RESUMO
Objectives. To describe the results of a 16-year experience of a state-coverage expanded newborn screening program (NBSP) in Northeast México. Methods. Between 2002 and 2017, dried blood spots of newborns were screened for congenital hypothyroidism (CH), congenital adrenal hyperplasia (CAH), biotinidase deficiency, galactosemia, cystic fibrosis, and glucose-6-phosphate dehydrogenase (G6PD) deficiency via immunofluorescence and amino and fatty acid disorders and organic acidemias using tandem mass spectrometry. Frequency rates were determined. Results. Overall, 192 487 samples were processed; 99.4% had negative results, and 598 were diagnosed. The frequency was 3.01/1000 newborns. G6PD deficiency, CH, amino acidemia, organic acidemia, cystic fibrosis, CAH, fatty acid oxidation disorder, galactosemia, and biotinidase deficiency cases were 1:773, 1:962, 1:4277, 1:4476, 1:11,322, 1:10,693, 1:10,693, 1:38,497, and 1:64,162, respectively. Conclusion. Using different technologies in NBSP increased the number of conditions detected, facilitating infant morbidity and mortality prevention. The frequency of disorders depends on the population's genetic background and diagnostic capacity.
RESUMO
Aims: To explore the feasibility of detecting sex chromosome aneuploidies (SCAs) by means of gene copy number quantification of short stature homeobox (SHOX), vesicle-associated membrane protein 7 (VAMP7), and SRY in newborns. Materials and Methods: Gene doses of SHOX, VAMP7, and SRY were determined by quantitative polymerase chain reaction (qPCR) using DNA obtained from dried blood samples from newborns. Relative quantification values were obtained. An aneuploidy profile was established according to cutoff values. Samples with ≥2 gene doses (out of range) were reanalyzed, and those with aneuploidy profiles were confirmed by karyotyping. Sensitivity, specificity, and positive and negative predictive values were obtained. Results: A total of 10,033 samples were collected (4945 females and 5088 males). Of 244 (2.43%) samples with ≥2 gene doses that were retested, 20 cases were confirmed. The overall incidence of SCAs was 1 in 500 live newborns. There were six cases of Turner syndrome (1/824), 3 cases of XXX (1/1648), 7 cases of Klinefelter syndrome (1/726), and 4 cases of of XYY (1/1272). The sensitivity was 0.952 (95.42%); the specificity was 0.975 (97.56%); the positive predictive value was 0.909 (90.91%) and the negative predictive value was 0.987 (98.77%). Conclusions: Gene copy number analyses of the VAMP7, SHOX, and SRY genes by qPCR from blood samples spotted onto filter paper is a highly reliable method for the early detection of male and female SCAs.