Diagnosis of toxoplasmosis by joint detection of immunoglobulin A and immunoglobulin M.
An indirect immunofluorescence test with total anti-human immunoglobulin conjugate (IgG,A,M-IIF) can be used for joint detection of immunoglobulin A (IgA) and IgM antibodies, provided serum IgG is previously absorbed with anti-human IgG. To determine the validity of the IgG,A,M-IIF assay with absorbed sera, the results obtained were compared with those obtained by methods routinely used for the detection of acute-phase markers, IgA and IgM IIF and enzyme immunoassay. Accordingly, 114 serum samples were selected from patients showing titers of > or = 1:1,024 by IgG,A,M-IIF. (i) In 90 of the samples, neither IgA nor IgM was detected by any of the methods employed; (ii) the remaining 24 samples showed IgA and/or IgM. In all cases, the IgG,A,M-IIF assay with absorbed sera was positive. These comparative data support the use of IgG,A,M-IIF, performed with absorbed and unabsorbed sera simultaneously, for determining the presence of specific IgG, IgA, and IgM by employing a single technique (IIF), one conjugate (anti-IgG,A,M), and only one sample (with and without previous absorption), thus providing a useful initial tool for the diagnosis of toxoplasmosis.
Arcavi
M
M
Immunología Clínica, Departamento de Bioquímica Clinica, Facultad de Farmacia y Bioquímica, Hospital de Clínicas Jose de San Martín, Universidad de Buenos Aires, Argentina.
Orfus
G
G
Griemberg
G
G
D000465:Algorithms; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood*; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect / Q000379:methods*; D006801:Humans; D007106:Immune Sera; D007070:Immunoglobulin A / Q000097:blood*; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood*; D008297:Male; D011247:Pregnancy; D014122:Toxoplasma / Q000276:immunology*; D014123:Toxoplasmosis / Q000175:diagnosis*
D000913:Antibodies, Protozoan; D007106:Immune Sera; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M