How to Diagnose Bronchiolitis

Co-authored by Jurdy Dugdale, RN

Updated: September 4, 2019

Explore this Article Observing the Symptoms of Bronchiolitis Diagnosing Bronchiolitis Diagnosing Severe Bronchiolitis Article Summary Ask a Question Related Articles References

Bronchiolitis is an illness of the respiratory tract, caused by an infection in the bronchioles, which are passageways that allow air to enter the lungs. The illness can be tricky to diagnose, but the good news is that it’s relatively easy to cure. Bronchiolitis can affect anyone, but it is more common in infants, young children, the elderly, and individuals who are immune-deficient. If bronchiolitis is suspected, the sick individual should see a doctor immediately. If the case of bronchiolitis is difficult to diagnose, the doctor may need to perform an x-ray or a nasal swab.

Part 1
Observing the Symptoms of Bronchiolitis

  1. 1
    Watch for cold-like symptoms. Bronchiolitis often begins with symptoms that resemble those of the common cold or the flu. Although these symptoms progress as bronchiolitis worsens, the illness will be easier to cure if you catch the symptoms early on. Look for:[1]
    • A runny or stuffy nose.
    • A persistent cough.
    • A slight fever up to 102 °F (39 °C)[2]
  2. 2
    See if the symptoms worsen over 2 days. While the symptoms of bronchiolitis can be caused by several different illnesses, including cold or flu, the patient should see a doctor if symptoms worsen to get a proper diagnosis and treatment. Otherwise, their condition can continue to worsen.[3]
    • The individual's nose will become increasingly runny, their cough will become more noticeable, and the fever will rise.
  3. 3
    Observe if the person develops a wheezing cough. As the symptoms of bronchiolitis become more severe, the person's cough will worsen. The final breaths of the cough will also turn into a wheeze.[4] The person may also experience difficulty breathing.
    • The telltale wheeze will most often sound like a high-pitched squeaking sound when the person exhales. Wheezes are typically not noticeable when the person inhales. However, you may not hear the wheezing, especially if the congestion is severe. If you're worried this is the case, put your ear up to the person's chest to listen for wheezing.
    • If you have a sick child, you can check for trouble breathing by looking at the child's chest. Take off their shirt and watch the rise and fall of their chest as the child breathes. If the child is having trouble breathing, you will see the rib cage more clearly as the child inhales.
  4. 4
    Check your infant’s ears for infection. Infants with bronchiolitis often simultaneously develop an ear infection. [5] Watch your infant’s behavior to determine if they have an ear infection. Infants with ear infections will tug or scratch at their ears, or may have difficulty sleeping. You may also notice liquid draining from their infected ears.
    • The ear infection will likely make your infant cranky and irritable.

Part 2
Diagnosing Bronchiolitis

  1. 1
    Take the person to an urgent care center. As with any medical diagnosis, you’ll need a doctor to make a diagnosis and prescribe treatment. Take the person to an emergency care provider if their breathing has become strained or labored, or if their wheeze has worsened. Many urgent care centers are open 24 hours a day.[6]
    • Some emergency care centers prioritize children, so you may get immediate treatment.
    • You can call your doctor if you think you can get in that day. When speaking to the receptionist over the phone, explain that the situation is urgent and you’d like an appointment today. If that's not possible, visit an urgent care center immediately.
    • The doctor will be able to prescribe medication to help clear up the respiratory infection. They will also likely offer immediate nebulizing treatment to help the patient breathe better.
  2. 2
    Seek medical attention if the individual displays severe symptoms. With a serious infection, symptoms can quickly worsen. Don’t panic, but take them to an urgent care center immediately. They need to see a doctor, but their symptoms are still completely treatable. Even if the person doesn’t show strained or labored breathing, take them to the doctor promptly if they display any of these symptoms:[7]
    • Vomiting.
    • Fast, shallow breaths.
    • Refusing to eat, or breathing to fast to be able to eat.
    • Lethargic behavior.
  3. 3
    Describe the patient's behavior and medical history to the doctor. The doctor will need a full background to make a diagnosis. Describe the symptoms to the doctor, including how long they have been ill, how sever their cough is, and whether they’ve had a fever or ear infection. You can help the doctor further by answering their questions about the person's medical history.
    • For example, the doctor may want to know if they are frequently exposed to secondhand smoke, or if they are on any medications.[8]
  4. 4
    Agree to medical tests that the doctor advises. In some cases, the doctor won’t be able to diagnose bronchiolitis through observation alone. This is common, and no reason to worry. The doctor may ask to administer examinations that will allow them to image the lungs and to test for the presence of the RSV virus (which most commonly causes bronchiolitis). Tests include:
    • Chest x-rays.
    • Blood tests.
    • A nasal swab.
    • Pulse oximetry, in which a painless blood oxygen sensor is lightly clamped on a finger.

Part 3
Diagnosing Severe Bronchiolitis

  1. 1
    Call the doctor immediately if you note symptoms of severe bronchiolitis. Unlike most cases, severe bronchiolitis can be life-threatening, although it's still treatable. Infants with severe bronchiolitis will usually need to be treated in a nearby hospital, and may be kept overnight, depending on the severity of their infection. Infants at risk for severe bronchiolitis include those:[9]
    • Born prematurely.
    • Who have a chronic lung or heart disease.
    • Who have a weak immune system.
  2. 2
    Inspect the lips and skin for a blue tone or paleness. Blue skin and lips—a condition known as cyanosis—is a symptom of severe cases of bronchiolitis. Cyanosis indicates that the person's respiratory passages are so blocked that not enough oxygen is reaching their extremities. While cyanosis isn’t an emergency in itself, it needs to be treated by a doctor.[10]
    • On darker skin tones, lips and skin may look pale rather than blue.
    • Call a doctor immediately if you notice that the person's lips and skin are blue or pale. The person likely needs immediate medical care.
  3. 3
    Observe the person for pauses in their breathing. Long pauses between breaths—or periods of time when the person isn’t breathing at all—are signs of apnea. Apnea is a symptom of severe bronchiolitis and can be life threatening. If the person experiences apnea, reassure them and ask them to focus on their breathing. Then seek emergency care.[11]
    • Apnea occurs most frequently in infants who were born prematurely or who are less than 2 months old.
    • Seek emergency care if your child experiences apnea.

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    • The bronchioles of infants and young children are smaller than in teens and adults, and so become infected more easily. Children contract bronchiolitis most commonly before they turn 2, and often when they’re between 3 and 6 months.[12]
    • The symptoms of bronchiolitis can be difficult to tell apart from symptoms of the flu or the common cold. This similarity may lead your doctor to misdiagnoses your child’s bronchiolitis at first.[13]
    • Cases of bronchiolitis peak during the cold winter months.[14]
    • Infants with severe bronchiolitis sometimes experience severe respiratory failure. In this situation, doctors will insert a tube down the child’s trachea to allow the child to breathe easier.[15]

    Article SummaryX

    To diagnose bronchiolitis, look for symptoms that are similar to a cold or flu, like a stuffy nose, persistent cough, and slight fever. For symptoms that worsen over 2 days, see a doctor to get a proper diagnosis and treatment before the condition worsens. If your cough not only worsens but also becomes more of a wheezing sound, you should see your doctor as soon as possible. While your doctor may be able to diagnose bronchiolitis through observation alone, they may also suggest a chest x-ray, blood work, or nasal swab. For more tips from our Medical co-author, including how to diagnose severe bronchiolitis, keep reading!

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    Categories: Lung Health

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    Español: diagnosticar la bronquiolitis, Português: Diagnosticar Bronquiolite

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