IgG Avidity: an Important Serologic Marker for the Diagnosis of Tick-Borne Encephalitis Virus Infection.
A total of 52 serum samples from patients with symptoms suggestive of tick-borne encephalitis virus (TBEV) infection and positive IgM and/or IgG antibodies were tested for IgG avidity. Acute/recent TBEV infection was confirmed by low/borderline avidity index (AI) in 94.8% IgM positive/IgG positive samples, while in 5.2% high AI was found indicating persisting IgM antibodies. Majority of IgM negative/IgG positive samples (78.6%) showed high AI consistent with past TBEV infection. However, in 21.3% patients without measurable IgM antibodies current/recent infection was confirmed by AI. IgG avidity represents an additional serologic marker that improves diagnosis of TBEV, especially in cases of atypical antibody response.
Tatjana
T
Vilibic-Cavlek
Ljubo
L
Barbic
Vladimir
V
Stevanovic
Goranka
G
Petrovic
Gordana
G
Mlinaric-Galinovic
D000914:Antibodies, Viral / Q000097:blood*; D000915:Antibody Affinity / Q000502:physiology*; D015415:Biomarkers; D004669:Encephalitis Viruses, Tick-Borne / Q000276:immunology*; D004675:Encephalitis, Tick-Borne / Q000097:blood* / Q000175:diagnosis* / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D007075:Immunoglobulin M / Q000097:blood
D000914:Antibodies, Viral; D015415:Biomarkers; D007074:Immunoglobulin G; D007075:Immunoglobulin M