Overweight/obesity in adolescents with phenylketonuria: protective and predisposing factors

Abstract Objective: To estimate the prevalence and factors associated with overweight/obesity development in adolescents with early diagnosed phenylketonuria treated exclusively by diet. Methodology: In this cross-sectional study anthropometric measurements, serum phenylalanine levels, and 10 metabolites associated with lipid and carbohydrate metabolism were analyzed in 101 adolescents aged 10-20 years. Adolescents were categorized into overweight/obesity and eutrophic/low body mass index groups. These patients were compared using Student's t-test, Pearson's chi-square test, Wald's chi-square test for multivariate analysis. Further, to verify whether the prevalence of overweight/obesity found in the study population was similar to that in the general population, the authors compared the nutritional status of 46 patients aged 13-17 years with that of healthy students of the same age from the National School Health Survey using the chi-square test for adherence. The significance threshold was p < 0.5. Results: The prevalence of overweight/obesity in adolescents was 27.7%. There was no difference in prevalence between sexes. Older age was a protective factor and Increased Homeostasis Model Assessment Insulin Resistance index and high phenylalanine and low-density lipoprotein cholesterol levels were predictive factors for overweight/obesity. The equality hypothesis was not rejected in the comparison of nutritional states of 46 patients aged 13-17 years and healthy students of the same age. Conclusion: The prevalence of overweight/obesity in phenylketonuria adolescents was similar to what is found in healthy adolescents.

Metabolic control and body composition of children and adolescents with phenylketonuria / Controle metabólico e composição corporal de crianças e adolescentes com diagnóstico neonatal de fenilcetonúria

ABSTRACT Objective: To characterize metabolic control and verify whether it has any relation with socioeconomic, demographic, and body composition variables in children and adolescents with phenylketonuria (PKU) diagnosed in the neonatal period. Methods: This cohort study collected retrospective data of 53 phenylketonuric children and adolescents. Data on family income, housing, and mother's age and schooling level were collected, and anthropometric measures of body composition and distribution were taken. All dosages of phenylalanine (Phe) from the last five years (2015-2019) were evaluated and classified regarding their adequacy (cutoffs: 0-12 years: 2-6 mg/dL; 12-19 years: 2-10 mg/dL). Adequate metabolic control was considered if ≥7%) of the dosages were within desired ranges. Results: The mean (±standard deviation) age in the last year was 10.1±4.6 years. Most of them were under 12 years old (33/53; 62.3%) and had the classic form of the disease (39/53; 73.6%). Better metabolic control was observed among adolescents (68.4 versus 51.4%; p=0.019). Overweight was found in 9/53 (17%) and higher serum Phe levels (p<0.001) were found in this group of patients. Metabolic control with 70% or more Phe level adequacy decreased along with the arm muscle area (AMA) (ptendency=0.042), being 70.0% among those with low reserve (low AMA), and 18.5% among those with excessive reserve (high AMA). Conclusions: Adequate metabolic control was observed in most patients. The findings suggest that, in this sample, the levels of phenylalanine may be related to changes in body composition.

RESUMO Objetivo: Caracterizar o controle metabólico e verificar se existe relação entre ele, variáveis socioeconômicas, demográficas e composição corporal de crianças e adolescentes com fenilcetonúria (FNC) diagnosticada no período neonatal. Métodos: Coorte com coleta retrospectiva de dados de 53 crianças e adolescentes fenilcetonúricos. Foram coletados dados de renda familiar, moradia, idade e escolaridade materna e realizaram-se medidas antropométricas de composição e distribuição corporal. Todas as dosagens de fenilalanina (Fal) dos últimos cinco anos (2015-2019) foram avaliadas e classificadas quanto à adequação (cortes: 0-12 anos: 2-6 mg/dL; 12-19 anos: 2-10 mg/dL). A proporção de dosagens adequadas ≥70% foi considerada como controle metabólico adequado. Resultados: A média (±desvio padrão) de idade, no último ano, foi de 10,1±4,6 anos. A maioria tinha menos de 12 anos (33/53; 62,3%) e apresentava a forma clássica da doença (39/53; 73,6%). Observou-se melhor controle metabólico entre os adolescentes (68,4 vs. 51,4%; p=0,019). Excesso de peso foi encontrado em 9/53 (17%) e maiores níveis séricos de Fal foram descritos nesse grupo (p<0,001). O percentual de controle metabólico com 70% ou mais de adequação dos níveis de Fal foi decrescente de acordo com a área muscular do braço (AMB; ptendência=0,042), sendo de 70% entre os de baixa reserva (AMB reduzida) e de 18,5% entre os com excesso (AMB elevada). Conclusões: Observou-se controle metabólico adequado na maioria dos avaliados e os achados sugerem que, nesta amostra, os níveis de fenilalanina podem estar relacionados com alterações da composição corporal.

