The impact of neonatal 17-hydroxyprogesterone cutoff determination in a public newborn screening program for congenital adrenal hyperplasia in Southern Brazil: 3 years' experience.

Congenital adrenal hyperplasia (CAH) occurs due to enzyme defects in adrenal steroidogenesis. The 21-hydroxylase deficiency accounts for 90-95% of cases, triggering accumulation of 17-hydroxyprogesterone (17-OHP). Early diagnosis through neonatal screening allows adequate treatment and reduced mortality. The purpose of the study was to determine 17-OHP cutoffs for the diagnosis of CAH in a public newborn screening program in Southern Brazil. A retrospective, descriptive, cross-sectional study was conducted to analyze 17-OHP levels in dried blood samples collected on filter paper of 317,745 newborns screened at a public newborn screening center from May 2014 to April 2017. Neonatal 17-OHP was measured in DBS samples using a time-resolved fluoroimmunoassay (GSP® kit 3305-0010; PerkinElmer). Different cutoffs were determined and stratified by birth weight. The incidence of CAH was 1:15,887 live births in the state of Rio Grande do Sul, with 20 cases of classical CAH diagnosed during the study period. Most newborns (80.73%) were white, and the prematurity rate was 9.8% in the study population. The combination of different percentiles, 98.5th for birth weight 2001-2500 g and 99.8th for the other birth weight groups, decreased false-positive results and increased specificity compared with current reference values to identify classical CAH cases. The local 17-OHP cutoffs determined were higher than those currently used by this screening program for all birth weight groups. The calculation of reference values from local population data and the combination of percentiles proved to be a valuable tool for proper diagnosis of CAH and reduction in the number of false positives.

Evaluation of RET-He values as an early indicator of iron deficiency anemia in pregnant women

Abstract Introduction During pregnancy, women are at an increased risk of developing iron-deficiency anemia. Objective The objective of this study was to assess the diagnostic performance of the reticulocyte hemoglobin equivalent (RET-He) in the early detection of iron-deficiency anemia in a group of pregnant women and to establish a reference range for this parameter in a group of control individuals. Method: A total of 60 patients and 130 control subjects were included in the study. Blood samples collected from the subjects were submitted to a complete blood count and a serum ferritin test and the data were analyzed by comparing the groups and ROC curves. Results The reference range found for the RET-He was between 29.75pg and 38.24pg, with a median of 35pg. The receiver operating characteristic (ROC) curve analysis for the ferritin parameter showed an area under the curve of 0.732 for the RET-He, 0.586 for hemoglobin, 0.551 for the mean corpuscular hemoglobin concentration and 0.482 for the mean corpuscular volume. Conclusion Early diagnosis of iron deficiency anemia in pregnancy is essential to prevent damage to both maternal and fetal health. The RET-He presents an excellent potential as an auxiliary tool for the diagnosis of iron deficiency in pregnant women.

Epidemiological profile of congenital hypothyroidism at a southern Brazilian state

ABSTRACT Objective: To determine the incidence of congenital hypothyroidism (CH) over a 10-year period at the Reference Service in Neonatal Screening of the state of Rio Grande do Sul (RSNS-RS). Subjects and methods: Historical cohort study including all newborns screened for CH by the RSNS-RS from January 2008 until December 2017. Data of all newborns with neonatal TSH (neoTSH; heel prick test) values ≥ 9 mIU/L were collected. According to neoTSH values, the newborns were allocated into two groups: Group 1 (G1), comprising newborns with neoTSH ≥ 9 mIU/L and serum TSH (sTSH) < 10 mIU/L, and Group 2 (G2), comprising those with neoTSH ≥ 9 mIU/L and sTSH ≥ 10 mIU/L. Results: Of 1,043,565 newborns screened, 829 (0.08%) had neoTSH values ≥ 9 mIU/L. Of these, 284 (39.3%) had sTSH values < 10 mIU/L and were allocated to the G1 group, while 439 (60.7%) had sTSH ≥ 10 mIU/L and were allocated to the G2 group, and 106 (12.7%) were considered missing data. The overall incidence of CH was 42.1 per 100,000 newborns screened (95% confidence interval [CI] 38.5-45.7/100,000) or 1:2377 screened newborns. The sensibility and specificity of neoTSH ≥ 9 mIU/L were 97% and 11%; of neoTSH 12.6 mUI/L, 73% and 85% respectively. Conclusion: In this population, the incidence of permanent and transitory CH was 1:2377 screened newborns. The neoTSH cutoff value adopted during the study period showed excellent sensibility, which matters for a screening test.

