Absolute Neutrophil Count (ANC) Calculation
The ANC from this CBC is 1.6 × 10⁹/L (1,600/µL), calculated by adding segmented neutrophils absolute (1.5) + bands absolute (0.1), which represents mild neutropenia. 1
Calculation Method
The ANC is determined by summing all mature and near-mature neutrophil forms in their absolute counts 1:
- Segmented neutrophils (absolute): 1.5 × 10⁹/L
- Bands (absolute): 0.1 × 10⁹/L
- Total ANC = 1.5 + 0.1 = 1.6 × 10⁹/L
Note that while metamyelocytes (0.1) and myelocytes (0.0) are present, these immature forms are not included in the standard ANC calculation for clinical decision-making, though their presence indicates a left shift. 2
Neutropenia Classification
This patient has mild neutropenia based on the National Comprehensive Cancer Network classification 1:
- Mild neutropenia: ANC 1.0-1.5 × 10⁹/L (this patient is at 1.6, just above this threshold)
- Moderate neutropenia: ANC 0.5-1.0 × 10⁹/L 1
- Severe neutropenia: ANC <0.5 × 10⁹/L 1
Clinical Significance and Management
For this ANC of 1.6 × 10⁹/L, regular CBC monitoring is recommended but prophylactic antimicrobial therapy is not indicated 1:
- No antimicrobial prophylaxis needed at this level 1
- Monitor CBC regularly, especially if the patient is receiving myelosuppressive therapy 1
- Prophylactic antimicrobials are only indicated when ANC drops below 0.5 × 10⁹/L 1, 3
Important Caveats
Febrile neutropenia is a medical emergency defined as fever >38.5°C for >1 hour with ANC <0.5 × 10⁹/L 1:
- Even with mild neutropenia (ANC 1.0-1.5 × 10⁹/L), patients who develop fever should be evaluated further 1
- The risk of serious infection increases significantly when ANC falls below 0.5 × 10⁹/L 1
Additional concerning features in this CBC that warrant attention beyond the ANC calculation:
- Severe anemia (Hemoglobin 8.4 g/dL, Hematocrit 24.6%) 4
- Leukopenia (WBC 2.9 × 10⁹/L) 4
- Presence of immature myeloid cells (metamyelocytes, myelocytes) 4
- Toxic granulation, Döhle bodies, and vacuolated polymorphonuclear cells suggest active infection or severe stress 2
- Nucleated RBCs present (1.4%) 4
If this patient is receiving chemotherapy, even this level of mild neutropenia warrants closer monitoring, and G-CSF therapy should be considered if ANC continues to decline toward 0.5 × 10⁹/L 3.