Secondary Organizing Pneumonia complicating influenza B

Influenza A and B viruses cause acute viral respiratory illness and can cause various respiratory complications including influenza pneumonia and coinfection with other bacteria. Secondary Organizing Pneumonia (SOP) has rarely been reported as a complication of influenza pneumonia. Most of these cases are secondary to influenza A. SOP due to influenza B is seldom reported. We report a patient with influenza B pneumonia with persistent clinical and radiological worsening despite antivirals and antibiotics. A differential diagnosis of either secondary infection or SOP was considered. The patient underwent fibreoptic bronchoscopy and bronchoalveolar lavage which ruled out infection. The patient was managed as SOP with steroids and had a good response to treatment. The use of steroids in influenza has been shown to worsen mortality. However, in our patient, once infection was ruled out, steroids proved to be lifesaving.