The paper presents the case of a 14-month-old child with a persistent respiratory distress with wheezing and diffuse crackles on chest auscultation. Symptoms appeared after a viral pneumonia caused by Adenovirus. The recent history, the clinical manifestations and the lung CT (Computed Tomography) scans, which showed a diffuse mosaic pattern, with air trapping, bronchiectasis and peribronchial inflammation, led to the diagnosis of Post-infectious Bronchiolitis Obliterans (PIBO). PIBO is a rare chronic paediatric pulmonary disease characterized by irreversible fibrotic narrowing of the small airways. It can present with a broad severity spectrum, and the evolution of this condition is not predictable in the single patient. Adenovirus is by far the most common cause of this lung pathology, and during the post Covid-19 pandemic an unprecedented rise in PIBO cases triggered by Adenovirus lower respiratory infections was observed. The treatment of PIBO is empirical, and a defined protocol does not exist yet. Therapeutic approaches range from nil to methylprednisolone pulse therapy, which would seem effective especially if performed early and if peribronchitis is found on imaging. Some studies evaluated the administration of intravenous immunoglobulins, while in more advanced cases showing fibrotic transformation of the parenchyma, the use of antifibrotic drugs (hydroxychloroquine, nintedanib) may be tried