An electronic “nose” can accurately detect when a lung transplant is starting to fail with 86% accuracy, experts will hear today.
Research to be presented at the online European Respiratory Society International Congress today will reveal that using the device could enable doctors to spot early stage chronic allograft dysfunction (CLAD) so that appropriate treatments could be administered to prevent it worsening.
However, Ms Nynke Wijbenga, a PhD student and technical physician at Erasmus University Medical Centre, Rotterdam, The Netherlands, says more research is needed before the eNose could be used.
About 50% of lung transplant patients are diagnosed with chronic allograft dysfunction or chronic rejection within five years of the transplant and chronic rejection remains the most important cause of death after lung transplantation.
There are two types of chronic rejection: bronchitis obliterans syndrome (BOS) and restrictive allograft syndrome (RAS), and there is currently no treatment to reverse it.
It can take several months to diagnose CLAD as lung function is tested at each hospital check-up and it is measured against the best peak lung function achieved after the transplant.
If it drops to 80% or lower, further investigations are carried out. Chronic rejection can only be confirmed after these investigations and if the decline in lung function continues for three months.
Ms Wijbenga and her colleagues studied 91 lung transplant patients, aged between 35 and 73, at Erasmus MC between July and November 2020, using the eNose, which contains sensors to detect volatile organic compounds (VOCs), present in about one per cent of our exhaled breath.
When patients breathe out into the eNose, the sensors detect the pattern of VOCs in the breath and the correct the results to take account of the ambient air that has been inhaled.
The results are analysed using artificial intelligence and the “breathprint” can identify several lung diseases.
For the study, one eNose measurement was taken from each patient and their results were compared with diagnoses that the patients’ consultants had already made.
In 86% of cases, the eNose distinguished between the 68 patients who had stable lung transplants and the 23 patients who had CLAD.
“These results suggest that the eNose is a promising tool for detection of CLAD,” said Ms Wijbenga.
“However, more research is required before it can be used in the clinic. We need to assess whether repeated measurements in the same patients can provide more accurate diagnoses and even predict CLAD before it occurs. Also, we need to confirm our results in other groups of patients. Nonetheless, we aim to develop this as a technique for wide use across Europe.
“We hope that our further research will reveal whether eNose technology could distinguish between BOS and RAS. Additionally, we want to investigate if it could be used for other complications after lung transplantation, such as acute rejection and infection.”
Abstract no: OA2914: Nynke Wijbenga et al. Electronic nose for detecting chronic lung allograft dysfunction in lung transplant recipients. 7 September 2021.
Leave a Reply