To investigate exposure to nonsteroidal antiinflammatory drugs (NSAIDs) during outpatient management at the early stage of community-acquired pneumonia (CAP) requiring hospital consultation. Non-interventional observational study.

Recent data suggests that such exposure to NSAIDs is associated with delay in CAP diagnosis and antibiotic prescription that influence CAP presention and outcome. The investigators' working hypothesis is that NSAIDs use may mask initial symptoms and delay antimicrobial therapy, thus predisposing to worse outcomes. All patients presenting at one of the three following locations (emergency department, ICU or pneumology ward) with a suspicion of community-acquired pneumonia will be screened for eligibility. Exposure or not to NSAIDs will be investigated. Clinical, biological and radioloigcal features and outcome of CAP will be compared with respect to NSAIDs exposure.

Inclusion Criteria: at least two among the following signs

• temperature > 37.8 °C
• respiratory rate > 25/min
• heat rate > 100/min
• cough
• expectoration
• chest pain
• crackles upon lung auscultation

and new infiltrate on the chest x-ray

Exclusion Criteria:

• ongoing pregnancy
• sickle cell disease
• tracheostomy
• long term oxygen therapy
• cystic fibrosis or bronchiectasis
• neutropenia (< 500 cells/mm3)
• ongoing solid or hematologic cancer or anticancerous chemotherapy
• HIV infection
• liver cirrhosis
• long term corticosteroid treatment (20mg per day equivalent prednisone for more than 15 days)
• preexisting treatment with NSAIDs for more than 15 days
• hospital admission for more than 48hours
• aspiration pneumonia

all adult patient presenting either to the emergency department or admitted directly to the ICU or the pneumology ward with a suspicion of CAP will be screened