Sepsis Due to Haemophilus influenzae and Masked Influenza A Infection

Haemophilus influenzae (H. influenzae) is a facultative anaerobe, pleomorphic Gram-negative coccobacillus capable of causing various respiratory and blood stream infections. Introduction of childhood immunization against H. influenza type b has decreased its prevalence. Invasive infection with non-typeable H. influenzae is increasing specially in vulnerable population. We present a case of a 69-year-old female who developed septic shock due to H. influenzae infection. She was also found to have influenza A infection in bronchoalveolar lavage (BAL) sample although initial test with nasopharyngeal swab was negative. This case report highlights the fact that in patients with high clinical suspicion, negative nasopharyngeal swab with polymerase chain reaction may not rule out influenza infection and BAL may be necessary to confirm the diagnosis and H. influenzae can be causing bacterial superinfection in such patients. She was appropriately treated with third-generation cephalosporin for H. influenzae and with oseltamivir for influenza A. Her condition improved significantly with the treatment.