Differential Diagnosis for a 14-month-old Female with Respiratory Symptoms
- Single most likely diagnosis:
- Viral upper respiratory tract infection (URTI): This is the most common cause of runny nose, cough, and decreased appetite in a child of this age group, especially in the absence of fever or other alarming symptoms. The presence of yellow phlegm can indicate a viral infection that has led to a secondary bacterial infection, but the primary cause is likely viral.
- Other Likely diagnoses:
- Allergic rhinitis: Could be considered if there's a history of allergies or if symptoms persist or recur, especially with exposure to specific allergens.
- Acute bronchiolitis: Although typically seen in younger infants, it could be a consideration, especially if the cough is more prominent and there are signs of respiratory distress.
- Sinusitis: Given the yellow phlegm, this could be a possibility, especially if symptoms persist beyond the expected duration for a viral URTI.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed):
- Pneumonia: Although the child does not have a fever, pneumonia can sometimes present without fever, especially in young children. The presence of a dry cough and decreased appetite warrants consideration of this diagnosis.
- Foreign body aspiration: This is a critical diagnosis to consider in any child with sudden onset of respiratory symptoms, as it can lead to severe complications if not promptly addressed.
- Pertussis (whooping cough): Especially if the cough is severe or has a characteristic whoop, this diagnosis should be considered, particularly if vaccination status is incomplete or unknown.
- Rare diagnoses:
- Cystic fibrosis: Should be considered if there are recurrent respiratory infections or if there's a family history, though it would be unusual for this to be the first presentation.
- Immunodeficiency: If the child has recurrent severe infections or fails to thrive, an immunodeficiency could be a rare underlying cause.
- Congenital anomalies of the respiratory tract: Though typically diagnosed earlier in life, some anomalies might not become apparent until later, especially if they are partial or less severe.