Dados do Trabalho

Título

Evaluation of a multiplex panel for diagnosis of congenital and perinatal infections

Introdução

The development of a multiparametric assay, capable of detecting antibody levels for SToRCH-Z infections, with a minimal amount of blood sample, is necessary.

Objetivo (s)

This work aims to develop a multiparametric assay based on magnetic microspheres, capable of detecting antibody levels (IgG and IgM) against congenital and perinatal infections, such as syphilis, HIV, and toxoplasmosis, among others, with a minimal amount of blood sample.

Material e Métodos

A total of 112 sera samples from pregnant women and international panels for eight SToRCH-Z were analyzed after optimization of the multiparametric assay. Evaluation of the antigen’s concentration used in the coupling to the magnectic beads was performed separately for each SToRCH-Z infection. According by the manufacturer’s instructions, the buffer (MES, PBS and NaHCO3) and conjugate (1:1000) and samples dilutions (1:200) were determinate from the highest ratio (HCV antigen=107) between the results of the positive and negative controls. Due to the prevalence of approximately 99% of CMV in Brazil, varying from 80 to 99% in the world, it was necessary to perform IgM research for CMV. We selected 23 samples, 15 from pregnant women and 8 from the international panel for CMV and IgM research was performed, being considered positive the samples that presented MFI higher than 200 according to the determined cutoff.

Resultados e Conclusão

The standardization of the test for the detection of antibodies for eight of the microorganisms responsible for SToRCH-Z infections combined, was carried out with satisfactory preliminary results, without interference between the antigens, presenting similar results to the conventional single tests (Rubella p=0,0057, CMV p=0,4857, Syphilis p=0,6857, HBc p=0,8857, Zikavirus p=0,8955, Toxoplasmosis p=0,8411, HCV p=0,926 and HIV p=0,6677) .The preliminary results obtained by multiparametric assay were compared with standard methodology and were satisfactory (95%) for the detection of IgG antibodies against the analyzed diseases.The specific IgM antibodies were found to be positive in 15 sera samples (65%) for CMV indicating a recent infection. Multiparametric assay based on magnetic microspheres could be used routinely screened for the SToRCH-Z infections, and permit for carrying out early interventions to prevent fetal loss in maternal and child reference units.

Palavras-chave

SToRCH-Z infections, prenatal treatment, multiparametric assay

Agradecimentos

FIOCRUZ (BIO-MANGUINHOS e IFF)