BH4 deficiency identified in a neonatal screening program for hyperphenylalaninemia / Deficiências de BH4identificadas em um programa de triagem neonatal para hiperfenilalaninemias

Abstract Objectives To show the general prevalence and to characterize tetrahydrobiopterin (BH4) deficiencies with hyperphenylalaninemia, identified by the Neonatal Screening Program of the State of Minas Gerais. Methods Descriptive study of patients with BH4 deficiency identified by the Neonatal Screening Program of the State of Minas Gerais. Results The prevalence found was 2.1 for 1,000,000 live births, with a frequency of 1.71% among hyperphenylalaninemias. There were four cases (40%) with 6-pyruvoyl-tetrahydropterin synthase deficiency, three with GTP cyclohydrolase I - autosomal recessive form deficiency, and three with dihydropteridine reductase deficiency (30% each). Six patients were diagnosed due to clinical suspicion and four cases due to systematic screening in neonatal screening. After the start of the treatment, patients identified by neonatal screening had rapid improvement and improved neuropsychomotor development compared to those diagnosed by the medical history. Conclusions The prevalence of BH4 deficiencies in Minas Gerais was slightly higher than that found in the literature, but the frequency among hyperphenylalaninemias was similar. Although rare, they are severe diseases and, if left untreated, lead to developmental delays, abnormal movements, seizures, and premature death. Early treatment onset (starting before 5 months of age) showed good results in preventing intellectual disability, justifying the screening of these deficiencies in newborns with hyperphenylalaninemia identified at the neonatal screening programs for phenylketonuria.

Resumo Objetivos Apresentar a prevalência geral e caracterizar as deficiências de tetrahidrobiopterina - BH4 - com hiperfenilalaninemia, identificadas pelo Programa de Triagem Neonatal do Estadode Minas Gerais. Métodos Estudo descritivo de pacientes com deficiência de BH4 do Programa de Triagem Neonatal do Estado de Minas Gerais. Resultados A prevalência encontrada foi de 2,1 para 1.000.000 recém-nascidos vivos e a frequência de 1,71%, dentre as hiperfenilalaninemias. Quatro casos (40%) com deficiência de 6-piruvoil-tetrahidropterina sintase, três com deficiência de GTP ciclohidrolase I e três com deficiência de dihidropteridina redutase (30% cada um). Seis pacientes foram diagnosticadospor suspeita clínica e quatro pela pesquisa sistemática na triagem neonatal. Após o início do tratamento, os pacientes identificados pela triagem neonatal tiveram melhora rápida e melhor desenvolvimento neuropsicomotor em comparação com aqueles diagnosticados pela história clínica. Conclusões A prevalência das deficiências de BH4 em Minas Gerais foi um pouco maior que a encontrada na literatura, mas a frequência, entre as hiperfenilalaninemias, foi semelhante. Embora raras, são graves e, se não tratadas, levam a atraso de desenvolvimento, movimentos anormais, convulsões e morte precoce. O tratamento precoce (início antes dos 5 meses) mostrou bons resultados na prevenção de deficiência intelectual, justificando a pesquisa dessas deficiências nos recém-nascidos com hiperfenilalaninemia pelos programas de triagem neonatalpara fenilcetonúria.

Assessment of newborn screening in the public health system of a municipality in northern Rio Grande do Sul

Introduction: Newborn screening allows the screening of diseases that are still in the asymptomatic period and whose early diagnosis and treatment are associated with reduced infant morbidity and mortality. The aim of this study was to evaluate the public National Newborn Screening Program in the municipality of Carazinho, state of Rio Grande do Sul (RS), Brazil. Methods: This was a population-based, retrospective, descriptive study. We collected and transcribed data from a database of the Carazinho municipal laboratory, which is affiliated with the referral center for newborn screening in RS. The records of all individuals undergoing newborn screening from 2005 to 2010 were reviewed, and information was collected on the program coverage, time elapsed between birth and screening (first collection), and test results. Results: The program had a coverage of 75.5%. One suspected case of phenylketonuria, three suspected cases of congenital hypothyroidism and no suspected cases of hemoglobinopathy were identified. In addition, there were 18 positive results for hemoglobin S heterozygosity, five for hemoglobin D heterozygosity, two for hemoglobin C heterozygosity, and one for a rare variant hemoglobin. When analyzing the newborn's age at the time of blood collection, it was observed that 63.1% were within the recommended age range. Conclusions: Our findings suggest the need for optimization of public newborn screening in the evaluated municipality. The strategies to be adopted should include education of the population and especially of managers and health professionals about the importance of newborn screening. (AU)

Evaluation of effectiveness and outcome of PKU screening and management in the State of Sergipe, Brazil / Avaliação da eficiência e desfecho da triagem e manejo da PKU no Estado de Sergipe, Brasil

