title: First cases of human Usutu virus neuroinvasive infection in Croatia, August-September 2013: clinical and laboratory features.
abstract: Few reports of human Usutu virus (USUV) infection have been reported to date. We describe the first three patients with USUV neuroinvasive infection in Zagreb and its surroundings from 30 August to 7 September 2013 during a West Nile virus (WNV) outbreak. Patients were aged 29, 56, and 61 years. The two older patients had several comorbidities (arterial hypertension, hyperlipidemia, and diabetes mellitus). All patients presented with meningitis and meningoencephalitis closely resembling WNV neuroinvasive disease. The main clinical features in all patients were headache, fever, nuchal rigidity, hand tremor, and hyperreflexia. Neuroimaging studies were normal and electroencephalography (EEG) revealed diffusely slow activity. The 29 years old, a previously healthy female patient, was deeply somnolent and disoriented for 4 days. Her recovery was slow and even 10 weeks after disease onset, she had memory and speech-fluency difficulties. The other two patients recovered promptly. USUV IgG antibodies were detected in all patients by ELISA with seroconversion documented in two of them. Titers of USUV-neutralizing antibodies were 10, 80, and 10, respectively. Because USUV and WNV share many clinical characteristics, USUV infection could be misdiagnosed as WNV. Testing for USUV should be considered in all suspected cases of meningoencephalitis, especially in areas where both viruses cocirculate.
authors.affiliation: Department for Intensive Care Medicine and Neuroinfectology, University Hospital for Infectious Diseases "Dr Fran Mihaljevic", Mirogojska 8, 10000, Zagreb, Croatia, marija.santini@zg.t-com.hr.
authors.forename: Marija
authors.initials: M
authors.lastname: Santini
authors.forename: Tatjana
authors.initials: T
authors.lastname: Vilibic-Cavlek
authors.forename: Bruno
authors.initials: B
authors.lastname: Barsic
authors.forename: Ljubo
authors.initials: L
authors.lastname: Barbic
authors.forename: Vladimir
authors.initials: V
authors.lastname: Savic
authors.forename: Vladimir
authors.initials: V
authors.lastname: Stevanovic
authors.forename: Eddy
authors.initials: E
authors.lastname: Listes
authors.forename: Annapia
authors.initials: A
authors.lastname: Di Gennaro
authors.forename: Giovanni
authors.initials: G
authors.lastname: Savini
mesh_terms: D000328:Adult; D057134:Antibodies, Neutralizing / Q000097:blood; D000914:Antibodies, Viral / Q000097:blood*; D017523:Croatia / Q000453:epidemiology; D003937:Diagnosis, Differential; D004196:Disease Outbreaks; D018349:Encephalitis Viruses, Japanese / Q000302:isolation & purification* / Q000472:pathogenicity; D004671:Encephalitis, Arbovirus / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology / Q000821:virology; D005260:Female; D018177:Flavivirus Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology / Q000821:virology; D006801:Humans; D008297:Male; D008590:Meningoencephalitis / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology / Q000821:virology; D008875:Middle Aged; D014901:West Nile Fever / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology / Q000821:virology; D014902:West Nile virus / Q000472:pathogenicity
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral