Stenotrophomonas maltophilia is a multi-resistant Gram-negative bacillus and is an opportunistic pathogen. Stenotrophomonas maltophilia infections are associated with a significant morbidity and mortality, particularly in immunocompromised patients. The mortality of infections (bacteremia, pneumonia) related to Stenotrophomonas maltophilia is variable and is estimated between 21 and 69%. Stenotrophomonas maltophilia pneumopathies have been mainly described in patients hospitalized in intensive care and benefiting from mechanical ventilation. The existence of immunosuppression seems to be a risk factor for the transition from Stenotrophomonas maltophilia pulmonary colonization to Stenotrophomonas maltophilia pulmonary infection. The reference treatment for Stenotrophomonas maltophilia-associated pneumonia is the combination of trimethoprim and sulfamthoxazole, a molecule that lung transplant patients routinely receive as a preventive treatment for Pneumocysitis jirovecii infection. There is no consensus on the value of routine dual-antibiotic therapy, and it varies from one center to another and from one country to another.

The main objective is to compare the clinical-microbiological evolution of lung transplant patients treated for Stenotrophomonas maltophilia pneumopathy according to the prescription of a mono- or bi-antibiotherapy.

The secondary objective is to evaluate the resistance rate of Stenotrophomonas maltophilia strains isolated from respiratory samples according to the anti-pneumocystis prophylactic molecule received by the patient.

Inclusion Criteria:

• Patient whose age ≥ 18 years
• Patient who has received a lung (mono or bi-pulmonary) or heart-lung transplant
• Patient with documented pneumopathy (clinico-radiological definition) (positive respiratory specimen for Stenotrophomonas maltophilia)
• French speaking patient

Exclusion Criteria:

• Patient under guardianship or curatorship
• Patient deprived of liberty
• Patient under court protection
• Patient objecting to the use of his data for this research

Patients managed for Stenotrophomonas maltophilia pneumonia following a lung or heart-lung transplant between 01/01/2011 and 01/01/2021