Differential Diagnosis

The patient presents with fever, dry cough, sore throat, and poor appetite. Based on the provided information, the following differential diagnoses are considered:

• Single most likely diagnosis
  • Viral pharyngitis: The patient's symptoms of fever, sore throat, and cough, along with the absence of chest pain, rash, nausea, or vomiting, and a normal throat swab culture, suggest a viral etiology. The presence of a red and slightly swollen throat with visible tonsils further supports this diagnosis.
• Other Likely diagnoses
  • Bacterial pharyngitis: Although the throat swab culture is pending, the patient's symptoms could also be consistent with a bacterial infection, such as streptococcal pharyngitis. The presence of a sore throat and fever supports this possibility.
  • Influenza: The patient's symptoms of fever, cough, and sore throat, along with the time of year and lack of sick contacts, could suggest influenza. However, the absence of body aches and fatigue makes this diagnosis less likely.
  • Acute bronchitis: The patient's cough and fever could be consistent with acute bronchitis, although the absence of wheezing or crackles on lung exam makes this diagnosis less likely.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Epiglottitis: Although the patient does not have stridor or significant respiratory distress, epiglottitis is a life-threatening condition that requires prompt recognition and treatment. The presence of a sore throat and fever, along with the patient's age, makes this diagnosis a "do not miss" consideration.
  • Pneumonia: The patient's cough and fever could be consistent with pneumonia, although the absence of chest pain, wheezing, or crackles on lung exam makes this diagnosis less likely. However, pneumonia can be a serious and life-threatening condition, especially in pediatric patients.
  • Peritonsillar abscess: The patient's sore throat and fever, along with the presence of a blue discoloration on the tonsil (likely from a lollipop), could suggest a peritonsillar abscess. Although this diagnosis is less likely, it is a serious condition that requires prompt recognition and treatment.
• Rare diagnoses
  • Lemierre's syndrome: This rare condition is characterized by a bacterial infection of the tonsils, followed by sepsis and thrombophlebitis of the internal jugular vein. Although the patient's symptoms do not strongly suggest this diagnosis, it is a rare but serious condition that should be considered in the differential diagnosis.
  • Infectious mononucleosis: The patient's sore throat, fever, and fatigue could be consistent with infectious mononucleosis, although the absence of lymphadenopathy and splenomegaly makes this diagnosis less likely.