Utility of Borrelia burgdorferi sensu stricto C6 Peptide for Serologic Confirmation of Erythema-Free Ixodid Tick-Borne Borrelioses in Russia

Table 4

Frequency of positive antibody responses to Borrelia antigens in serum samples (N = 1018) from ITBB patients.

Patient Group	No. of sera	Number (%) of positive sera (at the baseline and convalescent) to Borrelia antigens
		OspC IgM	VlsE IgM	C6 IgM	C6 IgG	C6 IgM/IgG	C6 IgM/IgG + VlsE IgM
EM patients	498	78 (15.7)	65 (13.1)	87 (17.5)	241 (48.4)	266 (53.4)	267 (53.6)
EM/HGA patients	215	95 (44.2)	117 (54.4)	101 (47.0)	172 (80.0)	177 (82.3)	182 (84.7)
EM/TBE patients	43	4 (9.3)	6 (14.0)	9 (20.9)	13 (30.2)	17 (39.5)	20 (46.5)
EMF patients	81	7 (8.6)	26 (32.1)	28 (34.6)	23 (28.4)	45 (55.6)	51 (63.0)
EMF/HGA patients	106	24 (22.6)	44 (41.5)	36 (34.0)	30 (28.3)	48 (45.3)	66 (62.3)
EMF/TBE patients	75	15 (20.0)	20 (26.7)	27 (36.0)	37 (49.3)	50 (66.7)	59 (78.7)

EM = erythema migrans, EMF = erythema migrans-free, EM/HGA = EM patients coinfected with HGA agent, EM/TBE = EM patients coinfected with TBE virus, EMF/HGA = EMF patients coinfected with HGA agent, and EMF/TBE = EMF patients coinfected with TBE virus. Statistically significant differences (Fisher’s exact test, p < 0.05) were observed for comparison of pairs: C6 IgG versus OspC IgM, VlsE IgM, and C6 IgM in EM patients; C6 IgG versus OspC IgM, VlsE IgM, and C6 IgM in EM/HGA patients; C6 IgG versus OspC IgM in EMF patients; C6 IgG versus OspC IgM and VlsE IgM in EMF/TBE patients; C6 IgM/IgG versus C6 IgG in EMF/HGA patients; C6 IgM/IgG versus C6 IgG in EMF/TBE patients; C6 IgM/IgG+VlsE IgM versus C6 IgM/IgG in EMF/HGA patients; C6 IgG in EM/HGA patients versus C6 IgG in other groups of patients; C6 IgM in EM/HGA patients versus C6 IgM in EM patients and EM/TBE patients; C6 IgM/IgG in EM/HGA patients versus C6 IgM/IgG in other groups of patients. All other comparisons were not statistically significant.