[Diagnosis of community acquired pneumonia in adults].

In contrast with acute bronchitis, which is benign and very frequent, community acute pneumonia has to be considered as a serious illness with a mortality rate that can reach 10-15% in inpatients. In adult, pneumonia is usually due to bacteria and antibiotherapy is always required. Clinical diagnosis is based on presumption signs: fever, tachycardia, tachypnea, thoracic pain, localised rales and a global severity impression. A chest X-ray is required. The pathogens involved are usually Streptococcus pneumoniae or atypical organisms. In inpatients (severe pneumonia or presence of risk factors), other pathogens such as gram negative bacilli or anaerobes are possible. The accurate diagnosis is based on invasive methods, which are not justified in outpatients but indicated in severe pneumonia.