A 19-year-old college student presents with two weeks of fever, exudative tonsillitis, and posterior cervical lymphadenopathy. Examination reveals splenomegaly. Peripheral smear shows large atypical lymphocytes, and the serum heterophile antibody (Paul-Bunnell) test is positive. Which virus is responsible?
- A Cytomegalovirus
- B Human herpesvirus 6
- C Epstein-Barr virus ✓
- D Adenovirus
Correct answer: C. Epstein-Barr virus
Explanation
The triad of fever, pharyngitis and lymphadenopathy with splenomegaly, atypical lymphocytes (activated CD8+ T cells) and a positive heterophile antibody test defines classic infectious mononucleosis caused by primary Epstein-Barr virus infection. CMV mononucleosis is heterophile negative and typically lacks prominent pharyngitis. HHV-6 causes roseola in infants, and adenovirus produces pharyngitis without the characteristic hematologic picture.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.