Evaluation of antibodies in cerebrospinal fluid for the diagnosis of tick-borne encephalitis in dogs

Abstract

Tick-borne encephalitis (TBE) is caused by the neurotropic tick-borne encephalitis virus (TBEV). In dogs, this virus may affect the central nervous system (CNS), causing meningoencephalitis, meningomyelitis, radiculitis or any combination of these. Diagnosis of TBE relies on a combination of clinical signs of CNS disease and laboratory findings, including CSF pleocytosis and serum TBEV antibody titers. Exposure to TBEV does not necessarily cause clinical disease, and seroprevalence has been reported as high as 40% in endemic areas. This causes concerns of over-diagnosing TBE in dogs with CNS disease. By examining TBEV antibodies in dogs with and without neurological disease in a TBEV endemic area, this study aimed to evaluate the diagnostic value of TBEV antibodies in the cerebrospinal fluid (CSF) in dogs. Eighty-nine dogs were included in the study, 56 with neurological disease and 33 neurologically normal control dogs. A positive TBEV CSF and serum IgG antibody titer (> 126 U/mL) was found in 3/89 dogs (3.4%). A positive serum TBEV antibody titer was found in 11 of the 89 dogs (12.4%). None of the control dogs showed a positive CSF antibody titer, whilst two showed positive serum concentrations. A positive CSF IgG antibody titer supports a clinical diagnosis of TBE in patients with acute onset of CNS disease and may help reduce the risk of over-diagnosis.

Comparison of Serological Methods for Tick-Borne Encephalitis Virus-Specific Antibody Detection in Wild Boar and Sheep: Impact of the Screening Approach on the Estimated Seroprevalence

“…Afterwards, the positive samples are subjected to a virus neutralization test, which is considered as the golden standard test for flavivirus antibody detection, to eliminate potential false positive results. From 38 identified screening studies of flavivirus antibodies in animals, 19 used the Immunozym FSME IgG All Species ELISA (Progen, Heidelberg, Germany) [ 12 , 14 , 15 , 19 , 20 , 21 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 ], 10 used the ID Screen WNV Competition ELISA Kit (Innovative diagnostics, Montpellier, France) [ 13 , 33 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 ] and 9 used other ELISA kits [ 9 , 22 , 44 , 45 , 46 , 47 , 48 , 49 , 50 ] as a first screening. Based on this literature study, it was decided to evaluate the performance of the Immunozym ELISA and the IDScreen ELISA in more details.…”

Suspected tick‐borne flavivirus meningoencephalomyelitis in dogs from the UK: six cases (2021)

“…However, a recent study by Salat et al (2021) has also described the presence of seroconversion in experimentally infected dogs without clinical signs, and, therefore, serological results should be analysed in conjunction with the clinical signs. In addition, CSF antibodies would have been a useful test as recently reported by Alnefelt et al (2021). Only one of the deceased dogs underwent post-mortem examination, limiting the diagnosis in the other two dogs.…”

“…This finding is not surprising as the presence of the TBEV in blood and CSF has been reported as insignificant once the initial viremic phase is finished (Kaiser, 1999(Kaiser, , 2012Marriott et al, 2006;Veje et al, 2018). A recent study by Alnefelt et al (2021) has demonstrated the utility of CSF antibody analysis compared to PCR in TBEV and LIV infections. However, in the present study, a dog showed negative TBEV serology and PCR in CSF, but positive immunohistochemistry on post-mortem examination of the brain.…”

“…A recent study by Alnefelt et al . (2021) has demonstrated the utility of CSF antibody analysis compared to PCR in TBEV and LIV infections. However, in the present study, a dog showed negative TBEV serology and PCR in CSF, but positive immunohistochemistry on post‐mortem examination of the brain.…”

“…In addition, CSF antibodies would have been a useful test as recently reported by Alnefelt et al . (2021). Only one of the deceased dogs underwent post‐mortem examination, limiting the diagnosis in the other two dogs.…”