One Plastic Bronchitis Patient With Influenza A (H3N2) And Human Bocavirus Infection: Case Report And Literature Review

Objective：Plastic bronchitis is one of severe cases of paediatrics，whose clinical characteristic is extensive bronchial blockage caused byendogenous airway foreign body，leading to dysfunction of venting and airexchange of the lung， which may end up with death of respiratory failurecaused by hypoxia if not treated in time. The endogenous foreign body inthe airway caused by the disease is jelly-like that will fill and block alongthe bronchial widely when it gets severe，forming the shape of the bronchialtree while being removed，so it is called plastic bronchitis. The etiology isstill unclear. By referring to the first identified case of plastic bronchitis inour hospital and reviewing related documents，its clinical features andetiological diagnosis of virus have been summarized.Methods：A child of more than5years old was enrolled. Clinicalmanifestations were fever， cough， gasp， anhelation and progressivedifficulty of breath. Thoracic CT showed that the left lung had large parts ofconsolidation，possibly being pulmonary atelectasis. Bronchoscopy andlavage were conducted and the ingrown foreign body in the air passage was taken out. The diagnosis was plastic bronchitis. Bronchoalveolar lavagefluid of the sick child was taken out for detecting16kinds of respiratoryviruses.Results：Detecting results of16kinds of respiratory viruses indicatedthat the sick child was influenza A virus positive，and the NP sequencing ofthe further amplified virus was clarified as H3N2. At the same time，humanbocavirus（HBoV）were found out and the number of virus copy was3×105copies/ml. The child was discharged from the hospital after the endogenousforeign matter was taken out.Conclusions：As one of kind of pediatric intensive cases，plasticbronchitis can be clearly diagnosed by bronchoscopy and lavage removingendogenous foreign body，which is essential for the effective treatment. Thepatient’s bronchoalveolar lavage etiological diagnosis remind us of mixedinfection of human influenza viruses and HBoV， which is worthy ofattention.