Coughing in infants is a common symptom that can be distressing for parents. While often a sign of a minor illness, it’s crucial to understand when a cough might indicate a more serious underlying condition. This guide provides an overview of the differential diagnosis of cough in infants, helping to identify potential causes and when further investigation is necessary.
For infants presenting with acute cough, especially alongside upper respiratory infection symptoms like a runny nose or mild fever, the most likely culprit is a viral infection. In these instances, and particularly if there are no red flag findings, extensive testing is usually not needed. However, if symptoms persist or worsen despite initial management, further evaluation becomes important.
Certain “red flag” findings necessitate prompt medical attention and specific diagnostic approaches. For example, infants exhibiting stridor, excessive drooling, fever, and marked anxiety should be immediately assessed for epiglottitis. This condition often requires evaluation in an operating room by a specialist prepared to secure the airway. If there is a suspicion of foreign body aspiration, chest radiography with inspiratory and expiratory views, or potentially a chest CT scan, is recommended to visualize any obstruction.
Chronic cough in infants also warrants specific investigations. Infants with risk factors for tuberculosis or those experiencing weight loss should undergo a chest radiograph and tuberculosis testing, such as a tuberculin skin test (PPD) or an interferon-gamma release assay. For infants with recurrent pneumonia, poor weight gain, or foul-smelling stools, cystic fibrosis should be considered, requiring a chest radiograph and sweat testing for diagnosis.
In cases where initial treatments are unsuccessful, further diagnostic steps may be needed. For instance, if allergic sinusitis is suspected and antihistamines fail to provide relief, a head CT scan might be necessary. Similarly, infants with suspected gastroesophageal reflux disease (GERD) whose symptoms do not improve with H2 blockers or proton pump inhibitors may require a pH or impedance probe study, or even endoscopy, to properly assess and manage their condition.
In summary, while many infant coughs are benign and self-limiting, a careful assessment for red flag symptoms and consideration of potential underlying conditions are essential for accurate differential diagnosis and appropriate management. Prompt evaluation and targeted testing, guided by clinical presentation and risk factors, ensure the best possible outcomes for infants presenting with cough.
