How a mild influenza B infection can kill: A case of pulmonary hemorrhage

Viral influenza is a seasonal infection associated with significant morbidity and mortality. Rapidly fatal hemorrhagic pneumonia has been described in previously healthy individuals with β-hemolytic Streptococcus pneumoniae in a small series of patients, but it is not common in patients coinfected with influenza B and β-hemolytic Streptococcus, particularly since influenza B is considered less pathogenic than influenza A. However, despite being uncommon, this coinfection seems to be associated with high morbidity and mortality, particularly in healthy individuals. We present a case of a 46-year-old previously healthy white woman presenting with 4 days of shortness of breath, sore throat, subjective fevers, and nonproductive cough with rapidly fatal hemorrhagic pneumonia confirmed to have Group A β-hemolytic Streptococcus and influenza B coinfection. On admission, she had a temperature of 103° F, room air oxygen saturation of 95%, a positive nasal swab for influenza B, and negative rapid strep test. Initial chest radiograph showed increased bibasilar interstitial markings. She was admitted to a regular floor and started on oseltamivir. Preliminary throat culture was positive for Group A β-hemolytic Streptococcus and penicillin V was started. Respiratory status deteriorated requiring intubation and transfer to Intensive Care Unit. Subsequently, copious bleeding was noted in her endotracheal tube. A bedside bronchoscopy with bronchoalveolar lavage revealed a hemorrhagic pneumonitis. Despite aggressive efforts, she developed shock, arrested, and died Western District Office of the Chief Medical Examiner, Roanoke, VA, USA postadmission. Blood cultures, bronchoalveolar lavage, and postmortem pulmonary tissue grew Group A β-hemolytic Streptococcus, only resistant to erythromycin.