PERSISTENCE OF PLACENTALLY TRANSMITTED TOXOPLASMIC ANTIBODIES IN NORMAL CHILDREN IN RELATION TO DIAGNOSIS OF CONGENITAL TOXOPLASMOSIS

[摘要] Quantitative tests for neutralizing (dye test) and complement-fixing (C-F) toxoplasmic antibodies on the sera of three mothers, each of whom had given birth first to a child with congenital toxoplasmosis and then to a normal child, as well as on the sera of these children indicated that:A. Both types of antibody are transmitted to the normal child almost quantitatively and persist in almost undiminished concentration for the first six weeks of life.B. By the end of three months a 4- to 8-fold decrease in titer was found, which progressed to a 32-fold diminution at the end of 4½ months.C. The neutralizing antibody, being detectable in higher dilutions of serum than the C-F antibody, is demonstrable in diminishing amounts for a longer period and was still present in minute amounts at nine months after birth.Tests on seven children, aged 4 to 12 months, who had congenital neurologic disturbances of unknown etiology and whose mothers all had toxoplasmic antibodies in varying titers provided additional evidence that the antibodies, which may occur among certain women of childbearing age without reference to active toxoplasmic infection, did not persist in their children after the fourth month of life. Similar tests on four children, aged 5 weeks to 9 months, in whom the diagnosis of congenital toxoplasmosis could be confirmed by the quantative serologic methods, indicated that in infected children the antibodies did not first disappear and then reappear, but rather persisted in undiminished or higher concentration. The absence of C-F antibody during the first six weeks of life from the serum of a child who has a high titer of neutralizing antibody and whose mother has high titers of both C-F and neutralizing antibody should suggest active infection with Toxoplasma.

[学科分类] 儿科学