Influenza A Infection With Virus-Associated Pneumonia and Hemorrhagic Shock and Encephalopathy Syndrome in an Adult.

Hemorrhagic shock and encephalopathy syndrome (HSES) is a subtype of influenza-associated encephalopathy (IAE) and primarily occurs in infants. It presents with high fever, disorder of consciousness, convulsions, and shock, which rapidly progress to watery diarrhea, as well as liver and renal dysfunction. HSES is extremely rare in adults, with few reported cases worldwide. Here, we report the case of an adult with viral pneumonia and HSES that developed after influenza A infection. Drastic courses, such as those in our case, can follow influenza infections, even in adults, and awareness of HSES development is crucial in cases of suspected influenza virus-induced hypercytokinemia.