Differential Diagnosis for a 2 Years & 3 Months Old Child with Persistent Cough
- Single Most Likely Diagnosis
- Viral-induced cough or upper respiratory tract infection: The child's symptoms of a persistent cough that started without fever, difficulty breathing, or changes in feeding and sleeping patterns, and was exacerbated at night, are consistent with a viral upper respiratory tract infection. The lack of response to Phenylephrine syrup and the presence of low-grade fever that was relieved by Paracetamol further support this diagnosis.
- Other Likely Diagnoses
- Asthma: Given the family history of bronchial asthma (paternal grandfather) and the child's symptoms of a persistent cough that worsens at night, asthma should be considered. However, the absence of wheezing or other respiratory symptoms makes this less likely.
- Allergic rhinitis: The child's history of allergic reactions (to Amoxicillin) and the presence of a persistent cough without other symptoms could suggest allergic rhinitis, especially if the cough is postnasal drip-induced.
- Pertussis (Whooping Cough): Although the child has had similar episodes before, the description of the cough being so bad that it makes him throw up could suggest pertussis, especially if the vaccination status is not up to date or if there's a possibility of vaccine failure.
- Do Not Miss Diagnoses
- Pneumonia: Although the child does not have fever, difficulty breathing, or adventitious sounds on lung exam, pneumonia can sometimes present atypically, especially in young children. It's crucial to consider this diagnosis due to its potential severity.
- Foreign body aspiration: The sudden onset of cough, especially if it's severe enough to induce vomiting, could be indicative of a foreign body in the airway. This is a medical emergency that requires immediate attention.
- Tuberculosis (TB): Given the aunt's history of chronic cough with blood-streaked sputum (diagnosis unknown), TB should be considered, especially if the family has been exposed to someone with TB or if they are from a high-prevalence area.
- Rare Diagnoses
- Cystic Fibrosis: This condition can present with recurrent respiratory infections and chronic cough. Although it's rare, it's an important consideration in a child with persistent respiratory symptoms.
- Immunodeficiency: A child with recurrent infections, including those presenting with cough, might have an underlying immunodeficiency. This would be more likely if the child has a history of severe or recurrent infections.
- Congenital anomalies of the airways: Conditions like tracheoesophageal fistula or laryngotracheal cleft could present with chronic cough, especially if associated with feeding difficulties or recurrent pneumonia.