Athletic Training Practice Exam 2026 - Free Athletic Training Practice Questions and Study Guide

The enlargement of the spleen, or splenomegaly, is most commonly associated with infectious conditions, particularly viral infections. Mononucleosis, often caused by the Epstein-Barr virus, is well-known for causing both lymphadenopathy and splenomegaly. The spleen plays a vital role in the immune response, filtering blood and removing infected or damaged cells, which explains why it becomes enlarged during infections such as mononucleosis.

In contrast to mononucleosis, Graves' disease mainly affects the thyroid and is characterized by hormonal imbalances rather than splenic enlargement. Constipation is a digestive issue that does not relate to splenic size, and appendicitis is an inflammation of the appendix, also unrelated to spleen enlargement. Therefore, mononucleosis stands out as the condition that directly impacts the spleen's size due to the body's response to the viral infection.