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

Abstract

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.