The paper discusses a case of 50-year-old male admitted to the hospital with symptoms of respiratory failure. The patient had previously been treated for pneumonia. After the admission, control-assisted ventilation was introduced and a swab from endotracheal tube was taken for microbiological examination, as well as pefloxacin, dexamethasone, Ambroxol and heparin treatment was administered. Patients condition improved. After several days respiratory failure intensified, requiring repeated artificial ventilation. According to the obtained antibiogram, Tienam was administered with favourable results. During the therapy with Tienam no side-effects were observed. Based on chest X-ray examination and data from interview, infection of multiple congenital bronchogenic cysts was diagnosed.