Evaluation of the TGS TA system for the detection of anti-cytomegalovirus antibodies

Background and aims: The aim of the present study was to evaluate the new Technogenetics TGS TA system for detecting anti-Cytomegalovirus IgG and IgM antibodies and IgG avidity. The TGS TA system was compared with our routinely used system, LIAISON XL, for the detection of IgG and IgM antibodies. Only in positive IgM samples, TGS TA system was compared to an enzyme linked fluorescent assay (ELFA) test (VIDAS, BioMérieux, Marcy-l’Étoile, France) and with LIAISON XL system for the IgG avidity (if possible).
Materials and methods: Three hundred sera samples from pregnant women were examined with the TGS TA system and divided in 3 groups according to IgG and IgM screening LIAISON XL tests: 102 were non-immune women (Group 1), 98 were pregnant with past infection (Group 2) and 100 were pregnant with positive or equivocal IgM (95 with positive IgG and 5 with negative IgG) (Group 3).
Results: The overall concordance of the IgG results between LIAISON XL and TGS TA was 98.3%: 97.1% in Group 1, 100% in Group 2 and 98.0% in Group 3. The overall concordance of the IgM results between LIAISON XL and TGS TA was 92.1%: 100% in Group 1, 99.0% in Group 2 and 70.1% in Group 3. In Group 3, the concordance between the results of the IgG avidity with the LIAISON XL and TGS TA tests was 87.4%. Comparing the clinical diagnosis obtained with our protocol and that of the TGS TA system, the overall concordance was 94.3%: 97.1% in Group 1, 99.0% in Group 2 and 87.0% in Group 3.
Conclusions: In conclusion, the overall clinical concordance between the LIAISON XL/VIDAS protocol and the TGS TA system is excellent. TGA TA system shows to be a valuable tool able to clearly identify non-specific subjects, those with a non-recent infection and classify as either recent or past infection half of the subjects with undetermined infection with our protocol.