Tests and diagnosis
By Mayo Clinic staffThe doctor will likely listen to your child's lungs with a stethoscope to check for wheezing and prolonged breathing out (exhaling). These may indicate obstructed airflow in the bronchioles. The doctor may consider specific risk factors for bronchiolitis as well.
Sometimes other tests are recommended, including:
- Chest X-ray. In severe or uncertain cases, your doctor may request that a chest X-ray be taken to visually check for any signs of pneumonia. Your doctor may also check for the presence of a foreign object, such as a peanut or small piece of plastic, that your baby or toddler may have inhaled.
- Mucus sample test. In addition, your doctor may collect a sample of mucus from your child — using a nasal pharyngeal swab or a suction catheter that's gently inserted into the nose — to test for the virus that may be causing the bronchiolitis.
- Blood tests. Occasionally, blood tests might be used to check your child's white blood cell count. An increase in white blood cells is usually a sign that your body is fighting an infection. A blood test can also determine whether the level of oxygen has decreased in your child's bloodstream. An alternative test for oxygen levels is an oximeter that fits over the finger. Oxygen is necessary to the functioning of the body's organs, including the brain.
Your doctor may also ask you about signs of dehydration, especially if your child has been refusing to drink or eat or has been vomiting. Signs of dehydration include sunken eyes, dry mouth and skin, sluggishness, and little or no urinary output.
- In: Mandell GL, et al. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 76th ed. Philadelphia, Pa.: Churchill Livingstone Elsevier; 2009. Accessed Aug. 5, 2010.
- Piedra PA. Bronchiolitis in infants and children: Clinical features and diagnosis. http://www.uptodate.com/home/index.html. Accessed Aug. 5, 2010.
- Watts KD, et al. Wheezing, bronchiolitis, and bronchitis. In: Kliegman RM, et al. Nelson Textbook of Pediatrics, 18th ed. Saunders Elsevier; 2007. Accessed Aug. 5, 2010.
- Everard ML. Acute bronchiolitis and croup. Pediatric Clinics of North America. 2009;56:119.
- Seiden JA, et al. Bronchiolitis: An evidence-based approach to management. Clinical Pediatric Emergency Medicine. 2009;10:75.
- Hoecker JL (expert opinion). Mayo Clinic, Rochester, Minn. Aug. 8, 2010.


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