[Modern approach to the classification and diagnosis of pneumonia].
New classification of pneumonia is pragmatic since a significant criterion is a condition in which an infection may develop: inflammations of the lungs in the home environment, immunodeficient patients, hospital infections, as a result of iatrogen complication, epidemics, etc. The principle of etiologic differentiation is reasonable when the therapy is indicated with certainty. Due to the difficulties in isolation and identification of sputum as well as the disappearance of the agent on onset of treatment because of specific therapy, the pathogenetic evolution and morphologic definition of the process is of great importance in the diagnostics and classification of pneumonia. In most patients the pneumonia has a clear course and the diagnosis is mostly established either by epidemiologic and clinical finding, laboratory testing and radiographically or by the response on empiric therapy. In some cases the invasive methods of diagnostics should be applied (BAL, transtracheal biopsy) in order to avoid false positive findings from the upper respiratory tract.