Successful management of refractory respiratory failure caused by avian influenza H7N9 and secondary organizing pneumonia: a case report and literature review

BACKGROUD: Organizing pneumonia (OP) is a rare complication of influenza infection that has substantial morbidity. We report the first case of OP associated with avian influenza H7N9 infection that had significant improvement with corticosteroid treatment. CASE PRESENTATION: A 35-year-old male admitted to intensive care unit because of respiratory failure. He was diagnosed as severe pneumonia caused by avian influenza H7N9 viral infection. After initial clinical improvement supported by extracorporeal membrane oxygenation (ECMO), the patient’s condition worsened with persistent fever, refractory hypoxemia. Chest x-rays and computed tomographies showed areas of consolidation and ground glass opacification. Although OP was suspected and 1 mg/kg methylprednisolone was used, the patient’s condition didn’t improved considerably. An open lung biopsy was performed, and histopathological examination of the specimen was compatible with OP. The patient was treated with methylprednisolone 1.5 mg/kg for 5 days. ECMO was weaned on day 15, and he was discharged on day 71 with good lung recovery. CONCLUSIONS: To the best of our knowledge, this was the first case of successful management of refractory severe respiratory failure caused by avian influenza H7N9 infection complicated with OP. Refractory hypoxia with clinical manifestation and radiological findings compatible with OP, a differential diagnosis should be considered among patients at the second or third week of influenza H7N9 infection, especially in patients with clinical condition deteriorated after the primary influenza pneumonia was controlled. And a steroid dose of methylprednisolone 1.5 mg/kg may be suggested for treatment of OP associated with avian influenza H7N9 infection.