Utilidad diagnóstica de ELISA IgG, IgM, IgA y ELISA avidez de IgG en toxoplasmosis reciente y crónica / Diagnostic utility of ELISA IgG, IgM, IgA and ELISA IgG avidity in recent and chronic toxoplasmosis

ABSTRACT

Toxoplasmosis, a world wide zoonotic infection, is generally asymptomatic and benign in immunocompetent individuals, but it can be serious in immunodeficiencies particulary in patients with acquired immunodeficiency syndrome and in children infected in utero. So, it is important to dispose methods which permit discriminate between recent and chronic infections. In order to contribute to improve the diagnosis of toxoplasmosis ELISA IgG, IgG, IgM, IgA and ELISA IgG, avidity were performed in 15 and 24 sera from patients suspectec of having acute and chronic infection respectively, according dye test (DT) titres. ELISA IgG was positive in both groups, ELISA IgM was positive in 78,6 and 58,3 percent respectively, while ELISA IgA was positive in 85,7 and 33,3 percent of recent and chronic group respectively. In those sera with low IgG avidity (18,8 percent) we found specific IgM in 71,5 and 4,2 percent and IgA in 78,6 and 0,0 percent of recent and chronic groups respectively. Parallelly, 208 sera samples were clasified according to the results of DT, indirect hemagglutination and complement fixation tests in the following groups: acute (97), intermediate (36), chronic (35) and negative (40). The results were: acute (96,9-64,9-55,6 and 65,9 percent); intermediate (97,2-63,8-44,4 and 47,2 percent); chronic (45,7-42,8-5,7 and 34,3 percent) for IgG, IgM, IgA and low IgG avidity respectively. The use of both acute markers, IgA and low IgG avidity in the diagnosis of toxoplasmosis is discussed