Differential Diagnosis for 20 yo College Male with Fever, Runny Nose, Conjunctivitis, and Maculopapular Rash

• Single Most Likely Diagnosis
  • Infectious Mononucleosis (Mono): Caused by Epstein-Barr virus (EBV), it often presents with fever, sore throat, and fatigue, but can also include symptoms like conjunctivitis and a maculopapular rash, especially after the administration of ampicillin, which this patient might have been given for a presumed bacterial infection.
• Other Likely Diagnoses
  • Adenovirus Infection: Adenoviruses can cause a range of symptoms including fever, runny nose, conjunctivitis, and rash, making it a plausible diagnosis given the patient's symptoms.
  • Enterovirus Infection: Enteroviruses are known to cause a variety of clinical manifestations, including fever, rash, and conjunctivitis, particularly in young adults.
• Do Not Miss Diagnoses
  • Meningococcal Disease: Although less common, meningococcal disease can present with fever, rash, and conjunctivitis, and is a medical emergency due to its high mortality rate if not promptly treated.
  • Kawasaki Disease: An acute febrile illness that predominantly affects children but can occur in young adults, characterized by fever, conjunctivitis, rash, and other symptoms. It's crucial to diagnose and treat promptly to prevent cardiac complications.
• Rare Diagnoses
  • Rickettsial Infections (e.g., Rocky Mountain Spotted Fever): These infections can cause fever, rash, and conjunctivitis, but are less common and typically associated with specific geographic or exposure histories.
  • Secondary Syphilis: Can present with a maculopapular rash, fever, and other systemic symptoms, including conjunctivitis, though it's less likely without other specific risk factors or symptoms.