AANP Family Nurse Practitioner (FNP) Certification ExamDiagnosisMedium
A 22-year-old female presents with a 3-week history of profound fatigue, generalized weakness, sore throat, and low-grade fever. She reports recently attending several social gatherings. Physical examination reveals bilateral posterior cervical lymphadenopathy, tonsillar exudates, and mild hepatosplenomegaly. Rapid strep test is negative. What is the most likely diagnosis?
- ACytomegalovirus (CMV) infection
- BStreptococcal pharyngitis
- CAcute HIV infection
- DInfectious Mononucleosis
Show answer & explanationAnswer & explanation
Correct answer: D. Infectious Mononucleosis
The patient's age, prolonged fatigue, sore throat, fever, posterior cervical lymphadenopathy, tonsillar exudates, and hepatosplenomegaly, especially with a negative rapid strep test, are classic findings for infectious mononucleosis, typically caused by Epstein-Barr Virus (EBV).
Why the other options are wrong
- A. CMV can cause a mononucleosis-like syndrome, but it's less common in this age group, and posterior cervical lymphadenopathy and tonsillar exudates are less prominent than in EBV mononucleosis.
- B. Streptococcal pharyngitis would typically present with a more acute onset, prominent anterior cervical lymphadenopathy, and a positive rapid strep test. Prolonged fatigue and hepatosplenomegaly are not typical.
- C. Acute HIV infection can cause a mononucleosis-like syndrome with fever, rash, and lymphadenopathy, but typically does not involve prominent tonsillar exudates or hepatosplenomegaly as primary features, and the fatigue is usually less profound in the initial acute phase compared to mono.
Infectious Mononucleosis
An infectious disease, typically caused by the Epstein-Barr Virus (EBV), characterized by fever, sore throat, fatigue, and lymphadenopathy, often with hepatosplenomegaly.
- Commonly affects adolescents and young adults.
- Classic triad: fever, pharyngitis, lymphadenopathy (often posterior cervical).
- Diagnosis confirmed by heterophile antibody test (Monospot) or EBV serology.
Memory trick: MONO: Mononucleosis Often Nags with Ongoing fatigue.