Purpose

Neutropenia, defined as a number of neutrophils in patients’ blood specimen lower than 1500 cells/μm³, is a common adverse event during myelosuppressive oncological chemotherapy, predisposing to febrile neutropenia (FN). Patients with coexisting moderate-to-severe chronic kidney disease (CKD) have an increased risk of FN, included in the guidelines for the primary prophylaxis of FN. However, this does not include mild kidney function impairment with estimated glomerular filtration rate (eGFR) 60–89 ml/min/1.73 m². This prospective study analyzed the risk of neutropenia in patients on chemotherapy without indication for the primary prophylaxis of FN.

Methods

The study enrolled 38 patients starting chemotherapy, including 26 (68.4%) patients aged 65 years or more. The median duration of follow-up was 76 days. The methodology of creatinine assessment enabled the use of the recommended CKD-EPI formula for identifying patients with a mild reduction of glomerular filtration.

Results

Sixteen (42.1%) patients developed at least G2 neutropenia without episodes of FN. Only five (13.1%) patients had eGFR < 60 ml/min/1.73 m², while 15 (62.5%) eGFR < 90 ml/min/1.73 m². The relative risk of neutropenia in patients with impaired eGFR was over six times higher than in patients with eGFR > 90 ml/min/1.73 m² (RR = 6.08; 95%CI:1.45–27.29; p < 0.01).

Conclusions

Our observation indicates that even a mild reduction in eGFR is a risk factor for the development of neutropenia and a potential risk factor for FN. Authors are advised to check the author instructions for the journal they are submitting to for word limits and if structural elements like subheadings, citations, or equations are permitted.