Abstract
An 8-month-old girl with respiratory distressand stridor was admitted to our hospital. Two days later, she died of respiratory insufficiency due to pneumonia. Autopsy confirmed the presence of follicular bronchiolitis (FBB) in both lungs. After consideration of her clinical course, we focused on three pathogens: Legionella pneumophilia , Pneumocystis carinii , and Mycobacterium tuberculosis . Only Legionella pneumophilia was detected by both immunohistochemistry and polymerase chain reaction.