Objectives: Phenylketonuria (PKU) was the first inherited metabolic disease known to cause mental retardation for which a newborn screening program (NBS) was developed. The objective of this study was to evaluate the effectiveness of PKU NBS and the management of cases in the northeastern Brazilian state of Sergipe (SE).Materials and methods: We reviewed the phenylalanine concentrations in filter-paper collected from the heel (PKUneo) of 43,449 newborns; blood concentrations obtained by venipuncture in the subjects with abnormal PKUneo; the children’s age at several phases of the program, the incidence of the disease from January 2007 to June 2008; and metabolic control of the patients.Results: The coverage of NBS/SE was 78.93%. The children’s age was 10 ± 7 days at PKUneo collection. Twelve children were recalled based on the PKUneo cutoff value at 28 ± 13 days. From these, the concentrations of phenylalanine collected by venipuncture were normal in five children. The incidence of hyperphenylalaninemia was 1/43,449, and of PKU was 1/8,690 (5 cases). One suspected subject died. Another death occurred in the cohort, in a confirmed PKU case. PKU treatment began within 51 ± 12 days of life. In the four patients under dietary phenylalanine restriction, metabolic control was often difficult.Conclusions: PKU NBS/SE has satisfactory coverage and adequate cutoff for recalling patients and diagnosis, but the onset of treatment is delayed, and follow-up metabolic control is frequently inadequate.

Objetivos: A fenilcetonúria (PKU) foi a primeira causa metabólica hereditária de retardamento mental para a qual foi desenvolvido um programa de triagem em recém-nascidos (NBS). O objetivo deste estudo foi avaliar a eficácia do NBS para a PKU e o manejo dos casos em Sergipe (SE), Brasil.Materiais e métodos: Revisamos as concentrações de fenilalanina no filtro de papel coletado do calcanhar (PKUneo) de 43.449 recém-nascidos, suas concentrações de sangue obtidas por punção venosa em indivíduos com PKUneo anormal, a idade das crianças em diversas fases do programa, a incidência da doença no período de janeiro de 2007 a junho de 2008 e o controle metabólico dos pacientes.Resultados: A cobertura da NBS/SE foi de 78,93%. A idade das crianças era de 10 ± 7 dias na coleta de PKUneo. Doze crianças foram reconvocadas com base no ponto de corte de PKUneo aos 28 ± 13 dias de idade. Destas, as concentrações de fenilalanina por venipunctura foram normais em cinco. A incidência da hiperfenilalaninemia foi 1/43.449 e de PKU foi 1/8.690 (5 casos), e um indivíduo suspeito foi a óbito. Outro óbito ocorreu na coorte em um caso de PKU confirmado. O tratamento para a PKU começou com 51 ± 12 dias. Nos quatro pacientes sob restrição de fenilalanina alimentar, o controle metabólico foi frequentemente difícil.Conclusões: PKU NBS/SE apresenta uma cobertura satisfatória e ponto de corte adequado para reconvocação e diagnóstico, mas o início do tratamento é atrasado e o controle no seguimento é frequentemente inadequado.

The proportion of tetrahydrobiopterin deficiency and PAH gene deficiency variants among cases with hyperphenyalaninemia in Western Iran.

BACKGROUND: Defects either in phenylalanine hydroxylase (PheOH) or in the production and recycling of its cofactor (tetrahydrobiopterin [BH4]) are the causes of primary hyperphenylalaninemia (HPA). The aim of our study was to investigate the current status of different variants of HPA Kurdish patients in Kermanshah province, Iran. MATERIALS AND METHODS: From 33 cases enrolled in our study, 32 were identified as HPA patients. Reassessing of pre‑treatment phenylalanine concentrations and the analysis of urinary pterins was done by high‑performance liquid chromatography method. RESULTS: A total of 30 patients showed PAH deficiency and two patients were diagnosed with BH4 deficiency (BH4/ HPA ratio = 6.25%). Both of these two BH4‑deficient patients were assigned to severe variant of dihydropteridine reductase (DHPR) deficiency. More than 75% of patients with PAH deficiency classified as classic phenylketonuria (PKU) according their levels of pre‑treatment phenylalanine concentrations. CONCLUSION: Based on the performed study, we think that the frequency of milder forms of PKU is higher than those was estimated before and/or our findings here. Furthermore, the frequency of DHPR deficiency seems to be relatively high in our province. Since the clinical symptoms of DHPR deficiency are confusingly similar to that of classic PKU and its prognosis are much worse than classical PKU and cannot be solely treated with the PKU regime, our pilot study support that it is crucial to set up screening for BH4 deficiency, along with PAH deficiency, among all HPA patients diagnosed with HPA.

Prevalência de patologias detectadas pela triagem neonatal em Santa Catarina / Prevalence of disorders detected by newborn screening in Santa Catarina

OBJETIVO: Avaliar a prevalência das patologias fenilcetonúria (FNC), hipotireoidismo congênito (HC), fibrose cística (FC), hemoglobinopatias (HB) e hiperplasia adrenal congênita (HAC), no Estado de Santa Catarina, a fim de delinear o perfil da população catarinense em relação a essas patologias. MATERIAIS E MÉTODOS: Foi realizado um levantamento de dados do Programa de Triagem Neonatal da Secretaria de Estado da Saúde de Santa Catarina, no período de 2004 a 2008. RESULTADOS: No período de estudo, foram obtidas as seguintes prevalências: FCN 1:28.862, HC 1:2.876, FC 1:5.121, HB S 1:14.446 e para HAC 1:11.655 crianças triadas. CONCLUSÕES: A prevalência média da FNC mostrou-se inferior à prevalência nacional, ao passo que a da HAC foi superior; por sua vez, a do HC mostrou-se semelhante às prevalências mundial e nacional. Além disso, o predomínio da população caucasiana no Estado resultou em uma prevalência reduzida da HB e uma prevalência aumentada da FC em relação ao restante do país.

