Bronchiectasis and bacterial bronchitis in children explained

Bronchiectasis (pronounced bron-kee-ek-tuh-sis) in children is a long-term condition where the airways become swollen and widened. Excess mucus pools in these widened airways, which significantly increases the risk of lung infections. 

It can lead to chest deformities, reduced lung function, pressure on the heart, poor growth and swelling of the fingertips (clubbing). 

Risk factors for bronchiectasis

Any respiratory problem that is left untreated or any condition that makes it difficult to clear mucus (eg due to nerve or muscle problems) can lead to bronchiectasis.

Risk factors, therefore, include asthma, cystic fibrosis, primary ciliary dyskinesia, cerebral palsy, spinal muscular atrophy, immunodeficiency diseases and protracted bacterial bronchitis.

Protracted bacterial bronchitis has only been recognised in the last 10–15 years as a common cause of bronchiectasis.

What is protracted bacterial bronchitis?

Protracted bacterial bronchitis is a long-lasting bacterial infection of the airways. It is usually triggered by a viral infection, such as a cold. This causes excess mucus production in the airways. Most children can cough up this mucus but in those who can’t, a persistent wet cough develops ie a wet cough that lasts over two to four weeks with no symptom-free intervals. This creates the ideal environment for bacteria to infect the mucus, leading to protracted bacterial bronchitis.

Once protracted bacterial bronchitis takes hold, the airways continuously produce chemicals that promote inflammation. Over time, this leads to swelling of the airways ie bronchiectasis, which can’t be reversed. It is, therefore, vital to diagnose and treat bacterial bronchitis early.

Risk factors for bacterial bronchitis

Children with respiratory conditions (eg asthma, cystic fibrosis, primary ciliary dyskinesia) and structural problems with their airways are at greater risk of bacterial bronchitis.

A common structural airway problem identified in children with bacterial bronchitis is a floppy windpipe (airway malacia). We are all born with a floppy windpipe, which grows and stiffens as we get older. However, in children with airway malacia, the windpipe is too floppy.

Consequently, when they cough, part of their windpipe temporarily collapses, preventing mucus from being coughed up. This results in a persistent wet cough as the airways keep trying to clear the trapped mucus, and increases the risk of bacterial infections.

Symptoms of bacterial bronchitis

Children with bacterial bronchitis can have a wet cough for two weeks or more but otherwise appear well ie they do not have a fever or loss of appetite.

They may, also, develop a wheeze, which can be mistaken for asthma. However, the wheeze associated with bacterial bronchitis is monophonic ie has one pitch, while the wheeze that occurs in asthma is polyphonic ie has multiple pitches.

The main treatment for asthma is the application of a bronchodilator drug. This relaxes the muscles around the airways and consequently makes the airways less tense. However, if your child has protracted bacterial bronchitis caused by a floppy airway, this can worsen their symptoms as it makes the already floppy airway even floppier.

Investigating bacterial bronchitis

If your child has a wet cough for more than two weeks, it’s important to take them to see your GP. Based on their symptoms and medical history, if bacterial bronchitis is suspected, your doctor may recommend a flexible fibreoptic bronchoscopy. This will be performed at a specialist centre by a doctor who is specially trained in paediatric respiratory medicine.

A thin, stethoscope-like, bendy tube with a camera and a light on the end (a bronchoscope) will be passed into your child’s airways via their mouth. This takes around 30 minutes and is always performed under general anaesthetic in children. In the NHS it can be performed in both children and babies weighing one kilogram or more. In private healthcare, it can only be performed in children aged one and above who weigh at least 10 kilograms.

During a bronchoscopy, your respiratory specialist doctor can collect a sample of mucus to be tested for infections and can also investigate the underlying cause of bacterial bronchitis, such as floppy airways, asthma, gastro-oesophageal reflux disease (GORD) or compression of the airways from structures outside the windpipe.

Treating bacterial bronchitis

Bacterial bronchitis is treated with a two to eight week course of antibiotics. As the reach of antibiotics into the airways is not good, a short course of antibiotics is not enough to resolve the infection.

Left untreated bacterial bronchitis can lead to bronchiectasis.

Treating bronchiectasis

If bronchiectasis is very localised and other approaches to managing symptoms is not helpful, the affected area of the airways can be removed via surgery. However, in most cases, multiple areas are affected. As bronchiectasis causes irreversible lung damage, treatment is lifelong and focuses on managing symptoms and the underlying processes.

This involves taking mucolytics (ie 3% or 7% hypertonic saline) to thin out the mucus. In children with cystic fibrosis, dornase alfa (an enzyme solution that is inhaled and helps break down mucus) may be prescribed too.

Management also involves special chest physiotherapy using a variety of techniques, including the use of a positive expiratory pressure (PEP) device in children with airway floppiness, and regular prophylactic antibiotics ie antibiotics to prevent bacterial infection.

As bronchiectasis in children can affect their growth, nutritional support and advice are also needed.