Table 2.

Specific serum levels of IgG antibodies to EBNA-2(N) in sera from patients with different connective tissue diseases.¹

		EBNA-2
Diseases of patients groups (no. of specimens)	Median	Mann–Whitney test2
Systemic lupus erythematosus (102)	0·084	P < 0·0001
Primary Sjögrens's syndrome (74)	0·070	P = 0·0005
Rheumatoid arthritis (59)	0·070	P = 0·002
Systemic sclerosis (13)	0·056	n.s.3
Polyomyositis/dermatomyositis (7)	0·042	n.s.
Mixed connective tissue disease (9)	0·070	n.s.
Secondary SS associated with SLE (19)	0·088	P = 0·004
Secondary SS associated RA (23)	0·075	P = 0·002
Secondary SS associated with SSc (9)	0·050	n.s.
Healthy control	0·042

¹Specific serum levels of IgG antibodies to EBNA-2 were calculated by dividing ELISA OD₄₅₀ readings by whole IgG protein concentrations.

²P-values were calculated by comparing the medians of patient groups to that of normal healthy controls.

³Not significant (n.s.).