OBJECTIVE: To evaluate the prevalence of the diseases phenylketonuria (PKU), congenital hypothyroidism (CH), cystic fibrosis (CF), hemoglobinopathies (HB), and congenital adrenal hyperplasia (CAH), in the state of Santa Catarina, in order to delineate the local population profile for these diseases. MATERIALS AND METHODS: A survey of data from the Newborn Screening Program of the Ministry of Health of Santa Catarina, in the period 2004 to 2008 was carried out. RESULTS: During the study period, the following prevalences were obtained: 1:28,862 children screened for PKU; 1:2,876 children screened for CH; 1:5,121 children screened for CF; 1:14,446 children screened for HB S; and 1:11,655 children screened for CAH. CONCLUSIONS: The prevalence of PKU proved to be lesser than the national prevalence, while CAH prevalence was greater. On the other hand CH prevalence was similar to the global and national prevalence. Moreover, the predominance of the Caucasian population in the state resulted in reduced prevalence of HB S and increased prevalence of CF in relation to the rest of the country.

Evolução do programa de triagem neonatal no estado do Tocantins / Evolution of the neonatal screening program in the state of Tocantins

OBJETIVO: Avaliar o Programa de Triagem Neonatal do Estado do Tocantins de 1995 a 2011. MATERIAIS E MÉTODOS: A coleta de dados foi realizada por meio de entrevista com os responsáveis pelo serviço, por análise de prontuários de pacientes com diagnóstico de fenilcetonúria (PKU) ou hipotireoidismo congênito (HC) atendidos pelo programa e por entrevista com pais e/ou responsáveis por pacientes em acompanhamento. RESULTADOS: A cobertura de triagem neonatal aumentou de 32,3% para 76,6% depois da implantação do Programa Nacional de Triagem Neo­natal (PNTN). A prevalência de PKU e de HC no período analisado foi de 1:28.309 e de 1:4.632 nascidos vivos, respectivamente. A idade média das crianças na coleta da primeira amostra de sangue (PKU: 9,6 ± 6,3 dias; HC: 13,3 ± 10,3 dias) e no início do tratamento (PKU: 57,0 ± 17,6 dias; HC: 95,6 ± 57,6 dias) foi superior às preconizadas pelo Ministério da Saúde. A avaliação dos pais sobre a qualidade do acompanhamento realizado foi classificada como satisfatória por 100% dos entrevistados. CONCLUSÃO: Embora tenha havido grande evolução do programa de triagem neonatal deste Estado, há necessidade de maior incentivo governamental para que o programa seja otimizado e possa avançar para as fases seguintes do PNTN.

OBJECTIVE: To evaluate the Neonatal Screening Program in the State of Tocantins from 1995 to 2011. MATERIALS AND METHODS: Data collection was conducted by means of interviews with those responsible for the service, by the analysis of medical records of patients diagnosed with phenylketonuria (PKU) and congenital hypothyroidism (CH) that were enrolled in the program, and by interviews with parents and/or guardians of the patients monitored. RESULTS: Program coverage increased from 32.3% to 76.6% after the implementation of the National Newborn Screening Program (PNTN). The prevalence of PKU and CH was 1:28,309 and 1:4,632 live births, respectively. The mean ages at the collection of the first blood sample (PKU: 9.6 ± 6.3 days; CH: 13.3 ± 10.3 days) and at the beginning of the treatment (PKU: 57.0 ± 17.6 days; CH: 95,6 ± 57.6 days) were greater than recommended by the Ministry of Health. The quality of monitoring was considered satisfactory by 100% of the parents. CONCLUSION: Although there have been great developments in neonatal screening program in this state, there is need for greater government incentives to optimize the program and to make the PNTN advance to its next phases.

Phenylketonuria, congenital hypothyroidism and haemoglobinopathies: public health issues for a Brazilian newborn screening program / Fenilcetonúria, hipotireoidismo congênito e hemoglobinopatias: questões de saúde pública para um programa de triagem neonatal brasileiro

In this study, the frequency of detected congenital hypothyroidism, phenylketonuria and haemoglobinopathies in the State of Rio de Janeiro's (Brazil) Newborn Screening Program (NBSP) was analyzed between the years of 2005 and 2007. There were two Newborn Screening Reference Centers (named NSRC A and B) with programmatic differences. In 2007, overall detection coverage reached 80.7%. The increase in the incidence of congenital hypothyroidism (1:1,030 in 2007) was attributed to the reduction of neonatal TSH value limits over time. The incidence discrepancy of phenylketonuria between NSRC A (1:28,427) and B (1:16,522) might be partially explained by the small number of cases. The incidence of sickle cell disease and its traits were uniformly high (1:1,288 and 1:21, respectively). This was coherent with the ethnic composition of the population. The differences in laboratory methods and critical values, in addition to other programmatic issues, may explain the variances in the results and limited analysis of the role of biological and environmental determinants in the occurrence of these diseases.

