Reliability of the Siemens Enzygnost and Novagnost Epstein–Barr Virus assays for routine laboratory diagnosis: agreement with clinical diagnosis and comparison with the Merifluor Epstein–Barr Virus immunofluorescence assay

Table 6 Results using the Novagnost assays, including indeterminates, as compared to established EBV status

		Novagnost interpretation
		Determined			Indeterminate
		Negative	Acute infection	Past infection	Isolated EBNA-1 (probable past infection)	Isolated VCA IgG (EBNA-1 lost, probable past infection)	All positive (probable past infection)	% agreement with EBV status
	Negative^a (N = 39)	35	1	1	0	0	0	89.7
	Acute infection (N = 15)	0	15	0	0	0	0	100%
	Past infection (N = 464)	5	0	399	8	55	2	86^b
EBV status								98.8^c
								87.7^d
								97.8^e
								99.6^f

^a Determination could not be made for 2 sera which did not match any of the indeterminate types listed in the table.
^b Agreement if all indeterminate results are included in the analysis.
^c Agreement if all indeterminate results are excluded from the analysis (i.e., 399/404).
^d Agreement if all isolated EBNA-1 results are assumed to represent past infections.
^e Agreement if results are considered indeterminate because they are VCA IgG⁺–only (isolated VCA IgG) are instead considered positive, and thus also most likely represent past infections.
^f Agreement if all isolated EBNA-1 and all isolated VCA IgG⁺ results are assumed to represent past infections.

ISSN: 1471-2334