Volatile Organic Compounds as Markers of Acute Rejection in Lung Transplant

Prospective single-center study. A single visit, no follow-up. The visit will take place before or within five days from date of transbronchial biopsies (BTB). It will include a noninvasive collection of exhaled breath for VOC analysis. VOC analysis will be conducted using two types of devices: "electronic nose" and mass spectrometry.

200 bi-lung transplanted patients will be enrolled and divided into two groups.

* Group A, Acute rejection: 100 patients. Diagnosis of acute rejection retained on transbronchial biopsies or functional anomalies with the necessity of modifying the immunosuppressive regimen.
* Group B, control: 100 patients. Patients without respiratory functional abnormality and normal transbronchial biopsy.

VOC, detected by electronic nose and identified by mass spectrometry, will be compared between patients with a confirmed diagnosis of acute rejection (group A) and patients without rejection (control group B)

The duration of participation of each patient is 1 day. The duration of the inclusion period is estimated at 54 months from the first inclusion. The expected total duration of the research is 54 months

• eNose (electronic nose) (Device): Collection of exhaled breath for an immediate analysis by electronic nose
• Spectrometry (Device): Collection of exhaled breath for an immediate analysis by mass spectrometry

Primary outcomes

• Volatile Organic Compounds by electronic nose (eNose) [1 day]: Comparison of Volatile Organic Compounds profile detected by electronic nose between lung transplant patients patients with a confirmed diagnosis of acute rejection and patients without rejection

Secondary outcomes

• Volatile Organic Compounds profile [1 day]: Comparison of Volatile Organic Compounds profile identified by mass spectrometry electronic nose between lung transplant patients with a confirmed diagnosis of acute rejection and patients without rejection
• Acute rejection diagnosis [1 day]: Comparison of discriminative capacity for diagnosis of acute rejection between the VOC analysis methods: electronic nose versus mass spectrometry.
• Volatile Organic Compounds by spectrometry [1 day]: Determining distinct exhaled VOC profiles associated with each type of acute rejection: cellular rejection, humoral rejection or functional rejection

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* Bi-pulmonary transplant patient
* Acute rejection group: Patients with transbronchial biopsies performed as part of their usual follow-up or for functional abnormality ; Diagnosis of acute rejection retained on the following arguments: histological lesions of cellular rejection or histological lesions of humoral rejection or normal histology but diagnosis of "functional rejection" retained and immunosuppressive treatment indicated
* Control group: Patients benefiting from systematically programmed transbronchial biopsies as part of post-transplant follow-up with normal histology and absence of functional respiratory abnormality

Exclusion Criteria:

* Patient unable to realize a vital capacity measure
* Neoplasia currently treated
* Unresolved acute bronchial complication (stenosis or dehiscence)
* Immunosuppressive treatment of acute rejection already begun
* Patient who has already participated in the protocol and already included in one of the two study groups

• Jean-Louis Couderc, MD-PhD, Study chair, Pneumologie Hopital Foch
• Antoine Roux, Principal investigator, Pneumologie Hopital Foch
• Hélène Salvator, MD, Study chair, Pneumologie Hopital Foch
• Philippe Devillier, MD-PhD, Study chair, UPRES EA 220 Hopital Foch