Twenty Years of Neonatal Screening for Sickle Cell Disease in Brazil: The Challenges of a Continental Country with High Genetic Heterogeneity

Abstract Sickle cell disease (SCD) is the most common inherited hematological disease worldwide. The benefits of diagnosis and early intervention have led to the wide dissemination of public health programs worldwide. Through neonatal screening programs, it is possible to reduce morbidity and mortality in the first 5 years of life. The prophylactic use of penicillin, the anti-pneumococcal vaccine and other intensive care, increase the survival and quality of life of people with SCD. The aim of this study is to present the 20-year history of screening for hemoglobinopathies in Brazil and its challenges. From 2001 to 2019, an average of 2,400,000 children were screened per year nationwide, with the coverage being of 82,16%. The screening of 54,9% of newborns is collected up to their 5th day of life. The prevalence of SCD was 1:2,263 newborns; therefore, it was the second most-common disease detected by the program of Brazil, being only after hypothyroidism (1/2,175 live births). The healthcare system should provide the necessary infrastructure to confirm the diagnosis of newborns and to provide appropriate counseling and treatment. The early diagnosis and treatment, as well as the follow-up with a multidisciplinary team, are fundamental to the survival rate and the quality of life of patients.

Flow Cytometry in Detection of Fetal Red Blood Cells and Maternal F Cells to Identify Fetomaternal Hemorrhage.

Accurate detection and quantitation of fetomaternal hemorrhage (FMH) is critical to the obstetric management of rhesus D alloimmunization in Rh-negative pregnant women. The flow cytometry is based on the detection of fetal red blood cells using a monoclonal anti-HbF antibody, and is the method most indicated for this estimation. The objective of this study was to quantify fetal red blood cell levels of pregnant women using flow cytometry. We analyzed 101 peripheral blood samples from Rh-negative and Rh-positive women, whose mean age was 24 years (20-32 years), after vaginal delivery or cesarean section. Our study showed that 53% of pregnant women had fetal red blood cells levels <2.0 mL, 31% between 2.0-3.9 mL, 16% between 4.0-15.0 mL, and 1% >15.0 mL. Accurate quantitation of fetal red blood cells is necessary to determine the appropriate dose of anti-D (RHD) immunoglobulin to be administered to pregnant or postpartum women.

Evaluation of the Genetic Screening Processor for the Performance of Newborn Screening Tests

Abstract The collection of dried blood spots (DBSs) on filter paper has been a powerful tool in newborn screening (NBS) programs and in other fields. However, filter paper has been associated with some level of imprecision due to the filter paper matrix effect. In order to minimize measurement variations, these interferences should be evaluated by NBS assays. The aim of this study is to evaluate the performance of genetic screening processor (GSP) equipment in comparison with a widely used AutoDELFIA and to discuss the limitations and advantages of this new technology in NBS. We evaluated the performance of 3 NBS assays in DBS using GSP in comparison with AutoDELFIA. To determine the inaccuracy and the intra-assay precision, a comparative study and a replication experiment were performed. In the comparative study, human thyroid-stimulating hormone (hTSH) assay showed the highest correlation coefficient, followed by 17α-OH-progesterone and immunoreactive trypsinogen (IRT) assays. The results of the present study suggest that the GSP equipment and kits are suitable for implementation and have acceptable performance for NBS routine. Genetic screening processor assay tends to underestimate hTSH and IRT concentrations in the clinically relevant range when compared to AutoDELFIA assays. More studies are necessary to reevaluate cutoff values. Furthermore, the equipment has advantages when compared with AutoDELFIA, such as methodology with more specificity, reduction in the processing time, and randomized routine. This helps promoting faster dynamic technical processes and faster report generation.

Diagnóstico laboratorial das leucemias linfóides agudas / In vitro diagnosis of acute lymphoid leukemias

A leucemia linfóide aguda (LLA) é a forma mais comum de câncer na infância, compreendendo 70 por cento dos casos; em adultos a incidência é de apenas 20 por cento. A abordagem inicial do diagnóstico consiste no exame citomorfológico do sangue periférico e da medula óssea. O estudo imunofenotípico eleva para 99 por cento o percentual de casos corretamente classificados, permitindo identificar a linhagem celular (T ou B) e os diferentes estágios de maturação da célula. Aproximadamente 20 por cento dos casos são de origem de célula T; 75 por cento, precursores de célula B; e 5 por cento, de célula B madura. As técnicas citogenéticas têm contribuído de maneira fundamental para a compreensão da biologia molecular e do tratamento da LLA. As anormalidades cromossômicas, quando associadas ao painel de imunofenotipagem, constituem o parâmetro mais importante para a classificação das leucemias, e, juntamente com outros fatores clínicos e laboratoriais, possibilitam a estratificação dos pacientes em diferentes grupos de risco, tendo importância fundamental para determinar o prognóstico e estabelecer o tratamento adequado. O objetivo deste trabalho é fazer uma revisão bibliográfica dos métodos laboratoriais através dos critérios morfológicos, citoquímicos, imunológicos, citogenéticos e de genética molecular, que são úteis para a classificação e o diagnóstico das leucemias linfóides agudas.