Aim/goal of project

Hypothesis

This is a double blinded placebo-controlled randomized controlled trial to assess the efficacy of a single dose of Azithromycin (30mg/kg) in 92 infants < 18 months to

a) Improve the clinical course of moderate to severe bronchiolitis (assessed by supplemented oxygen requirement and length of hospital stay).
b)  Reduce the risk of further respiratory illness within 6 months of this bronchiolitis episode.
c)  Profile the immunopathology of bronchiolitis in the presence and absence of co-existing respiratory infections.
 
Background
Bronchiolitis remains the most common acute lower respiratory tract infection (ALRTI) in infants. It is primarily caused by a viral infection called Respiratory Syncytial Virus (RSV) although other viruses may also contribute. Bronchiolitis is characterised by inflammation of the airways, increased mucous production and necrosis of epithelial tissue. In paediatrics, bronchiolitis is a clinical diagnosis characterised by tachypnoea, wheeze and/or crepitations in infants following a preceding upper respiratory illness. Most cases can be treated at home; however in some cases hospitalisation may be required for supportive therapy (such as oxygen and fluid therapy).
Most cases can be treated at home; however in some cases hospitalisation may be required for supportive therapy (such as oxygen and fluid therapy).

We have found that Northern Territory (NT) Indigenous infants present to hospital more often and with more severe bronchiolitis than non Indigenous infants. These infants are at greater risk of developing longer term respiratory problems including chronic suppurative lung disease or bronchiectasis. Bronchiolitis in NT Indigenous children is complicated by the known early colonisation of the nasopharynx by bacterial pathogens, notably Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pneumoniae.

A class of antibiotics called the macrolides like Azithromycin have been widely used in the Northern Territory for bronchiectasis, trachoma and sexually transmitted diseases. Azithromycin has anti inflammatory and bacterial properties. It has a longer half life and better tissue penetration than other macrolides thus requiring a much shorter treatment regime. Once weekly dosing has been shown to be sufficient for tissue effects lasting over a week. Any intervention that is efficacious in reducing the severity of bronchiolitis and or readmission for bronchiolitis in particular for Indigenous children would be beneficial in both short and long term outcomes.

Interesting information
We have enrolled 82 of the 92 required from both Royal Darwin Hospital and The Townsville Hospital.

Links/newsletters

Bronchiolitis Flip Chart-Citation

www.LungInfoNet.org.au