In a 14-year-old boy with a sore throat and dullness in the last intercostal space, what might this signify?

The indication of dullness in the last intercostal space in a 14-year-old boy with a sore throat could signify an enlarged spleen, often referred to as splenomegaly. In a clinical context, splenomegaly can present with dullness upon percussion in the left lower thoracic area, where the spleen is anatomically located. This is particularly relevant in cases where an infection or systemic illness is present, such as mononucleosis or other viral infections that can cause lymphoid tissue, including the spleen, to enlarge.

While liver enlargement might also cause a dullness in this region, it is typically associated with different percussion notes in the right upper quadrant rather than the left intercostal space. Pneumonia can present with dullness, but it is usually accompanied by signs of respiratory distress, abnormal lung sounds, and findings that change from the normal expected percussion note. Pleural effusion, while capable of causing dullness as well, is more commonly associated with higher intercostal spaces and would likely present with additional respiratory symptoms and findings such as increased respiratory rate or decreased breath sounds over the affected area.

Thus, given the symptomatology and the anatomical considerations, an enlarged spleen is the