Neste estudo, foi analisada a frequência de detecção do hipotireoidismo congênito, fenilcetonúria e hemoglobinopatias no Programa de Triagem Neonatal do Estado do Rio de Janeiro, Brasil, entre 2005 e 2007. Havia dois Serviços de Referência em Triagem Neonatal (designados SRTN A e B) com diferenças programáticas. Em 2007, a cobertura alcançou 80,7%. O aumento na incidência do hipotireoidismo congênito (1:1.030 em 2007) foi atribuído à redução no valor de corte do TSH ao longo do tempo. As incidências discrepantes da fenilcetonúria entre os modelos (SRTN A - 1:28.427; SR-TN B - 1:16.522) podem ser parcialmente explicadas pelo pequeno número de casos. A incidência da doença falciforme e do traço falcêmico foi uniformemente elevada (1:1.288 e 1:21, respectivamente), sendo coerente com a composição étnica da população. As diferenças nos métodos laboratoriais e valores críticos, além de outras questões programáticas, podem explicar a variabilidade nos resultados e limitar a análise do papel dos determinantes biológicos e ambientais sobre a ocorrência das doenças.

Triagem neonatal para hiperfenilalaninemia: um estudo de coorte / Newborn screening for hyperphenylalaninemia: a cohort study

Introdução: A Fenilcetonúria Clássica é causada pela deficiência da enzima hepática fenilalaninahidroxilase. Se não diagnosticada e tratada precocemente, causa retardo mental. O objetivo deste estudo foi identificar indivíduos submetidos à triagem neonatal no Rio Grande do Sul entre 1986 e 2003, com teste positivo para hiperfenilalaninemia, estimar a prevalência de hiperfenilalaninemias, verificar níveis de controle e correlacionar os anos de realização do teste, início do tratamento, evolução e quadro clínico. Métodos: Casos de hiperfenilalaninemia foram identificados nos laboratórios e clínicas de tratamento. Foi aplicado questionário, contendo variáveis demográficas e sobre a patologia, o desenvolvimento infantil, a escolaridade, o aconselhamento genético e o rastreamento neonatal. Foram avaliados pacientes entre 6 meses e 16 anos de idade. Na análise estatística, utilizou-se o teste do qui-quadrado e ANOVA para avaliar a associação entre ano do diagnóstico e controle de fenilalanina e regressão logística para avaliar o efeito conjunto de idade do diagnóstico e controle de fenilalanina sobre o atraso no desenvolvimento. Resultados: De 1986 a 2003, 418 crianças apresentaram teste positivo para fenilalanina. Destes, 351 (84,0%) apresentaram resultados normais na segunda amostra, 58 (13,9%) foram considerados portadores de hiperfenilalaninemia e 9 (2,1%) tiveram o seguimento perdido. A cobertura do programa foi de 50%. Sobre o aconselhamento genético, 39 entrevistados (72,2%) responderam não saber, não lembrar ou deram respostas incorretas. Conclusão: Não se observou tendência histórica do diagnóstico ter se tornado mais precoce ou do controle laboratorial ter se tornado melhor. O controle bioquímico da fenilalanina não dependeu da precocidade do diagnóstico e sim, da idade dos pacientes.

Introduction: Classical phenylketonuria is caused by deficiency of the hepatic enzyme phenylalanine hydroxylase. If not diagnosed and treated early, it causes mental retardation. The aim of this study was to identify patients who underwent neonatal screening in Rio Grande do Sul between 1986 and 2003 and tested positive for hyperphenylalaninemia, to estimate the prevalence of hyperphenyl-alaninaemias, to check the levels of control, and to correlate the years of testing, initiation of treatment, evolution and clinical picture. Methods: Cases of hyperphenylalaninemia were identified in laboratories and treatment clinics. A questionnaire was administered containing demographic variables and about the pathology, child development, education, genetic counseling and neonatal screening. We evaluated patients between 6 months and 16 years of age. The statistical analysis used the chi-square test and ANOVA to assess the association between year of diagnosis and control of phenylalanine and logistic regression to assess the combined effect of age at diagnosis and control of phenylalanine on the developmental delay. Results: From 1986 to 2003, 418 children tested positive for phenylalanine. Of these, 351 (84.0%) had normal results in the second sample, 58 (13.9%) were considered with hyperphenylalaninemia, and 9 (2.1%) were lost for follow-up . The coverage of the program was 50%. Concerning genetic counseling, 39 respondents (72.2%) reported not knowing, not remembering or gave incorrect answers. Conclusion: There was no historical trend of diagnosis having become earlier or of laboratory control having improved. The biochemical control of phenylalanine was dependent on patient age rather than on early diagnosis.

