What is Pediatric Bronchiolitis?
Bronchiolitis is a condition where the small airways in the lungs, known as bronchioles, get inflamed typically due to a sudden viral sickness. This condition is the leading infection of the lower part of the respiratory system in children who are less than 2 years old. It can cause problems with breathing that can affect the child’s ability to eat properly and result in frequent visits to the doctor or even hospital admissions. In fact, bronchiolitis has become one of the top reasons for children under the age of 2 to be hospitalized, especially during winter.
What Causes Pediatric Bronchiolitis?
The most common cause of acute bronchiolitis, or inflammation of the small tubes in the lungs, in children is a virus called the respiratory syncytial virus (RSV). RSV is a specific type of virus that has a protective outer layer and contains a single strand of genetic material.
Other viruses such as adenovirus, human metapneumovirus, influenza, and parainfluenza, can also cause this condition.
When adenovirus is detected, medical professionals can often use this information to further investigate the cause. That’s because adenovirus usually results in a high fever that lasts for an extended period of time.
Human metapneumovirus is not regularly tested for, but should be considered if the patient doesn’t test positive for RSV, yet has symptoms that suggest a similar infection. Patients who test positive for influenza may benefit from receiving antiviral treatment.
Risk Factors and Frequency for Pediatric Bronchiolitis
In colder regions, RSV-related bronchiolitis outbreaks typically happen in winter and early spring, peaking in January. Several risk factors increase the likelihood of contracting this illness. These include being born prematurely, chronic lung disease, complex heart conditions present from birth, a compromised immune system, infancy (under three months old), and other long-term health conditions. Something as everyday as exposure to smoke from a mother’s cigarette can worsen bronchiolitis caused by RSV in babies. Research has even linked this smoke exposure to higher rates of hospitalization in children. Diagnosing viral bronchiolitis, including identifying the specific virus, has become more accurate thanks to molecular tests. A large majority (80%) of bronchiolitis cases are due to respiratory syncytial virus (RSV).
Around the house, allergens such as dust mites, pets, and cockroaches can also trigger bronchiolitis in infants. Additionally, a recent research study found that infants who wheeze because of RSV bronchiolitis are more likely to develop asthma at an early age.
- RSV-related bronchiolitis outbreaks are common in winter and early spring, particularly in January, in colder regions.
- Risk factors include premature birth, chronic lung disease, complex congenital heart disease, weakened immune system, being under three months old, and existing chronic diseases.
- Exposure to a mother’s cigarette smoke can worsen RSV bronchiolitis and increase the likelihood of hospitalization in children.
- Molecular tests have enhanced the ability to accurately diagnose viral bronchiolitis and identify the specific virus, with RSV being responsible for 80% of cases.
- Allergens commonly found inside homes such as dust mites, pets, and cockroaches can also trigger the illness in babies.
- There is a higher chance for infants who wheeze due to RSV bronchiolitis to develop early-onset asthma.
Signs and Symptoms of Pediatric Bronchiolitis
The disease usually starts off with symptoms such as a runny nose, stuffed-up sinuses, loss of appetite, and a cough that may last for about 3 days. As the illness worsens, an excessively rapid breathing rate, wheezing, and difficulty in breathing due to the use of additional chest muscles can develop. Over time, grunting noises, flaring nostrils and a bluish skin color due to low oxygen levels in the blood may be observed, possibly leading to respiratory failure. As the disease can become serious, children, especially very young infants, should be monitored closely. Sometimes, a fever may occur. If this happens, it might be necessary to check the urine to rule out a urinary infection, particularly in uncircumcised boys.
- A runny nose
- Nasal congestion
- A decreased appetite
- A cough that lasts around 3 days
- Rapid breathing rate
- Difficulty in breathing
- Wheezing
- Grunting sounds
- Nostril flaring
- A bluish skin color (cyanosis)
- Potential respiratory failure
- Close monitoring, particularly for younger infants
- Potential fever
- Possibility of urinary tests to rule out urinary tract infection especially in uncircumcised males
Testing for Pediatric Bronchiolitis
Bronchiolitis is diagnosed primarily by observing the symptoms a patient has. Identifying this illness and figuring out how severe it is involves understanding the patient’s current health situation and the signs of illness they’re showing.
For patients suspected to have bronchiolitis, doctors will often test to see if a virus caused the illness. Commercially available tests can quickly identify these viruses by looking for viral “markers” in a sample taken from the patient’s nose or throat. Knowing the specifics of the virus can help doctors decide on the best treatment and manage the patient’s illness more effectively. It also helps in arranging the hospitalization of patients, keeping those with similar conditions together and isolated from others to prevent the spread of the virus.
However, a chest x-ray isn’t usually required since the findings are often nonspecific. It might show inflamed lungs, some markings in lung tissues, and thickening around the tiny airways in the lungs, but these findings alone aren’t enough to confirm bronchiolitis.
Treatment Options for Pediatric Bronchiolitis
The treatment for bronchiolitis focuses on easing symptoms and making sure the patient is comfortable. This could include action such as keeping the patient well hydrated, extracting any secretions from the upper airway, and careful monitoring for breathing difficulties that could require a breathing tube and ventilation machine. Some patients find relief through the inhalation of a salty mist, known as hypertonic saline nebulizations.
However, the use of supplemental oxygen isn’t always needed unless the oxygen levels in the blood consistently drop below 90%. Likewise, the use of continuous pulse oximetry, which measures oxygen levels in the blood, is not typically suggested as it could result in a longer hospital stay. If a patient runs a fever, it could be managed with fever-reducing medication.
Concerning the use of medication, bronchodilators, which help open up the airways, have not been shown to reduce the number of days a patient is symptomatic, the likelihood of being admitted to the hospital, or the duration of their stay. Hence, trials on bronchodilators are no longer recommended. Other medications like systemic steroids and racemic epinephrine, which reduces swelling in the throat, are also not advised.
Antibiotics, which are used to treat bacterial infections, should only be used if the patient has another infection along with bronchiolitis.
For patients who have tested positive for influenza A, a specific antiviral medication called oseltamivir can be beneficial. It works best if it’s administered within the first two days of the illness.
A medication named palivizumab was developed to prevent bronchiolitis caused by a Respiratory Syncytial Virus (RSV) in patients who are particularly at risk. The American Academy of Pediatrics (AAP) has serious criteria for qualifying patients for palivizumab. These patients could include babies born prematurely who are less than one year old during RSV season, patients with chronic lung disease or serious congenital heart disease, children with pulmonary disorders or neuromuscular disorders that interfere with clearing the airway, and patients with certain genetic diseases.
Each patient’s treatment for bronchiolitis will largely depend on their individual symptoms and general health condition.
What else can Pediatric Bronchiolitis be?
When a doctor is trying to figure out a diagnosis, they consider several other conditions that may be causing the symptoms. For this case, the doctor might consider:
- Gastroesophageal reflux disease (GERD), which is a chronic condition where stomach acid flows back into the esophagus.
- Congenital malformations, which are structural problems that occur at birth.
- Asthma, a condition that causes the airways in the lungs to swell and narrow, leading to wheezing, shortness of breath, chest tightness, and coughing.
- Aspiration of a foreign body, which happens when something a person swallowed gets stuck in their airways or lungs.
What to expect with Pediatric Bronchiolitis
Research has shown a possible link between bronchiolitis and an elevated risk of getting asthma later. However, it’s important to note that only a small number of children who experience bronchiolitis go on to develop asthma. The likelihood of developing asthma seems to be higher for those who frequently experience wheezing, or have a family history of asthma, allergies, or atopic dermatitis (a type of skin inflammation often seen in people with allergies).
