Specific anti-toxoplasmic IgG antibody immunoblot profiles in patients with AIDS-associated Toxoplasma encephalitis

Among 186 suspected cases of Toxoplasma encephalitis (TE) ill HIV-infected patients, 113 were classified as TE and 73 as non-TE. Serum Toxoplasma gond ii (T.g.) antibodies were detected by ELISA in 97% of TE vs 71% of non-TE c ases (p < 0.001). In the 164 patients positive for T. g. antibodies, the Ig G 27 and 32 bands were more frequently present in TE than in non-TE (p = 0. 003, p = 0.002, respectively). Among patients with positive T.g. serology, multivariate analysis showed that the presence of an IgG32 (OR 3.1) or IgG2 7 band (OR 2.7) on Western blot mas highly indicative of TE independently o f each other. Positive T.g, serology, but not anti T.g IgG antibody titres, tons predictive. Thus, the positivity of IgG 27 and 32 bands on Western bl ot analysis provides useful data for improving the diagnosis of presumptive TE in HIV-infected patients with suspected TE and positive Toxoplasma sero logy. (C) 1999 Elsevier Science Inc.