Diagnosis of Croup
Diagnosis of croup is primarily clinical, meaning that it is based on a physical examination and the child’s medical history. Most cases of croup can be diagnosed by a doctor without the need for laboratory tests or imaging. The distinctive barking cough and stridor, along with a recent history of cold-like symptoms, are usually enough to confirm the diagnosis.
Clinical Assessment
During the consultation, the healthcare provider will:
Ask about symptom onset, duration, and severity
Listen to the child’s breathing for signs of stridor or wheezing
Observe for signs of respiratory distress, such as chest retractions or nasal flaring
Check for fever, hydration status, and general behaviour (alertness, irritability)
Stridor at rest and chest wall retractions often indicate moderate to severe croup, and these findings help determine the need for medical intervention.
Differential Diagnosis | Diagnosis of Croup
It is important to differentiate croup from other potentially serious conditions that may present with similar symptoms:
Epiglottitis: A medical emergency characterised by drooling, difficulty swallowing, and severe respiratory distress. Unlike croup, it presents with a quiet voice and no cough.
Bacterial tracheitis: Can follow a viral illness and leads to thick secretions, high fever, and worsening airway obstruction.
Foreign body aspiration: Sudden onset of coughing or stridor, particularly with no history of preceding illness.
Allergic reactions or anaphylaxis: May also cause upper airway swelling and require immediate treatment.
Imaging and Testing
In typical cases, no tests are necessary. However, in uncertain or severe cases, doctors may use:
Neck X-rays: To rule out epiglottitis or foreign bodies. Croup may show the “steeple sign”—a narrowing of the upper trachea.
Pulse oximetry: To monitor oxygen saturation in moderate to severe cases.
Viral swabs: Occasionally done to identify the causative virus, though this rarely changes treatment.
When to Refer
Referral to hospital or specialist care is required if:
The child has severe symptoms or is not responding to initial treatment
There is suspicion of an alternative diagnosis
Oxygen levels are persistently low
In conclusion, diagnosis of croup is based on physical signs and a history of recent viral illness. Most cases can be confidently diagnosed in a clinical setting without the need for invasive tests.
