Re‑Thinking “Normal”: Absolute Neutrophil Count by Duffy Status

About this episode

The episode explores the implications of Absolute Neutrophil Counts by Duffy Status and the establishment of Duffy null-specific reference intervals.

Join Dr. Maureen Achebe and Dr. Lauren Merz for an in‑depth exploration of the Absolute Neutrophil Counts (ANC) by Duffy Status project, a multicenter effort to define what “normal” ANC and white blood cell counts (WBC) look like in people with the erythrocyte Duffy null variant. Using data from 23 sites across the United States, the project established Duffy null-specific ANC and WBC reference intervals for both adults and children as well as highlighted how often healthy Duffy null individuals have ANC and WBC that fall below conventional laboratory cutoffs. The episode unpacks the key findings: in healthy adults with Duffy null status, the ANC reference interval has a lower limit of normal near 1,000/µL, substantially below many institutional “normal” thresholds and far below the traditional neutropenia threshold of 1,500/uL. Similar downward shifts are seen across pediatric age groups with lower limits of normal ranging from 500/uL to 900/uL depending on age category. The faculty discuss how, under current institutional ranges, a sizeable proportion of otherwise healthy Duffy null patients are labeled as neutropenic or leukopenic which often prompts unnecessary workups…

People in this episode

Guests: Dr. Maureen Achebe, Dr. Lauren Merz

Topics covered

• Absolute Neutrophil Count
• Duffy Status
• hematology
• reference intervals
• neutropenia
• clinical trials

Keywords

• Absolute Neutrophil Count
• Duffy null variant
• white blood cell counts
• neutropenia
• laboratory cutoffs
• clinical trials
• reference intervals

Mentioned in this episode

Organizations: American Society of Hematology

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