Differential Diagnosis

The patient's symptoms of a sore throat, itchy ears, feverish feeling, productive cough, and shortness of breath suggest a respiratory infection. The presence of a reddish tinge to the phlegm, which the patient believes was blood, and the trigger of colder air exacerbating the cough, along with a history of smoking, point towards several potential diagnoses. Here is a categorized differential diagnosis:

• Single Most Likely Diagnosis

  • Acute Bronchitis: This is the most likely diagnosis given the patient's symptoms of productive cough, shortness of breath, and the fact that colder air triggers coughing. The history of smoking also increases the risk for bronchitis.

• Other Likely Diagnoses

  • Pneumonia: The presence of a fever, productive cough, and shortness of breath could indicate pneumonia, especially if the coughed-up phlegm was indeed bloody, which could suggest a bacterial infection.
  • Influenza: Given the acute onset of symptoms like feeling feverish, sore throat, and cough, influenza is a plausible diagnosis, especially during flu season.
  • Acute Sinusitis: The itchy ears and sore throat could be related to sinusitis, especially if there's an accompanying postnasal drip that's irritating the throat and ears.

• Do Not Miss Diagnoses

  • Pulmonary Embolism: Although less likely, the shortness of breath and history of smoking (which increases the risk of cardiovascular diseases) make it crucial not to miss a potential pulmonary embolism, which can be life-threatening.
  • Lung Cancer: Given the patient's history of smoking, even though it was 30 years ago, lung cancer should be considered, especially if the hemoptysis (coughing up blood) is confirmed.
  • Tuberculosis (TB): The productive cough and shortness of breath, along with the potential for hemoptysis, necessitate considering TB, especially if the patient has been exposed or has risk factors.

• Rare Diagnoses

  • Bronchiectasis: This condition, characterized by damaged airways, could explain the chronic productive cough and shortness of breath but is less likely without additional symptoms like chronic sputum production.
  • Sarcoidosis: This autoimmune disease can affect the lungs and cause symptoms like cough and shortness of breath but is less common and would typically present with other systemic symptoms.
  • Histoplasmosis: A fungal infection that can cause respiratory symptoms similar to pneumonia or bronchitis, especially in individuals who have been exposed to bird or bat droppings. It's less likely without specific exposure history but should be considered in endemic areas.