Diagnosis of Congenital Toxoplasmosis: No Benefit of IgA Antibody Detection by Platelia ELISA in a Tricentric Evaluation.

The diagnostic accuracy of a commercial Toxoplasma gondii IgA antibody enzyme-linked immunosorbent assay (ELISA) was evaluated in the context of routine practice on 289 newborns with congenital toxoplasmosis (CT) and 220 healthy controls. The performance of this assay was compared to that of the current gold-standard test for anti-Toxoplasma IgM detection, an immunosorbent agglutination assay (ISAGA). IgM and IgA sensitivity and specificity were assessed in cord and postnatal samples. The sensitivity of IgA detection by ELISA on all serum and peripheral blood samples was 60.56% and 56.52%, respectively, which is low compared with the sensitivity of IgM detection by ISAGA (73.26% on serum samples, 82.35% on peripheral blood). Adding the T. gondii IgA antibody ELISA to the diagnostic panel did not significantly increase the overall performance of the serological diagnosis based on IgM detection.

Transient aplastic crisis triggered by parvovirus B19 in a family with hereditary spherocytosis.

Acute parvovirus B19 infection may lead to erythroblastopenia crisis in patients with underlying red blood cells disorders. We report herein an uncommon concomitant transient aplastic crisis in a mother and her daughter, both affected by hereditary spherocytosis. The diagnosis was confirmed by the detection of a very high parvovirus B19 DNA load in both the mother's and daughter's sera, associated with the presence of parvovirus B19 specific immunoglobulin-M antibodies. This rapid etiologic diagnosis allowed to save bone marrow sampling, although blood transfusion was required regarding the severe anemia associated with pancytopenia. Our observation illustrates first line parvovirus B19 hypothesis in the context of transient aplastic crisis and that contagiousness in household contacts should be considered in family with a medical history of red blood cell pathology.