The association between agranulocytosis and 30-day mortality in patients with hematological disorders and bloodstream infections: A retrospective cohort study

Agranulocytosis and bloodstream infections (BSIs) are common complications in patients with hematological disorders and they are life-threatening. This study aims to explore the association between agranulocytosis and 30-day mortality in individuals with hematological disorders and BSIs. In this retrospective cohort study, neutrophil levels were measured in patients presenting with fever and diagnosed with a hematological disorder at Tongde Hospital of Zhejiang Province between March 2018 and August 2023. The primary outcome was all-cause 30-day mortality. Multivariate Cox proportional hazard models were used to identify factors associated with survival among patients with hematological disorders and BSIs. Survival outcomes between agranulocytosis (neutrophils < 0.5 × 109/L) and non-agranulocytosis (neutrophils ≥ 0.5 × 109/L) were compared via the Kaplan-Meier method. Subgroup analyses were conducted, stratified by relevant effect covariates. The study included 113 (56.8%) males and 86 (43.2%) females, with a median age of 57.4 years. The overall 30-day mortality rate was 33.7% (67/199), with mortality rate of 26.1% (24/92) in the non-agranulocytosis group and 40.2% (43/107) in the agranulocytosis group (P = .036). After adjusting for potential confounders, a significant association between a 2% increase in the 30-day mortality rate and a 0.1 × 109/L decrease in neutrophil levels was observed (95% confidence interval [CI]: 1.00-1.03, P = .006). Furthermore, agranulocytosis was associated with a 95% increase in 30-day mortality compared to non-agranulocytosis (95% CI: 1.10-3.46, P = .023). The findings from the subgroup and stratified analyses were consistent and robust. Agranulocytosis was positively associated with all-cause 30-day mortality in patients with hematological disorders and BSIs. It served as a significant early prognostic indicator for hematological patients who develop BSIs.