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Differential Diagnosis for Infectious Mononucleosis (IM)

Single Most Likely Diagnosis

  • Infectious Mononucleosis (IM): Caused by Epstein-Barr virus (EBV), presenting with fever, sore throat, lymphadenopathy, and fatigue. This is the most likely diagnosis given the classic symptoms associated with IM.

Other Likely Diagnoses

  • Streptococcal Pharyngitis: Presents with sore throat, fever, and lymphadenopathy, similar to IM, but is caused by Group A beta-hemolytic streptococcus.
  • Cytomegalovirus (CMV) Infection: Can mimic IM, especially in immunocompromised patients, with symptoms like fever, fatigue, and lymphadenopathy.
  • Toxoplasmosis: Although less common, can present with similar symptoms to IM, particularly in immunocompromised individuals.

Do Not Miss Diagnoses

  • Hodgkin Lymphoma: Although rare, it can present with lymphadenopathy and systemic symptoms similar to IM. Missing this diagnosis could have severe consequences.
  • Acute Lymphoblastic Leukemia (ALL): Presents with symptoms that can overlap with IM, such as fatigue, lymphadenopathy, and hepatosplenomegaly. Early diagnosis is crucial for treatment.
  • AIDS (Acquired Immunodeficiency Syndrome): Can present with persistent fever, lymphadenopathy, and fatigue, similar to IM. Diagnosis of AIDS is critical for appropriate management and treatment.

Rare Diagnoses

  • Human Immunodeficiency Virus (HIV) Acute Retroviral Syndrome: Presents with symptoms similar to IM, including fever, rash, and lymphadenopathy, occurring shortly after HIV infection.
  • Infectious Diseases like Tuberculosis or Brucellosis: Although less common, these infections can present with systemic symptoms and lymphadenopathy, mimicking IM in some cases.
  • Autoimmune Lymphoproliferative Syndrome (ALPS): A rare condition that can present with lymphadenopathy, splenomegaly, and cytopenias, potentially mimicking IM.

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This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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