[A "difficult" pneumonia: problems of differential diagnosis]

There is a significant number of diseases that occur in the guise of community-acquired pneumonia (CAP), so the progressive course, slowly allowed or unresolved CAP search for an alternative disease becomes crucial. In more than 20% of patients with the syndrome of "protracted" pneumonia alternative diagnosis are established. List of the main pathological processes occurring under the guise of pneumonia include: infiltrative pulmonary tuberculosis, acute interstitial pneumonia, acute eosinophilic pneumonia, thromboembolism, pulmonary artery branches, systemic vasculitis, and a number. of other lung diseases. This publication attempts to organize a brief series of problems that practicing physicians often face in the management of patients with "difficult" pneumonia.