What viral infection is indicated by an increase in white blood cells and can cause spleen enlargement?

The viral infection indicated by an increase in white blood cells and the potential for spleen enlargement is mononucleosis. Mononucleosis, often caused by the Epstein-Barr virus, is characterized by a significant increase in atypical lymphocytes, which are a type of white blood cell. This condition leads to systemic symptoms such as fever, sore throat, fatigue, and notably, splenomegaly, or enlargement of the spleen.

The relationship between mononucleosis and elevated white blood cell counts stems from the body’s immune response to the viral infection. The immune system mobilizes lymphocytes to combat the virus, leading to the characteristic laboratory findings.

On the other hand, while influenza, chickenpox, and hepatitis can also cause some immune responses, they are not characterized specifically by the same profound increase in atypical white blood cells or notable spleen enlargement that are hallmark signs of mononucleosis. Each of those infections has distinct pathophysiologies and symptom profiles that differentiate them from mononucleosis.