Normal White Blood Cell Count Range for 8-Year-Old Children
The normal white blood cell (WBC) count range for an 8-year-old child is approximately 4,500-13,500 cells/mm³.
Age-Specific WBC Reference Ranges
According to the National Health and Nutrition Examination Survey (NHANES) data, the normal WBC count range for children aged 6-8 years is:
- Mean WBC count: approximately 8,000 cells/mm³
- Normal range: 4,500-13,500 cells/mm³ 1
This range reflects the typical variation seen in healthy children of this age group. The table from the NHANES data indicates that for children aged 6-8 years, the 5th percentile is around 5,000 cells/mm³ and the 95th percentile is approximately 13,500 cells/mm³.
Differential White Blood Cell Count
For a complete assessment, the differential count is also important:
- Neutrophils: 40-60% of total WBC
- Lymphocytes: 30-50% of total WBC
- Monocytes: 4-10% of total WBC
- Eosinophils: 1-4% of total WBC
- Basophils: 0-1% of total WBC
Clinical Significance of Abnormal WBC Counts
Elevated WBC Count (Leukocytosis)
- Mild elevation (13,500-15,000 cells/mm³): Often seen with viral infections or mild bacterial infections
- Moderate elevation (15,000-20,000 cells/mm³): May indicate bacterial infection, inflammation, or stress response
- Significant elevation (>20,000 cells/mm³): Higher likelihood of bacterial infection
- Extreme leukocytosis (>35,000 cells/mm³): Associated with serious disease in 26% of pediatric cases and bacteremia in 10% 2
Low WBC Count (Leukopenia)
- Mild leukopenia (3,000-4,500 cells/mm³): May be seen with certain viral infections
- Moderate to severe leukopenia (<3,000 cells/mm³): Could indicate bone marrow suppression, severe infection, or medication effect
Diagnostic Value in Common Conditions
Bacterial vs. Viral Infections
- WBC counts >15,000 cells/mm³ have a specificity of 86% for bacterial infections in children
- WBC counts >20,000 cells/mm³ have a specificity of 95% for bacterial infections 3
- However, normal WBC counts do not rule out bacterial infections, as sensitivity is relatively low
Appendicitis
In children aged 4-11.9 years with suspected appendicitis:
- Elevated WBC count has a sensitivity of 71% and specificity of 72%
- Left shift (increased immature neutrophils) has a sensitivity of 59% and specificity of 90%
- Combined elevated WBC and left shift has a sensitivity of 80% and specificity of 79% 4
Important Considerations
Recent research indicates that WBC count alone has limited value in identifying serious bacterial infections compared to other markers like C-reactive protein (CRP) 5
WBC count should be interpreted in the context of:
- Clinical presentation
- Duration of symptoms
- Presence of other laboratory abnormalities
- Age-specific reference ranges
Serial measurements may be more valuable than a single reading, especially when monitoring response to treatment
Extreme values (very high or very low) generally have more clinical significance than borderline abnormal values
Remember that while these ranges represent population norms, individual variation exists, and clinical context is essential for proper interpretation of laboratory values.