AANP Adult Gerontology Primary Care Nurse Practiotioner Practice

The most common lab abnormality associated with mononucleosis is lymphocytosis. Mononucleosis, often caused by the Epstein-Barr virus (EBV), typically leads to an increase in atypical lymphocytes in the bloodstream. This reflects the immune response to the viral infection, as the body increases production of lymphocytes to combat the invading pathogen.

In the context of mononucleosis, the presence of atypical lymphocytes is a hallmark finding on a complete blood count (CBC) and often correlates with clinical symptoms like fatigue, sore throat, and swollen lymph nodes. This lab finding serves as a significant indicator for diagnosing the condition alongside clinical signs.

Other abnormalities, such as neutropenia or thrombocytopenia, are less associated with mono and are more characteristic of different hematological concerns or other viral infections. Hyperkalemia, an increase in potassium levels in the blood, is not typically related to mononucleosis and would warrant evaluation for other potential causes.