Differential Diagnosis for Bronchiolitis vs Reactive Airway Disease in a 7-Month-Old
Single Most Likely Diagnosis
- Bronchiolitis: This is the most likely diagnosis in a 7-month-old presenting with respiratory symptoms, as bronchiolitis is a common lower respiratory tract infection in infants, typically caused by the respiratory syncytial virus (RSV).
Other Likely Diagnoses
- Reactive Airway Disease (RAD): Also known as asthma, RAD is a condition characterized by episodic airway obstruction, which could be a consideration in this age group, especially if there's a history of similar episodes or atopic conditions.
- Viral Pneumonia: Other viral pathogens can cause pneumonia in infants, which might present similarly to bronchiolitis, making it an important differential diagnosis.
Do Not Miss Diagnoses
- Congenital Heart Disease: Although less common, undiagnosed congenital heart disease can present with respiratory symptoms due to pulmonary congestion or other complications, making it crucial not to miss.
- Foreign Body Aspiration: This is an emergency that can cause sudden onset of respiratory symptoms and must be considered, especially if the history suggests a possible aspiration event.
- Pertussis (Whooping Cough): Given the potential for severe disease in infants and the fact that vaccination may not be fully effective at this age, pertussis is a critical diagnosis not to miss.
Rare Diagnoses
- Cystic Fibrosis: While rare, cystic fibrosis can present with recurrent respiratory infections and should be considered in infants with persistent or severe respiratory symptoms.
- Primary Ciliary Dyskinesia: A rare genetic disorder affecting the motility of cilia, leading to recurrent respiratory infections, which could be a consideration in infants with persistent symptoms.
- Immunodeficiency: Certain immunodeficiencies can increase the susceptibility to severe or recurrent infections, making this a rare but important differential diagnosis in infants with unusual or severe presentations of common infections.