Plastic bronchitis associated with adenovirus infection

Abstract

A previously healthy 3-year-old boy who presented with an 8-day history of persistent fever and cough was referred to our hospital. On physical examination the boy had signs of respiratory distress and a low-pitched breath sound on his left lung. He had no history of foreign-body aspiration. A chest radiograph done 2 days previously was normal. On the day of admission he had a CT scan of his chest, which revealed left lower lobe atelectasis (appendix). Results of direct immunofluorescence of nasopharyngeal swabs for the detection of respiratory syncytial virus, influenza A and B viruses, parainfluenza viruses, and adenovirus were negative. RT-PCR for Mycoplasma pneumoniae in nasopharyngeal swabs was also negative. Flexible bronchscopy and bronchoalveolar lavage showed the complete obstruction of the left lower bronchus by a whitish rubbery material. A bronchial tree-like cast was extracted via suctioning during flexible bronchoscopy (figure); it was composed of fibrinous material containing neutrophils and eosinophils on haematoxylin and eosin stain (appendix). Bronchoalveolar lavage fluid was analysed for the presence of virus by direct immunofluorescence assay and was positive for adenovirus. Next-generation sequencing for pathogens in the bronchoalveolar lavage fluid was also positive for adenovirus B1. 1 day after bronchoscopy, the boy's temperature was normal, and on the third day chest radiograph showed complete resolution (appendix).