Letter to Editor Leonardo Ferreira Soares Oneide Angélica Monteiro dos Santos Rocha Evaldo Hipólito de Oliveira José Felipe Pinheiro do Nascimento Vieira Universidade Federal do Piauí - UFPI, Teresina, PI, Brazil Neonatal screening in the state of Piauí: an urgent need - a study on the prevalence of sickle cell disease in newborns Conflict-of-interest disclosure: The authors declare no competing financial interest Submitted: 7/12/2012 Accepted: 7/18/2012 Corresponding author: Leonardo Ferreira Soares Av Duque de Caxias, 2960 Apto 201B 64000-000 Teresina, PI, Brazil leonardosoares@hotmail.com www.rbhh.org or www.scielo.br/rbhh DOI: 10.5581/1516-8484.20120096 392 Regarded as the most prevalent genetic disease in the world, the frequency of sickle cell anemia is estimated at between 25% and 40% in African countries. In the field of public health, the emphasis on sickle cell anemia as an ethnical-racial disease is based on three aspects related to this pathology which characterize a greater susceptibility of the black and mulatto populations: geographical origin, genetic etiology and statistics on prevalence(1-3). Sickle cell disease involves a series of different genetic alterations that cause from minor to serious symptoms and a high mortality rate. Hemoglobin S (Hb S) is a mutation of the β-globin gene with the exchange of a nitrogen base at position 6, whereby glutamic acid (GAG) is replaced by valine (GTG), resulting in the expression of the βs gene and a structural change in its function. In 2001, the Ministry of Health decree N° GM/MS Nº 822 established the National Neonatal Screening Program (PNTN) that made the diagnosis, treatment and monitoring of sickle cell disease and other hemoglobinopathies obligatory throughout the country. According to PNTN data around 3000 children per year are born in Brazil with sickle cell disease and 180,000 have the sickle cell trait. The disease in Brazil is distributed heterogeneously with an incidence of 0.3% of the population; however, in part due to the poor social profile(1), there is a high prevalence in the northeastern region, chiefly in the states of Bahia, Maranhão and Piauí, where the proportion of African descendants is higher(4,5). It is of great concern that the state of Piauí, the home to the earliest traces of life in the Americas and registered as the state with the fourth highest self-declared black population, has no indicators in relation to the genetic inheritance of hemoglobin S in newborn babies. As such, a study was performed to provide support for the implementation of phase II of the newborn screening test, thereby strengthening and consolidating the Sickle Cell Disease Program in the state of Piauí. The ethical aspects of the study were approved by the Research Ethics Committee of the Universidade Federal do Piauí (# 0181.0.045.00008). Table 1 - Variant hemoglobins in newborns and maternal ethnicity in the city of Teresina, PI in 2008-2009 Variant Hb Hb FS Hb FAS Hb FAC Hb FAD Hb FA Others Total Nº 5 39 9 2 974 5 1034 Black 0.5 3.8 0.9 0.2 94.0 0.5 100.0 Ethnicity (%) Mulatto 0.6 3.6 0.9 0.2 94.0 0.6 100.0 White 0.0 5.0 0.7 0.0 94.0 0.3 100.0 unknown 0.0 6.0 0.0 0.0 94.0 0.0 100.0 Hb FS: homozygous for hemoglobin S; Hb FAS: sickle cell trait; Hb FAC: hemoglobin C trait; Hb FAD: hemoglobin D trait; Hb FA: normal hemoglobin Table 2 - Percentage of variant hemoglobins in newborns in northeastern capital cities City Teresina (PI) Salvador (BA)(6) Natal (RN)(7) Fortaleza (CE)(8) Recife (PE)(11) João Pessoa (PB)(10) Total Sample 1034 590 1903 389 1998 1006 Hb FAS (%) 3.8 9.8 1.5 3.8 5.1 0.2 Hb FS: homozygous for hemoglobin S; Hb FAS: sickle cell trait Hb FS (%) 0.5 0.2 0.05 0.2 0.2 - Year of survey 2008-2009 2000 2001 2001-2002 1996-1997 1993 Rev Bras Hematol Hemoter. 2012;34(5):392-3