Expected CBC Changes When Increasing Prednisone from 10mg to 20mg
When increasing a patient's prednisone dose from 10mg to 20mg daily, you can expect to see an increase in white blood cell count (leukocytosis) with neutrophilia, along with decreases in lymphocytes and eosinophils.
Primary Changes on CBC with Differential
White Blood Cell Count (WBC)
- Increased total WBC count (leukocytosis)
- May reach levels above 20,000/mm³ within days of dose increase 1
- Effect is dose-dependent and occurs more rapidly with higher doses
Differential Changes
- Neutrophils: Increased (neutrophilia)
- Lymphocytes: Decreased (lymphopenia)
- Eosinophils: Decreased (eosinopenia)
- Monocytes: Variable response - may show increase (monocytosis) 1
Red Blood Cell Parameters
- Generally minimal immediate changes
- Potential slight increase in hemoglobin and hematocrit over time
Platelets
- Usually minimal changes in count
- Potential decrease in mean platelet volume 2
Timing and Duration of Changes
The hematologic effects of increasing prednisone dosage follow a predictable pattern:
Immediate effects (within 24-48 hours):
- Initial leukocytosis with neutrophilia
- Early lymphopenia and eosinopenia
Peak effects (1-2 weeks):
- Maximal leukocytosis typically occurs within two weeks 1
- Most pronounced changes in differential counts
Adaptation (beyond 2 weeks):
- WBC count may decrease somewhat but typically remains elevated above baseline
- Differential changes persist throughout treatment duration
Clinical Significance and Interpretation
- The leukocytosis is primarily due to demargination of neutrophils and delayed apoptosis rather than increased production
- These changes represent a redistribution effect rather than true bone marrow stimulation
- Important distinction: Prednisone-induced leukocytosis typically lacks a "left shift" (increased band forms) and toxic granulation that would suggest infection 1
Monitoring Recommendations
- Baseline CBC with differential before dose increase
- Follow-up CBC 1-2 weeks after dose increase to assess peak effect
- Periodic monitoring during continued treatment
- Consider more frequent monitoring if patient has pre-existing hematologic conditions
Potential Confounding Factors
- Underlying disease process may influence hematologic parameters
- Concurrent medications may modify expected changes
- Individual patient variability in response to corticosteroids
Remember that these changes are expected physiologic responses to increased corticosteroid dosage and do not necessarily indicate pathology. The most sensitive indicators of long-term glucocorticoid effect are the eosinophil and lymphocyte counts 2.