Differential Diagnosis for the Patient's Cough

The patient presents with a worsening nonproductive cough, orthopnea, increased fatigue, shortness of breath, and swelling of the ankles, along with a history of hypertension. These symptoms suggest a cardiovascular origin, but other causes must be considered.

• Single Most Likely Diagnosis

  • Heart Failure: The patient's symptoms of orthopnea (cough worsening when lying flat), increased fatigue, shortness of breath while walking, swelling of the ankles, basilar rhonchi, S3 heart sound, and lower extremity edema are classic for heart failure. The past medical history of hypertension, a major risk factor for heart failure, further supports this diagnosis.

• Other Likely Diagnoses

  • Gastroesophageal Reflux (GERD): Although the patient's symptoms are more suggestive of heart failure, GERD can cause a chronic cough, especially if the patient experiences reflux at night, which could worsen when lying flat. However, the absence of typical GERD symptoms like heartburn makes this less likely.
  • Bronchitis: While bronchitis can cause a cough, the patient's cough is nonproductive, and there's no mention of fever or chills, which are common in bronchitis. The patient's symptoms are more systemic and suggestive of a cardiopulmonary issue rather than a pure respiratory infection.
  • Postnasal Drip: This could cause a chronic cough, but the patient's other symptoms (orthopnea, edema, S3 heart sound) are not explained by postnasal drip alone.

• Do Not Miss Diagnoses

  • Pulmonary Embolism: Although less likely given the patient's presentation, pulmonary embolism is a critical diagnosis that must be considered, especially with symptoms like shortness of breath. However, the lack of sudden onset, chest pain, or significant desaturation on room air makes this less probable. Still, it's a diagnosis that could be deadly if missed, and further evaluation might be warranted based on clinical judgment and additional testing.

• Rare Diagnoses

  • Other rare causes of cough, such as pulmonary lymphangitic carcinomatosis, sarcoidosis, or other infiltrative lung diseases, could be considered but are less likely given the patient's presentation and the absence of other suggestive symptoms or findings. These would typically require more specific diagnostic testing to confirm.