Differential Diagnosis for a 5-Month-Old with a Cough that Only Happens at Night
- Single Most Likely Diagnosis
- Reactive Airway Disease (Asthma): This is a common condition in infants that can cause coughing, especially at night due to triggers like allergens, cold air, or respiratory infections. The nocturnal cough can be exacerbated by lying down.
- Other Likely Diagnoses
- Gastroesophageal Reflux Disease (GERD): GERD can cause stomach acid to flow up into the throat, leading to irritation and coughing, which may worsen when the infant is lying down at night.
- Upper Respiratory Infection: Viral infections can cause cough, which may be more noticeable at night due to the accumulation of secretions and the infant's position.
- Allergic Rhinitis: Allergies to dust mites, pet dander, or other environmental allergens can cause nasal congestion and cough, which may be worse at night.
- Do Not Miss Diagnoses
- Congenital Heart Disease: Although less common, certain congenital heart defects can lead to respiratory symptoms, including a cough that worsens at night due to increased pulmonary congestion when lying down.
- Foreign Body Aspiration: This is an emergency that requires immediate attention. A cough that starts suddenly, especially if accompanied by other symptoms like choking or difficulty breathing, could indicate an aspirated foreign body.
- Pneumonia: Bacterial or viral pneumonia can cause a cough that is worse at night, along with other symptoms like fever, difficulty breathing, and poor feeding in infants.
- Rare Diagnoses
- Cystic Fibrosis: A genetic disorder that affects the respiratory, digestive, and reproductive systems, causing persistent cough, among other symptoms. It's rare but should be considered in infants with recurrent or persistent respiratory symptoms.
- Anatomical Abnormalities (e.g., Tracheoesophageal Fistula, Laryngomalacia): These are congenital conditions that can affect the respiratory tract and cause coughing, especially when the infant is in a supine position.