Aspectos clínicos e demográficos da fenilcetonúria no Estado da Bahia / Clinical and demographic aspects of phenylketonuria in Bahia State, Brazil

OBJETIVO:Descrever as características clínicas e demográficas dos pacientes com diagnóstico de hiperfenilalaninemia acompanhados no Serviço de Referência em Triagem Neonatal da Bahia. MÉTODOS: Estudo transversal de 99 famílias (111 afetados) com fenótipo bioquímico de hiperfenilalaninemia, com coleta de dados em prontuários e em banco de dados laboratorial, incluindo aspectos demográficos e clínicos. RESULTADOS: A incidência de hiperfenilalaninemia na Bahia foi de um caso a cada 16.334 nascidos vivos, com cobertura de 91 por cento. Dentre os pacientes acompanhados, 82 por cento foram diagnosticados pela triagem neonatal e, em 11 famílias, havia mais de um caso. O fenótipo clássico da fenilcetonúria foi diagnosticado em 63 (57 por cento) pacientes. Entre os triados, a mediana de idade na primeira consulta foi 39,5 dias e, deles, 34 por cento apresentavam sintomatologia nesse momento; nenhum com atraso no desenvolvimento neuropsicomotor. A consanguinidade foi descrita em 32 por cento dos casos e houve predomínio de pacientes classificados como brancos (63 por cento). Os pais tinham baixa escolaridade e baixa renda. Dos 417 municípios da Bahia, 15 por cento apresentavam pelo menos um caso, com concentração na região nordeste (10 por cento) e na capital do Estado (14 por cento). CONCLUSÕES: Os resultados evidenciaram idade tardia ao início do tratamento, o que pode comprometer os resultados do programa. Observou-se também presença de consanguinidade e recorrência familiar, reforçando a importância da investigação familiar para diagnosticar indivíduos com deficiência mental de etiologia não esclarecida que podem se beneficiar de tratamento.

OBJECTIVE:To describe demographic and clinical characteristics of patients with hyperphenylalaninemia followed at the Neonatal Screening Reference Service of Bahia, Brazil. METHOD:Cross-sectional study including 99 families (111 affected individuals) with biochemical phenotype of hyperphenylalaninemia by chart review and laboratory database that include demographic and clinical features. RESULTS: The incidence of hyperphenylalaninemia in Bahia was one case per 16,334 live births, covering 91 percent of them. Among patients followed, 82 percent were diagnosed by newborn screening and, in 11 families, there were more than one case. The classic phenotype of phenylketonuria was diagnosed in 63 (57 percent) patients. Among those screened, the median age at first consultation was 39.5 days. Among the patients, 34 percent had symptoms at the first medical consultation, none of them with delayed neurodevelopment. Consanguinity was reported in 32 percent of patients. Affected individuals were predominantly classified as white (63 percent). The parents had low education and low income. Among the 417 municipalities of Bahia, 15 percent had at least one case, with a concentration in the Northeast (10 percent) and in the capital of the State (14 percent). CONCLUSIONS: The results showed elevated age at the beginning of the treatment, which may compromise the program results. Presence of consanguinity and familial recurrence were also noted. Careful investigation of families searching for individuals with mental retardation of unknown etiology that would benefit from the treatment is important.

Análise das prevalências de doenças detectadas pelo programa nacional de triagem neonatal no município de Araraquara no ano de 2009 / Prevalence analysis of diseases detected by the National Neonatal Screening Program in Araraquara city (Brazil) in the year 2009

O Programa Nacional de Triagem Neonatal (PNTN) implantado no Brasil tem como objetivo, considerando cada fase de execução local, detectar doenças como fenilcetonúria, hipotereoidismo congênito, hemoglobinopatias e fibrose cística. O objetivo deste trabalho foi analisar, através de um estudo transversal e observacional, a prevalência das doenças detectadas pelo PNTN no município de Araraquara emitidas pela APAE de São Paulo no período compreendido entre abril e dezembro de 2009. Os resultados mostram que o município apresentou, no ano de 2009, prevalência de fenilcetonúria e hipotireoidismo congênito de 0,06% acima da média nacional, que é de 0,01% e 0,03%, respectivamente. Com relação às hemoglobinopatias, encontrou-se prevalência do traço para anemia falciforme de 2,15% abaixo da média nacional, que é de 2,6%. A prevalência do traço C no município foi de 0,57%, semelhante a valores nacionais disponíveis na literatura. FA BART´S confirmado apresentou valor de 0,13% abaixo da média de 0,38% da região do município de Araraquara. A realização do teste do pezinho e o aconselhamento aos cuidadores são fatores importantes para redução de morbidades relacionadas à evolução dessas doenças.

The National Neonatal Screening Program (NNSP) set up in all Brazil, aims, through planned phases of local implementation, to detect diseases such as phenylketonuria, congenital hypothyroidism, hemoglobinopathies and cystic fibrosis. The aim of this study was to assess, through a cross-sectional observational study, the prevalence of the diseases detected by the NNSP in the city of Araraquara, in records issued by the São Paulo APAE laboratory in the period between April and December 2009.The results show that Araraquara had a prevalence of phenylketonuria and congenital hypothyroidism 0.06% above the national averages of 0.01% and 0.03% respectively. With respect to hemoglobinopathies, the prevalence of sickle cell trait was 2.15% below the national average of 2.6%. The prevalence of Hb C in the city was 0.57%, similar to national values reported in the literature. Confirmed Hb Bart´s had a prevalence of 0.13% in Araraquara, below the average of 0.38% for the surrounding region. The neonatal screening by heel-prick test and counseling for caregivers are important factors in reducing morbidity related to the evolution of these diseases.

