A case of fatal haemorrhagic fever associated with tick-borne encephalitis virus infection.

Abstract

Tick-borne encephalitis virus (TBEV) is a vector-borne orthoflavivirus responsible for monophasic or biphasic disease with central nervous system manifestations. A middle-aged, severely immunocompromised woman became gradually more febrile after a forest hike. She was admitted to hospital with thrombocytopenia, leukopenia and elevated liver enzymes as well as ecchymosis on the truncus. During her hospitalization, she experienced repeated severe haemorrhages from different retroperitoneal blood vessels. Despite successful embolization of the bleeding vessels, she died in circulatory shock due to compression of the inferior vena cava from large retroperitoneal hematomas. Autopsy did not reveal any sign of encephalitis. TBEV was detected in blood plasma and cerebrospinal fluid by PCR. Whole genome sequencing demonstrated clustering with the Kumlinge A52 isolates from Finland, a variant of European TBE.