Which finding would support a diagnosis of infectious mononucleosis in a preschooler?

Which finding would support a diagnosis of infectious mononucleosis in a preschooler?

• A. Splenomegaly
• B. Non-tender abdominal mass
• C. Cyanosis
• D. Brisk capillary refill

Answer: (A)

An enlarged spleen is a classic finding in infectious mononucleosis. In EBV infection, there is proliferation of lymphoid tissue that often enlarges the spleen, so a palpable increase in spleen size in a preschooler with compatible symptoms strongly supports the diagnosis. Clinically, you may detect splenomegaly as fullness in the left upper quadrant, and it carries the important precaution of avoiding contact sports or trauma to prevent splenic rupture while it remains enlarged. Remember that mono is usually confirmed with a Monospot (heterophile) test or EBV-specific serology, and a CBC often shows lymphocytosis with atypical lymphocytes. The other options—signs like cyanosis or poor perfusion—do not fit infectious mononucleosis, and a non-tender abdominal mass could reflect splenomegaly but does not point to mono as directly as the presence of an enlarged spleen does.

An enlarged spleen is a classic finding in infectious mononucleosis. In EBV infection, there is proliferation of lymphoid tissue that often enlarges the spleen, so a palpable increase in spleen size in a preschooler with compatible symptoms strongly supports the diagnosis. Clinically, you may detect splenomegaly as fullness in the left upper quadrant, and it carries the important precaution of avoiding contact sports or trauma to prevent splenic rupture while it remains enlarged. Remember that mono is usually confirmed with a Monospot (heterophile) test or EBV-specific serology, and a CBC often shows lymphocytosis with atypical lymphocytes. The other options—signs like cyanosis or poor perfusion—do not fit infectious mononucleosis, and a non-tender abdominal mass could reflect splenomegaly but does not point to mono as directly as the presence of an enlarged spleen does.