Detection of Tick-Borne Encephalitis Virus RNA in Urine

Abstract

b T ick-borne encephalitis (TBE) is a viral zoonosis of increasing incidence in Eurasia, and diagnosis relies mainly on the detection of IgM antibodies in serum. We here present two cases of TBE, of four patients tested, in which we have detected TBE virus (TBEV) RNA in urine with real-time PCR during the encephalitic phase. This observation suggests a new diagnostic opportunity that could be evaluated in a larger cohort of patients.In the first case we report here, 1 week after a tick bite, a 61-yearold woman had high fever, nausea, and fatigue lasting for 5 to 6 days. She was asymptomatic for a week, after which the fever returned along with vomiting and severe headache. After admission, her condition worsened. She was unable to follow instructions, became somnolent and disoriented, and had signs of dysphasia. A cerebrospinal fluid (CSF) sample showed a leukocyte count of 69 ϫ 10 6 /liter (41% polymorphonuclear and 59% mononuclear) and elevated albumin. Specific TBE virus (TBEV) IgM antibodies were detected in serum drawn on day 2 after admission, and the patient seroconverted as regards IgG during the hospital stay. Before nucleic acid extraction using the EasyMag instrument (bioMérieux, Marcy l=Etoile, France), 250-l amounts of serum, CSF, and urine samples were added to 2 ml of lysis buffer and incubated for 10 min at room temperature. TBEV RNA was detected from urine by TaqMan PCR performed as described previously (1) on day 19 after fever onset (Fig. 1). The patient's condition improved, and she was discharged after 10 days of hospitalization.The second case was a 70-year-old woman who reported several tick bites during the preceding weeks and was admitted 2 days after the onset of high fever, nausea, and fatigue. She was on treatment with immunosuppressive drugs (mycophenolate, tacrolimus, and prednisolone) due to kidney transplantation. She developed paresis of the lower extremities and lost the strength in her hands. A CSF sample showed 488 ϫ 10 6 leukocytes/liter (28% polymorphonuclear and 72% mononuclear), elevated albumin and lactate, and a slightly decreased glucose quotient. TBEV IgM antibodies (but not IgG) were detected in serum. On day 8 after admission, the patient became deeply unconscious, had a generalized status epilepticus, and was intubated. Magnetic resonance imaging (MRI) demonstrated high signals in the amygdala and hippocampus. Her neurological condition deteriorated, and she died 11 weeks after admission. TBEV RNA was detected from urine on day 7 and day 16 after onset ( Fig. 1). The RNA quantities allowed sequencing of 10,432 nt from TBEV RNA amplicons, as

Powassan Virus Neuropathology and Genomic Diversity in Patients With Fatal Encephalitis

“…The absence of POWV RNA from the blood of Subject A (1 week after symptom onset) is compatible with the hypothesis that POWV confers a short period of viremia, similar to other neuroinvasive flaviviruses [ 29–31 ]. The absence of POWV RNA in the urine of Subject A and the kidney of Subject B is notable because other flaviviruses including Zika virus and tick-borne encephalitis virus are often detectable in urine [ 32 , 33 ].…”

EAN consensus review on prevention, diagnosis and management of tick‐borne encephalitis

“…In fatal encephalitic cases, TBEV can be detected in the brain tissue by PCR [65,114,[145][146][147][148]. In a few cases, TBEV RNA was detected in urine by PCR in the encephalitic phase of TBE [149]. However, the value of this diagnostic approach needs further evaluation.…”

Contact-Dependent Transmission of Langat and Tick-Borne Encephalitis Virus in Type I Interferon Receptor 1-Deficient Mice

“…Other natural transmission routes, such as inhalation of aerosolized rodent excretions in the case of hantavirus infections (22) or sexual transmission between humans as for ZIKV (23,24), have not been described for TBEV so far. Excretions and the persistence of contagious body fluids in infected humans are documented only in immunocompromised patients for TBEV (25,26). The risk of contact exposure to infectious body fluids remains unclear.…”