Results: A total of 135 case subjects were recruited. Five developed “modified” neutropenic sepsis, that is, incidence 3.70% (95% confidence interval = 1.59%–8.38%). Only background hematological malignancy was found to be significantly associated with the outcome of “modified” neutropenic sepsis (Relative Risk [RR] 13.2, 95% confidence interval = 1.56–115.70, p = 0.010), with an incidence of 12.9% (95% confidence interval = 5.14%–28.85%). Hematological malignancy was also found to be significantly associated with lower median absolute neutrophil counts (0.95 × 109/L vs 2.3 × 109/L, p = 0.005) and longer median hospital stay (8 days vs 6 days, p < 0.001). Conclusion: Incidence of “modified” neutropenic sepsis is low. Hematological malignancy is associated with significantly higher rate of “modified” neutropenic sepsis.