[Rational radiological diagnostics of pneumonia].

As one of the most common infectious diseases pneumonia is associated with a high morbidity and mortality. A rapid and rational diagnostic work-up is crucial to improve patient prognosis and outcome. The diagnosis of pneumonia requires the detection of pulmonary infiltrates; therefore, radiological methods are a key part of the diagnostic algorithm to demonstrate the presence of infiltrates and to confirm the diagnosis. The accepted standard method is chest X-ray at two levels, posteroanterior (PA) and lateral radiographs. Computed tomography is mainly used for immunocompromised patients, patients with pre-existing structural lung disease, therapy refractory pneumonia and in the differential diagnosis of suspected underlying diseases, such as pulmonary embolism or malignancy. Increasing evidence suggests that lung ultrasound is a promising, precise technology which is readily available and with no irradiation of patient.