Differential Diagnosis

The patient presents with symptoms of a chest infection, including chest burning, cough with green phlegm, fever, and shortness of breath. The following differential diagnoses are considered:

• Single Most Likely Diagnosis
  • Acute bronchitis: The patient's symptoms of cough with green phlegm, fever, and chest burning are consistent with acute bronchitis, a common condition in adults, especially in those with a history of smoking.
• Other Likely Diagnoses
  • Community-acquired pneumonia (CAP): Although the patient's oxygen saturation is normal and there are no crackles on lung exam, CAP is still a possibility, especially given the fever, cough, and green phlegm.
  • Acute exacerbation of asthma: The patient has a history of asthma, and although it is reported as inactive, the symptoms of cough, shortness of breath, and chest burning could be indicative of an exacerbation.
  • Influenza: The patient's symptoms of fever, cough, and sore throat, although mild, could be consistent with influenza, especially during the flu season.
• Do Not Miss Diagnoses
  • Pulmonary embolism (PE): Although the patient's symptoms do not strongly suggest PE, it is a potentially life-threatening condition that must be considered, especially in patients with risk factors such as recent surgery or immobility.
  • Myocardial infarction (MI): The patient's chest pain described as a burning sensation could be atypical for MI, and although the patient's cardiovascular exam is normal, MI must be considered in any patient with chest pain.
  • Pneumonia due to a more unusual organism (e.g., Legionella, Mycoplasma): These organisms can cause atypical presentations of pneumonia, and a high index of suspicion is necessary to diagnose them.
• Rare Diagnoses
  • Tuberculosis (TB): Although the patient's symptoms are not strongly suggestive of TB, it is a possibility, especially in patients with a history of smoking or other risk factors.
  • Lung cancer: The patient's history of smoking and recent onset of symptoms could raise the possibility of lung cancer, although it is less likely given the acute presentation.
  • Sarcoidosis: This condition can cause a variety of respiratory symptoms, including cough and shortness of breath, although it is less likely given the patient's acute presentation.