ANC Calculation
The Absolute Neutrophil Count (ANC) is 30 cells/mm³, calculated as: (Total WBC × % neutrophils) = (500 × 0.06) = 30 cells/mm³.
Critical Clinical Context
This patient has profound neutropenia (ANC <100 cells/mm³), placing them at very high risk for life-threatening infections. 1, 2
Important Caveat About This Differential
- This differential count is unreliable because it was performed on only 10 cells. 3
- Standard differential counts require evaluation of at least 100 cells to provide statistically valid percentages. 3
- A 10-cell differential has an unacceptably high margin of error and should not be used for clinical decision-making. 3
- This result must be repeated with an adequate cell count before making treatment decisions. 3
Neutropenia Classification
Based on the calculated ANC of 30 cells/mm³:
- This represents Grade 4 (profound) neutropenia, defined as ANC <100 cells/mm³. 2, 4
- The Infectious Diseases Society of America defines severe neutropenia as ANC <500 cells/mm³, with profound neutropenia at <100 cells/mm³ carrying the highest infection risk. 1, 2
Immediate Clinical Actions Required
If This Count Is Accurate:
- Implement broad-spectrum prophylactic antimicrobial therapy immediately (fluoroquinolone prophylaxis with levofloxacin or ciprofloxacin). 1, 2
- Consider G-CSF therapy for anticipated prolonged neutropenia (>7 days). 2
- Perform daily clinical assessment and CBC monitoring until ANC ≥500 cells/mm³. 2
- If fever develops (>38.5°C for >1 hour), this constitutes febrile neutropenia—a medical emergency requiring immediate empiric broad-spectrum antibiotics. 1, 2
Priority Action:
Repeat the complete blood count with a proper 100-cell manual differential immediately to confirm this critically low ANC before initiating aggressive interventions. 3