Bronchiolitis obliterans (BO) is a rare chronic lung disease. After an injury to the lungs, the smallest airways, the bronchioles, become inflamed and then scar, narrowing or closing up. Air moves less freely, especially when breathing out, and the damage is usually permanent.
It should not be confused with bronchiolitis in infants, which is very common every winter and usually clears in a few days. Bronchiolitis obliterans is a rare and lasting complication of it.
This is the childhood form, called post-infectious (PIBO). It follows a severe respiratory infection, most often adenovirus, sometimes mycoplasma or other viruses. This is Gabriel’s disease.
It is then a form of chronic rejection of the graft, known as bronchiolitis obliterans syndrome.
It can appear after a stem cell transplant, as the lung form of graft-versus-host disease.
More rarely, it can follow the inhalation of toxic substances or come with certain autoimmune diseases.
In children, doctors think of it when, several weeks after a serious respiratory infection, the following persist:
These signs look like asthma, and the disease is often mistaken for asthma at first. The difference: usual asthma treatments bring little relief. Time to diagnosis matters, because early care may help limit lasting damage.
Diagnosis is based on the child’s history, clinical examination, a chest CT scan (showing a typical “mosaic” pattern and air trapped in the lungs) and, when age allows, lung function tests. A lung biopsy is rarely needed. Follow-up is led by a pulmonologist, a paediatric one for children.
There is currently no treatment that cures bronchiolitis obliterans. Care aims to calm inflammation, protect the lungs and support the child’s growth. Depending on the case, the medical team may offer corticosteroids, certain long-term antibiotics used for their anti-inflammatory effect, inhaled treatments, chest physiotherapy, oxygen or non-invasive ventilation, nutritional support and a complete vaccination schedule.
In young children there is a reason for hope: the lungs keep growing for years, and in some children symptoms ease as they grow, even though the damage to the bronchioles remains. The most severe forms, however, can progress to chronic respiratory failure, which is why regular follow-up matters.
Day to day, the main challenge is to avoid respiratory infections, which can worsen the damage: hand hygiene, masks during epidemics, up-to-date vaccinations for the child and those around them, no smoking at home. This constant vigilance weighs on families, and the isolation that comes with it is one of the reasons the association exists.
No, there is currently no treatment that cures it: the damage to the bronchioles is usually permanent. However, appropriate care helps stabilise the disease, and in some young children symptoms ease as their lungs grow.
Bronchiolitis is a very common viral infection in infants that usually clears within days. Bronchiolitis obliterans is a rare chronic disease: after a severe infection, the small airways scar and narrow, and breathing difficulties persist.
In the vast majority of cases, no: the baby recovers completely. Lasting damage is rare and mostly follows a very severe infection, for example with adenovirus. If coughing, wheezing or breathlessness persist for several weeks after the infection, talk to your paediatrician.
No. It is a scar left in the lungs, not an infection. Respiratory viruses are what is contagious, and an affected child needs to be protected from them, because a new infection can worsen the damage.
BO Community, the platform created by the association, offers complete guides, a watch of scientific publications summarised in plain language, family stories and a directory of specialists.
This page is general information written by parents. It does not replace medical advice. For any question about your child’s health, talk to your paediatrician or pulmonologist.
This page draws in particular on the following publications:
