Introduction Obliterative bronchiolitis (OB) is a rare form of chronic obstructive lung disease that follows a severe insult to the lower respiratory tract, resulting in fibrosis of the small airways. In the non-transplant paediatric population, adenovirus infection is the most common cause. The initial infective insult occurs in the early years and the diagnosis requires a history of acute severe bronchiolitis/viral pneumonia in previously healthy children in the first 3 years of life. Though there has been a case report of post-infectious OB in an adult female,¹ to our knowledge, there are no published cases in children acquired after 3 years of age.

Aim We describe two previously healthy older boys with normal immunological investigations who developed post-infectious OB.

Cases The first patient had severe adenovirus pneumonia aged 7, requiring ventilation, oxygen and bronchodilator therapy. In view of atopic background (nut allergy and paternal asthma) inhaled corticosteroids were initiated at discharge. A year later he presented with productive cough, debilitating shortness of breath on exertion, moderately reduced PEFR but no wheeze. He did not respond to Amoxicillin or step-up asthma treatments. CXR and exercise test were normal and pulmonary function tests (PFT) did not show evidence of reversibility. A mixed growth of typical respiratory pathogens were isolated in sputum and treated with prolonged oral antibiotic course. High resolution chest CT (HRCT) showed air trapping in the right upper lobe consistent with OB.

The second patient developed severe mixed mycoplasma and adenovirus pneumonia aged 3.5, followed by persistent left lower lobe collapse and wet cough requiring intravenous antibiotics and physiotherapy. His left lower lobe re-expanded, but his HRCT revealed air trapping consistent with OB. He continued to have intermittent chest infections with various typical respiratory pathogens isolated in sputum requiring oral and intravenous antibiotics. His PFTs are stable with moderately reduced FEV1/FVC.

Both patients are maintained on regular chest physiotherapy and intermittent antibiotics.

Conclusion Post-infectious OB can develop in healthy children older than 3 years.

Reference 1 Marinopoulos GC, Huddle KR, Wainwright H. Obliterative bronchiolitis: virus induced? Chest 1991;99(1):243–5