Evaluation of a new kit of the 3rd generation, EIA Borrelia recombinant IgM in the serodiagnosis of
Lyme borreliosis (LB) and comparison with the EIA test based on the whole cell antigen in the detection of IgM antibodies.
MATERIAL AND METHODS:
In total 123 children (147 sera) were examined, 71 children (93 sera) of whom showed clinically defined stage of LB. The other 54 sera of 52 children were tested for suspicion for LB which was later excluded, and for cross-reacting antibodies. They represented the control group of children with other infectious or autoimmune diseases. The EIA B. recombinant IgM kit (Test-Line, CR) is based on the selected antigen fragments: outer surface protein C (OspC) and internal flagellin (p41i). The fragments were selected according to the most frequent Borrelia spp. in the Czech Republic.
Samples compared 101/147 (69 %) with both tests showed correspondent reactions. 46 samples reacted inconsistently, 26 from children with LB and 20 from the control group. The total specificity and sensitivity of the recombinant kit in IgM antibody class was 88,9 % and 26,9 %, respectively. In the case of early disseminated LB infection the sensitivity was 35,6 % and it is comparable with the sensitivity of immunoblot. Statistically, there is no difference in the sensitivity (p = 0,101) and specificity (p = 0,383) of EIA B. recombinant IgM and immunoblot.
The EIA B. recombinant IgM kit shows comparable diagnostic sensitivity in children with acute LB together with significantly higher specificity in children with non-specific response in kits based on the whole cell antigen and at the same time high conformity with results of IgM class immunoblot. This kit of the 3rd generation is reliable for screening of IgM antibodies.