Differential Diagnosis for Cough with Yellow Sputum
Single Most Likely Diagnosis
- Acute Bronchitis: This is often the most common cause of cough with yellow sputum, typically resulting from a viral or bacterial infection. The yellow color of the sputum is due to the presence of pus, which is a mixture of dead white blood cells, bacteria, and cellular debris.
Other Likely Diagnoses
- Chronic Obstructive Pulmonary Disease (COPD) Exacerbation: Patients with COPD can experience worsening of symptoms, including cough with colored sputum, due to an exacerbation, often triggered by a respiratory infection or air pollution.
- Pneumonia: Both community-acquired and hospital-acquired pneumonia can present with cough and yellow or green sputum, depending on the causative organism.
- Asthma: Although asthma is characterized by wheezing, cough can be a predominant symptom, especially in cough-variant asthma, and may be accompanied by yellow sputum if there is a secondary infection.
Do Not Miss Diagnoses
- Lung Abscess: A serious condition that requires prompt diagnosis and treatment, characterized by a localized collection of pus within the lung tissue, which can present with cough, fever, and foul-smelling sputum.
- Tuberculosis (TB): Although less common in some regions, TB is a critical diagnosis not to miss, as it can present with chronic cough, sometimes with yellow or blood-tinged sputum, and requires specific treatment to prevent complications and transmission.
- Pulmonary Embolism: While typically presenting with sudden onset of dyspnea and chest pain, in some cases, pulmonary embolism can cause cough, and if associated with infarction, may produce yellow or bloody sputum.
Rare Diagnoses
- Cystic Fibrosis: A genetic disorder leading to persistent lung infections and progressive lung damage, which can cause chronic cough with thick, yellow or green sputum.
- Bronchiectasis: A condition characterized by damaged, dilated airways, leading to chronic cough, large volumes of sputum production, and recurrent infections.
- Aspiration Pneumonia: Can occur when food, liquids, vomit, or saliva is inhaled into the lungs, potentially causing cough with discolored sputum, especially if there is a secondary infection.