What does it mean when a baby's blood test shows elevated levels?

A high blood count in infants usually refers to a white blood cell (WBC) count exceeding the normal range in a complete blood count (CBC) test, indicating elevated WBC levels. This may be caused by various factors, including physiological and pathological reasons. Physiological causes include situations such as intense crying, vigorous physical activity, or frequent vomiting during the blood test, which may temporarily elevate the white blood cell count beyond the normal range. Pathological causes are more complex and may include bacterial infections, viral infections, and other disease-related factors. For example, bacterial infections such as pyogenic infections (e.g., tonsillitis, pneumonia) can trigger localized or systemic inflammatory responses, leading to increased white blood cell counts. Viral infections, such as Epstein-Barr virus (EBV), can also cause a significant rise in blood counts. If a high blood count is detected, it is recommended to seek medical attention promptly to determine the underlying cause and receive appropriate treatment.