c-D-index is a risk factor for prolonged febrile neutropenia during chemotherapy in patients with acute myeloid leukemia

Background D-index is a recently established clinical tool for assessing neutropenia severity. This study examined whether the D-index can predict the onset of various infections in patients with febrile neutropenia (FN). Methods We retrospectively investigated FN events in consecutive patients aged < 65 years who were treated for newly diagnosed acute myeloid leukemia at our institution. We collected data on all FN events during chemotherapy and evaluated the association of FN severity with infectious events. Results: This study included 35 patients (18 women and 17 men; median age, 51 years [range 18–65 years]) with 122 FN events. The response rate to induction chemotherapy was 60% (21/35), and all but one patient survived the treatment. The D-index did not predict FN onset. However, in multivariate analysis, high-dose cytarabine and total D-index were statistically significant explanatory factors for microbiological-proven infections. In addition, multivariate analysis showed that diabetes mellitus is the only risk factor for FN onset. Furthermore, older age, consolidation therapy, and cumulative D-index (c-D-index) were risk factors for prolonged FN. The FN period was the longest in patients with respiratory infections. Conclusion The D-index did not predict the onset of infection. However, FN duration might be prolonged during consolidation therapy in elderly patients with diabetes mellitus, and it is important to manage respiratory infections. These findings indicate the c-D-index is a useful tool to predict prolonged FN.