Eurico Camargo Neto

Newborn Screening for Congenital Infectious Diseases

To estimate the prevalence of congenital toxoplasmosis, Chagas disease, cytomegalovirus, and rubella, blood samples on dried blood spot (DBS) from neonates (day 3–20 of life) were screened for immunoglobulin (Ig) M against Toxoplasma gondii, cytomegalovirus, rubella virus, and IgG against Trypanosoma cruzi by methods used for serum and adapted for use with DBS. Positive samples were further analyzed for IgM and IgG in serum from neonates and mothers. DBS samples from 364,130 neonates were tested for Toxoplasma gondii–specific IgM, and 15,873 neonates were also tested for IgM against cytomegalovirus and rubella virus and for Trypanosoma cruzi–specific IgG. A total of 195 were diagnosed with congenital toxoplasmosis, 16 with cytomegalovirus, and 11 with congenital rubella. One newborn had a confirmed result for Chagas disease, and 21 mothers had positive serum antibodies. These results suggest that infectious diseases should be considered for future inclusion in programs for newborn screening of metabolic diseases in disease-endemic areas.

Neonatal screening for hemoglobinopathies: a pilot study in Porto Alegre, Rio Grande do Sul, Brazil

Following a previous evaluation of concept, item and semantic equivalences, this paper assesses the measurement equivalence between a Portuguese version of Revised Conflict Tactics Scales (CTS2) and the original instrument conceived in English. The CTS2 has been widely used to tap violence between couples. An intra-observer reliability evaluation involved 165 replications carried out within a 24-48 hour period. Kappa point-estimates were above 0.75 for all scales except sexual coercion. The analysis of internal consistency concerned 768 subjects with complete sets of items. Kuder-Richardson-20 estimates ranged from 0.65 to 0.86. Results were similar to those found in the original instrument in English for the negotiation, psychological aggression and physical violence scales, yet not so for the sexual coercion and injury scales. Factor analysis identified factors with a recognizable correspondence to the underlying dimensions, although a few inconsistencies were detected. For the assessment of construct validity (n = 528) associations between the instruments scales were evaluated, as well as the relationships between violence and putative underlying dimensions. Overall, the findings suggest that the version can be used in the Brazilian context, although further investigation should be carried out to unveil some important remaining issues.This study was conducted to establish the frequency of hemoglobinopathies among newborns undergoing screening tests for metabolic diseases at the University Hospital (Hospital de Clínicas) in Porto Alegre, Rio Grande do Sul, Brazil. Testing for abnormal hemoglobins was performed by isoelectric focusing electrophoresis on agarose gel with blood obtained by heel stick and applied to filter paper. For confirmatory testing of abnormal neonatal screening, a venopuncture blood sample was obtained from the infant and parents and then submitted to hemoglobin electrophoresis on cellulose acetate at pH 8.6 and citrate agar at pH 6.2. A total of 1,615 subjects were studied: 20 samples showed the Hb S pattern and six samples showed Hb C. Thus, frequency of the sickle cell gene was 1.2% and that of the Hb C gene was 0.4%, regardless of race or origin. These data suggest that the inclusion of universal neonatal screening for hemoglobinopathies in the ongoing projects for the detection of phenylketonuria and congenital hypothyroidism has many advantages and should be considered in health programs.

Triagem neonatal para hemoglobinopatias: um estudo piloto em Porto Alegre, Rio Grande do Sul, Brasil

This study was conducted to establish the frequency of hemoglobinopathies among newborns undergoing screening tests for metabolic diseases at the University Hospital (Hospital de Clinicas) in Porto Alegre, Rio Grande do Sul, Brazil. Testing for abnormal hemoglobins was performed by isoelectric focusing electrophoresis on agarose gel with blood obtained by heel stick and applied to filter paper. For confirmatory testing of abnormal neonatal screening, a venopuncture blood sample was obtained from the infant and parents and then submitted to hemoglobin electrophoresis on cellulose acetate at pH 8.6 and citrate agar at pH 6.2. A total of 1,615 subjects were studied: 20 samples showed the Hb S pattern and six samples showed Hb C. Thus, frequency of the sickle cell gene was 1.2% and that of the Hb C gene was 0.4%, regardless of race or origin. These data suggest that the inclusion of universal neonatal screening for hemoglobinopathies in the ongoing projects for the detection of phenylketonuria and congenital hypothyroidism has many advantages and should be considered in health programs.

Investigation of newborns with abnormal results in a newborn screening program for four lysosomal storage diseases in Brazil

Lysosomal storage diseases (LSDs) are genetic disorders, clinically heterogeneous, mainly caused by defects in genes encoding lysosomal enzymes that degrade macromolecules. Several LSDs already have specific therapies that may improve clinical outcomes, especially if introduced early in life. With this aim, screening methods have been established and newborn screening (NBS) for some LSDs has been developed. Such programs should include additional procedures for the confirmation (or not) of the cases that had an abnormal result in the initial screening. We present here the methods and results of the additional investigation performed in four babies with positive initial screening results in a program of NBS for LSDs performed by a private laboratory in over 10,000 newborns in Brazil. The suspicion in these cases was of Mucopolysaccharidosis I - MPS I (in two babies), Pompe disease and Gaucher disease (one baby each). One case of pseudodeficiency for MPS I, 1 carrier for MPS I, 1 case of pseudodeficiency for Pompe disease and 1 carrier for Gaucher disease were identified. This report illustrates the challenges that may be encountered by NBS programs for LSDs, and the need of a comprehensive protocol for the rapid and precise investigation of the babies who have an abnormal screening result.