Implementation of a Duffy antigen screening test order with interpretation guide to help optimize resource allocation at an urban safety‐net hospital

Neutropenia workups comprise 6%–27% of hematology referrals.1-3 A subset of patients with Duffy-null phenotype can be erroneously identified as having neutropenia due to an absolute neutrophil count (ANC) <1500 × 103/μL, a condition referred to as Duffy-null associated neutrophil count (DANC). These individuals are not at increased risk of infections.4 The Duffy-null phenotype is reported in 66.7% of black and African American individuals in the United States.5 Boston Medical Center (BMC) is a safety-net hospital primarily serving low- and middle-income African American, Hispanic, and immigrant communities. Historically, to assess Duffy status, clinicians order a “RBC phenotype” then specify “Duffy antigens only” within the comments. For streamlining, we created a distinct “Duffy Antigen Screening” test order within our electronic health record (EPIC). Results include an interpretation guide (Figure 1). Information technology ensured seamless integration between the laboratory information system (Sunquest) and patient charts. Hematologists promote order usage amongst clinicians using online and in-person presentations generating a 66.1% increase in testing in 2024 (n = 274) after implementation, compared to the same period in 2023 (n = 165) (Figure 2). Orders were placed for patients who either were receiving anti-CD38 antibodies or were suspected of having DANC. In 2023, 73.9% (122/165) of tested patients had the Duffy-null phenotype compared to 77.6% (229/274) of patients in 2024. BMC has validated the published Duffy null-specific ANC reference range as part of the American Society of Hematology ANC by Duffy status project (www.hematology.org/diversity-equity-and-inclusion/danc). Centers may use similar strategies to increase DANC awareness and optimize healthcare utilization by minimizing unnecessary hematology referrals. The authors declare no conflicts of interest.