Breath Tests for Infection in Sick Children

Lung infections are very common in all children and do not usually cause them to become too unwell, although occasionally they do lead to an admission to hospital with pneumonia. The situation is different if the child has damaged lungs or an abnormal immune system. In these situations otherwise harmless organisms can cause life-threatening disease. When this happens the best approach is to find out what germ is causing the trouble and treat it with the best antibiotics available. Unfortunately the best tests we have available now are sometimes inaccurate or require unpleasant investigations such as bronchoscopy (lung washout) or removing pieces of the lung surgically to find out what is going on.

These infections are particularly important in diseases such as cystic fibrosis and leukaemia.  In cystic fibrosis the commonest germ to damage the lungs is pseudomonas which grows in thick gooey blobs and clogs up the small airways. This infects almost every person with cystic fibrosis and causes severe lung damage. In leukaemia the most hazardous organisms are fungi, such as those that grow on stale food. The infections are uncommon but usually fatal unless diagnosed very early. 

What are your research objectives?

The main objective is to find tests that work well but do not cause pain or discomfort and do not worry children. The test is actually rather fun to do.  If it works the tests can be done frequently allowing an early diagnosis to be made which should translate into much better outcomes.

How will you conduct your research?

The research has both a laboratory part and a human part. In the laboratory we are searching for the best gases to use as markers for particular germs, while in the human trials we will want to find out how well the markers we already know about will work. In this case children will be asked to give us breath samples so we can compare the results with other more standard tests.

Are there others in your field in new Zealand or globally conducting similar research?

Breath analysis for detecting lung infections is a highly specialised field of research with a very small number of researchers worldwide working on this approach to diagnosis. Other forms of breath testing are already being used to help treat asthma and detect drunk drivers and this is a new application of this basic idea.

What is innovative about the approach you are taking? 

Our team has developed the idea that when organisms are growing in the lung they will produce trace amounts of gases not produced by people that can be used to identify the germ. This requires very sensitive new technology (gas chromatography mass spectrometry). A fungus is the first organism we have promising results from. Most people know that a musty smell in a damp room is often caused by fungi growing in the area. We have found out what some of the substances are that give that smell and that very low amounts of these can be detected in exhaled breath. There are strong clues that other organisms such as pseudomonas may also be detectable by this method.

If you achieve your objectives what will that mean to those suffering from the disease or to the knowledge advancement of this disease?

 If we are successful we expect that children suffering from severe lung infections, associated with cystic fibrosis, can be treated more effectively and they will find the whole management of their illness much less demanding. We want to minimise the burden the whole family and health care team experiences when looking after sick children with prolonged severe illness.

Is there an international or national collaboration on your research project?

The research is collaboration between researchers at the University of Otago’s Christchurch School of Medicine and a scientist at Canesis Networks Ltd in Lincoln.

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