Differential Diagnosis for a 28-year-old Male with Pharyngitis for 1 Week without Relief

• Single most likely diagnosis:
  • Viral pharyngitis: This is the most common cause of pharyngitis in adults, often resulting from infections such as the common cold or mononucleosis. The lack of relief after one week could indicate a persistent viral infection or a secondary bacterial infection.
• Other Likely diagnoses:
  • Streptococcal pharyngitis (Strep throat): A bacterial infection caused by Group A beta-hemolytic streptococci, which can present with severe sore throat, fever, and swollen lymph nodes. It's a common cause of pharyngitis that requires antibiotic treatment.
  • Infectious mononucleosis: Caused by the Epstein-Barr virus, this condition can lead to prolonged pharyngitis, fever, and fatigue, often accompanied by lymphadenopathy and splenomegaly.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed):
  • Lemierre's syndrome: A rare but potentially life-threatening condition that starts with pharyngitis, followed by a bacterial infection of the jugular vein, leading to sepsis and embolic events. It's crucial to consider this diagnosis in patients with persistent or severe pharyngitis.
  • Peritonsillar abscess: A complication of tonsillitis where an abscess forms beside the tonsils, causing severe throat pain, difficulty swallowing, and fever. It requires prompt medical attention and possibly surgical drainage.
  • Epiglottitis: An inflammation of the epiglottis that can lead to airway obstruction, which is a medical emergency. Although more common in children, it can occur in adults, especially those with compromised immune systems.
• Rare diagnoses:
  • Diphtheria: A bacterial infection caused by Corynebacterium diphtheriae, characterized by a membrane covering the tonsils and throat, which can lead to respiratory and cardiac complications. It's rare in developed countries due to vaccination but should be considered in unvaccinated individuals or those traveling from endemic areas.
  • Gonococcal pharyngitis: A sexually transmitted infection caused by Neisseria gonorrhoeae, which can present with pharyngitis, often without other symptoms. It's essential to consider this diagnosis in sexually active individuals, especially those with a history of sexually transmitted infections.