The aim of this study is to develop a safe and effective technique to take sample for lower respiratory tract cultures easy to perform in conditions of acute respiratory failure and spontaneous ventilation for patients admitted in intensive care unit for acute infectious pneumonia and non intubated. The investigators perform sample collection with a mini bronchoalveolar lavage catheter introduced by nasotracheal way through a suction catheter. The purpose of the study is to assess the microbiological diagnostic capacity of this new technique.

At the moment we lack an effective and safe technique to obtain lower respiratory tract cultures for patient with mild serious infectious pneumonia admitted in intensive care unit and non intubated. Invasive procedure may worsen respiratory distress and non invasive procedure such expectorated sputum culture is not enough effective. The purpose of the study is to assess the microbiological diagnosis capacity of a new technique for taking samples from the lower respiratory tract: mini bronchoalveolar lavage performed by naso tracheal way through a suction catheter.Each consecutive patient admitted in intensive care unit for a community acquired or nosocomial pneumonia and not requiring intubation and mechanical ventilation will be included. Written informed consent by patient himself will be required. For each patient, after the introduction of a suction catheter, an endotracheal aspiration will be performed. Then, the mini bronchoalveolar lavage will be performed through the suction catheter with a specific catheter.The whole time of the procedure is about ten minutes.Expectorated sputum will also be ordered for each patient.This study is a pilot and prospective study.

Inclusion Criteria:

• Age over 18
• Radiological diagnosis of pneumonia (community acquired or nosocomial)
• No microbiological diagnosis known
• Indication for culture of lower respiratory tract
• Admission in intensive care unit required

Exclusion Criteria:

• Age lower than 18
• Bronchospasm
• Coagulopathy ( Platelets count below 100 000/mm3, prothrombin time less than 50%, activated partial thromboplastin time ratio higher than 2)
• Intubation with mechanical ventilation
• Known microbiological diagnosis
• Incapacity for consenting himself to the study