Differential Diagnosis for a 78-year-old Woman with Repeated Coughing and Throat Clearing

Single Most Likely Diagnosis

• Gastroesophageal Reflux Disease (GERD): This condition is common in the elderly and can cause symptoms of coughing and throat clearing due to the reflux of stomach acid into the esophagus, irritating the throat and triggering a cough reflex. The sensation of a mucus plug could be due to the chronic irritation and inflammation.

Other Likely Diagnoses

• Chronic Bronchitis: Part of chronic obstructive pulmonary disease (COPD), chronic bronchitis involves inflammation of the bronchial tubes, leading to a persistent cough and mucus production, which could be perceived as a mucus plug.
• Postnasal Drip (Upper Airway Secretion Syndrome): This condition, often due to allergies or a cold, can cause a sensation of mucus running down the back of the throat, leading to frequent throat clearing and coughing.
• Asthma: Although more commonly diagnosed in younger individuals, asthma can occur at any age. Coughing, especially at night, and the sensation of mucus or a plug in the throat could be symptoms of asthma.

Do Not Miss Diagnoses

• Lung Cancer: Although less likely, lung cancer must be considered, especially in older adults, as it can present with a persistent cough and sensation of something being stuck in the throat due to a tumor obstructing an airway.
• Pulmonary Embolism: While typically presenting with sudden onset of dyspnea and chest pain, in some cases, a pulmonary embolism could cause coughing. It's a critical diagnosis not to miss due to its high mortality rate if untreated.
• Foreign Body Aspiration: Accidental inhalation of food or other objects can cause sudden onset of coughing and a sensation of obstruction, which is an emergency requiring immediate attention.

Rare Diagnoses

• Vocal Cord Dysfunction: This condition involves abnormal movement of the vocal cords, which can cause symptoms similar to asthma, including coughing and a feeling of throat obstruction.
• Relapsing Polychondritis: A rare autoimmune disorder that can cause inflammation of the cartilaginous structures in the body, including the trachea, leading to coughing and respiratory symptoms.
• Sarcoidosis: An autoimmune disease that can affect multiple parts of the body, including the lungs, causing coughing, among other symptoms, due to granulomatous inflammation.