Exon deletions of the phenylalanine hydroxylase gene in Italian hyperphenylalaninemics

A consistent finding of many studies describing the spectrum of mutant phenylalanine hydroxylase (PAH) alleles underlying hyperphenylalaninemia is the impossibility of achieving a 100% mutation ascertainment rate using conventional gene-scanning methods. These methods include denaturing gradient gel electrophoresis (DGGE), denaturing high performance liquid chromatography (DHPLC), and direct sequencing. In recent years, it has been shown that a significant proportion of undetermined alleles consist of large deletions overlapping one or more exons. These deletions have been difficult to detect in compound heterozygotes using gene-scanning methods due to a masking effect of the non-deleted allele. To date, no systematic search has been carried out for such exon deletions in Italian patients with phenylketonuria or mild hyperphenylalaninemia. We used multiplex ligation- dependent probe amplification (MLPA), comparative multiplex dosage analysis (CMDA), and real-time PCR to search for both large deletions and duplications of the phenylalanine hydroxylase gene in Italian hyperphenylalaninemia patients. Four deletions removing different phenylalanine hydroxylase (PAH) gene exons were identified in 12 patients. Two of these deletions involving exons 4-5-6-7-8 (systematic name c.353-?_912 + ?del) and exon 6 (systematic name c.510-?_706 + ?del) have not been reported previously. In this study, we show that exon deletion of the PAH gene accounts for 1.7% of all mutant PAH alleles in Italian hyperphenylalaninemics.

Avaliação do Serviço de Referência em Triagem Neonatal para hipotireoidismo congênito e fenilcetonúria no Estado de Mato Grosso, Brasil / Evaluation of the Neonatal Screening Program for congenital hypothyroidism and phenylketonuria in the State of Mato Grosso, Brazil

OBJETIVO: Avaliar o Serviço de Referência em Triagem Neonatal para hipotireoidismo congênito e fenilcetonúria no Estado de Mato Grosso. MÉTODOS: Estudo transversal, utilizando-se dados secundários dos exames realizados no período de janeiro de 2003 a dezembro de 2004. RESULTADOS: Foram feitos 66.337 testes de triagem com uma cobertura populacional inferior a 70%. A prevalência de fenilcetonúria foi de 1:33.068 nascidos vivos, e de hipotireoidismo congênito foi de 1:9.448 nascidos vivos. Apenas 22% das amostras foram coletadas na idade recomendada; a maioria realizou o teste de triagem entre 8 e 30 dias de vida. A mediana da idade na coleta do teste foi de 12 dias. Verificou-se que o serviço teve dificuldades na reconvocação dos casos suspeitos e dificuldades financeiras na obtenção dos insumos laboratoriais. CONCLUSÕES: A idade na coleta e o atraso na fase de confirmação diagnóstica foram os principais motivos para o atraso do início do tratamento dos casos detectados pelo serviço.

OBJECTIVE: To evaluate the Reference Center for Neonatal Screening for congenital hypothyroidism and phenylketonuria for the State of Mato Grosso. METHOD: Cross-sectional study using secondary data of screening tests carried out from January 2003 to December 2004. RESULTS: 66,337 exams were conducted with population coverage of less than 70%. The prevalence of phenylketonuria was 1:33,068 live births and of congenital hypothyroidism was 1:9,448 live births. Only 22% of the samples were collected at the recommended ag, and most of the samples were collected between the ages of 8 and 30 days. The median age at collection was 12 days. It was observed that the service had difficulties in recalling suspected cases and financial difficulties in obtaining laboratorial reagents. CONCLUSIONS: The age at the time of collection and the delay at the diagnostic confirmation stage were the principal reasons for the delay in the initiation of treatment of the cases detected by the service.

Fenilcetonúria no Brasil: evolução e casos / Phenylketonuria in Brazil: evolution and cases

Os objetivos deste trabalho foram: agrupar informações relevantes à fenilcetonúria, destacando causa, sintomas, tratamento dietético, prevalência nacional e internacional; e identificar a situação do Brasil quanto a essa disfunção metabólica. Foi realizado um levantamento de dados junto ao Ministério da Saúde e aos vários centros de tratamento para fenilcetonúricos no Brasil. Neste estudo foram localizados 1.225 casos de portadores da doença, que recebiam controle e assistência. Um dos principais problemas detectados foi que, na maioria das regiões brasileiras, portadores de fenilcetonúria precisam deslocar-se de seus estados, procurando centros mais capacitados para o tratamento. Nas regiões Norte e Nordeste são poucas as informações disponíveis. Com os resultados obtidos conclui-se que, nem a triagem neonatal, nem os centros de tratamento para fenilcetonúria cobrem todos os casos brasileiros. O Brasil está avançando na organização de dados e ações relativas à fenilcetonúria. Os alimentos específicos são restritos e de alto custo. Novas opções estão sendo pesquisadas, porém, há muito para ser feito, principalmente em pesquisa e produção de alimentos.

Frequencies of phenylalanine hydroxylase mutations I65T, R252W, R261Q, R261X, IVS10nt11, V388M, R408W, Y414C, and IVS12nt1 in Minas Gerais, Brazil

In order to determine the phenylketonuria (PKU) mutation spectrum in the population of Minas Gerais State, Brazil, 78 unrelated PKU patients found by the neonatal screening program from 1993 to 2003 were tested for nine phenylalanine hydroxylase mutations. These mutations were selected due to their high frequencies in other Brazilian populations and in Portugal, where the largest contingent of the Caucasian component of the Brazilian population originated from. The most frequent mutations were V388M (21%), R261Q (16%), IVS10nt11 (13.4%), I65T (5.7%), and R252W (5%). The frequencies of the other four mutations (R261X, R408W, Y414C, and IVS12nt1) did not reach 2%. By testing these nine mutations, we were able to identify 64% of the PKU alleles in our sample. V388M frequency was higher than in any other known population and almost three times larger than that observed in Portugal, probably reflecting genetic drift. The mutation profile, as well as the relative frequency of the different mutations, suggest that the Minas Gerais population more closely resembles that of Portugal than do the other Brazilian populations that have already been tested.

Incidencia de hipotiroidismo congénito y fenilcetonuria en una población de recién nacidos vivos de un hospital perinatológico del Gobierno de la Ciudad de Buenos Aires. Años 2000-2004 / Incidence of congenital hypothyroidism and phenylketonurias in a population of alive newborn of a Perinatal Hospital of the Buenos Aires city. 2000-2004

A partir del primero de diciembre del año 2000 se ha implementado la pesquisa universal del hipotiroidismo congenito y fenilcetonuria en los niños nacidos en el Hospital Materno Infantil "Ramón Sardá". Objetivo: Determinar la incidencia de hipotiroidismo congénito y fenilcetonuria en la población de recién nacidos vivos del Hospital Materno Infantil "Ramón Sardá" durante el período 1 de diciembre de 2000 hasta 1 de diciembre de 2004. Material y métodos: Se procedió a la toma de muestra de sangre del recién nacido de término entre las 48 hs y 72 hs posteriores al nacimiento por punción de talón con la tarjeta de Guthrie. Resultados: Desde el 1 de diciembre del 2000 hasta el 1 de diciembre de 2004 se estudiaron 26.219 recién nacidos detectándose: 13 hipotiroidismos congénitos, y una hiperfenilalaninemia persistente (fenilcetonuria o PKU). También se detectaron tres hiperfenilalaninemias transitorias que requirieron tratamiento durante corto tiempo. Los niños a los cuales se les detectó alguna de estas enfermedades inaparentes al nacer fueron tratados tempranamente en el Hospital de Pediatría "Prof. Dr. Juan P. Garrahan". Conclusión: De esta forma se está dando cumplimiento a la Ley Nº 534 sancionada el 30 del año 2000 del Gobierno de la Ciudad Autónoma de Buenos Aires que establece la obligatoriedad de la pesquisa de estas enfermedades en todos los establecimientos públicos, de la seguridad social y privados en el ámbito de la Ciudad de Buenos Aires.

Incidence of phenylketonuria among mentally retarded children in Kano Nigeria

Phenylketonuria is an inborn error of phenylalanine catabolism causing irreversible mental retardation which can be prevented by dietary therapy. It is characterized by excretion of phenylpyruvic acid in the urine and high concentration of phenylalanine in the blood. Phenylketonuria contributes significantly to the mentally-retarded population. The urine of four [4] of the thirty-two [32] mentally retarded children in a mentally-retarded children home ["Terry Home"] in Kano-city tested positive to phenylpyruvic acid detection test i.e. ferric chloride test. However, high concentration of phenylalanine was detected in three of the four children. These three children, constituting 9.4% f the mentally retarded children, were concluded to suffer from phenylketonuria

Incidência de fenilcetonúria em pacientes com retardamento mental em Alfenas - MG / Incidence of phenylketonuria in patients with mental retardation in Alfenas - Minas Gerais

Foram selecionadas duas instituições para a realização deste trabalho: APAE (Associação de Pais e Amigos dos Excepcionais) e a Clínica Neuropsiquiátrica de Alfenas - MG. Examinaram-se 35 pacientes da APAE, 131 pacientes da Clínica Neuropsiquiátrica, divididos por sexo e faixa etária. A urina foi colhida em dias alternados e analisada no Laboratório de Bioquímica Clínica da EFOA pelas tiras Phenistix e pelo cloreto férrico a 5//. Na APAE, os resultados foram todos negativos e na clínica neuropsiquiátrica, foram encontrados 15 resultados positivos, entre homens e mulheres, havendo um ligeiro aumento no sexo masculino, na faixa etária de 31 a 40 anos, em comparação com o sexo feminino