COVID-19 impact on the diagnosis of Inborn Errors of Metabolism: Data from a reference center in Brazil.

The COVID-19 pandemic led to the reorganization of health care in several countries, including Brazil. Inborn Errors of Metabolism (IEM) are a group of rare and difficult to diagnose genetic diseases caused by pathogenic variants in genes that code for enzymes, cofactors, or structural proteins affecting different metabolic pathways. The aim of this study was to evaluate how COVID-19 affected the diagnosis of patients with IEM during the first year of the pandemic in Brazil comparing two distinct periods: from March 1st, 2019 to February 29th, 2020 (TIME A) and from March 1st, 2020 to February 28th, 2021 (TIME B), by the analysis of the number of tests and diagnoses performed in a Reference Center in South of Brazil. In the comparison TIME A with TIME B, we observe a reduction in the total number of tests performed (46%) and in the number of diagnoses (34%). In both periods analyzed, mucopolysaccharidoses (all subtypes combined) was the most frequent LD suspected and/or confirmed. Our data indicates a large reduction in the number of tests requested for the investigation of IEM and consequently a large reduction in the number of diagnoses caused by the COVID-19 pandemic leading to a significant underdiagnosis of IEM.

Updated birth prevalence and relative frequency of mucopolysaccharidoses across Brazilian regions.

The mucopolysaccharidoses (MPS) are a group of lysosomal storage disorders caused by 11 enzyme deficiencies, classified into seven types. Data on the birth prevalence of each MPS type are available for only a few countries, and the totality of cases may be underestimated. To determine the epidemiological profile of MPS in each Brazilian region, we analyzed data collected between 1982 and 2019 by a national reference laboratory and identified 1,652 patients. Using data between 1994 and 2018, the birth prevalence (by 100,000 live births) for MPS was 1.57. MPS II was the most common type of MPS in Brazil, and its birth prevalence was 0.48 (0.94 considering only male births). Regarding the number of cases per region, MPS II was the most frequent in the North and Center-West (followed by MPS VI), and also in the Southeast (followed by MPS I); MPS I and MPS II were the most common types in the South; and MPS VI was the most common in the Northeast (followed by MPS II). The differences observed in the relative frequencies of MPS types across Brazilian regions are likely linked to founder effect, endogamy, and consanguinity, but other factors may be present and need further investigation.

Newborn screening for lysosomal disorders in Brazil: A pilot study using customized fluorimetric assays.

Lysosomal storage disorders (LSDs) are a group of genetic disorders characterized by deficiency of specific lysosomal enzymes. In general, patients are clinically normal at birth, and progressively develop severe signs and symptoms. Diagnosis is usually made several years after onset of manifestations, preventing patients to have the benefits of the early treatment. Newborn screening programs are being considered for LSDs to allow early diagnosis and treatment. The present study evaluated the feasibility of a customized screening approach based on modified fluorometric assays with reduced amounts of reagents, substrates and samples for: mucopolysaccharidosis (MPS) type I (MPS I), MPS VI, Fabry, Gaucher, and Pompe diseases. We also evaluated the advantages of including blood chitotriosidase and urinary glycosaminoglycans in the protocol. By the measurement of the specific disease-associated enzymes (plus blood chitotriosidase and urinary glycosaminoglycans) we analyzed 834 de-identified DBS of unselected newborns. No positive case was detected, and the false-positive rates were low. Taking into consideration the limitations of this methodology, we believe that, after defining proper cutoffs, it could be a viable alternative to provide NBS for LSDs by laboratories that may not be able to afford the commercial methods available.

Population medical genetics: translating science to the community.

Rare genetic disorders are currently in the spotlight due to the elevated number of different conditions and significant total number of affected patients. The study of these disorders is extremely helpful for the elucidation of physiological processes related with complex disorders. Isolated populations are instrumental for the study of genetic disorders, considering their homogeneity and high proportion of affected patients in a small geographic area. These favorable conditions lead to the creation of a new discipline, known as "population medical genetics", which integrates medical genetics, population genetics, epidemiological genetics and community genetics. In order to develop practical activities in this new discipline, the National Institute of Population Medical Genetics (INaGeMP) was created in 2008 in Brazil. INaGeMP has developed several tools and funded numerous research activities. In this review, we highlight three successful projects developed in the first 10 years of INaGeMP activities (2008-2018): a newborn screening pilot study for MPS VI in Northeast Brazil, the study of Machado-Joseph disease in Brazilian families with Azorian ancestry, and the high twinning rate in a small town in southern Brazil. The results of these projects in terms of scientific output and contributions to the affected communities highlight the success and importance of INaGeMP.

Investigation of newborns with abnormal results in a newborn screening program for four lysosomal storage diseases in Brazil.

Lysosomal storage diseases (LSDs) are genetic disorders, clinically heterogeneous, mainly caused by defects in genes encoding lysosomal enzymes that degrade macromolecules. Several LSDs already have specific therapies that may improve clinical outcomes, especially if introduced early in life. With this aim, screening methods have been established and newborn screening (NBS) for some LSDs has been developed. Such programs should include additional procedures for the confirmation (or not) of the cases that had an abnormal result in the initial screening. We present here the methods and results of the additional investigation performed in four babies with positive initial screening results in a program of NBS for LSDs performed by a private laboratory in over 10,000 newborns in Brazil. The suspicion in these cases was of Mucopolysaccharidosis I - MPS I (in two babies), Pompe disease and Gaucher disease (one baby each). One case of pseudodeficiency for MPS I, 1 carrier for MPS I, 1 case of pseudodeficiency for Pompe disease and 1 carrier for Gaucher disease were identified. This report illustrates the challenges that may be encountered by NBS programs for LSDs, and the need of a comprehensive protocol for the rapid and precise investigation of the babies who have an abnormal screening result.

Elevation of glycosaminoglycans in the amniotic fluid of a fetus with mucopolysaccharidosis VII.

OBJECTIVE: The aim of this study was to quantify glycosaminoglycans (GAGs) in amniotic fluid (AF) from an MPS VII fetus compared with age-matched fetuses obtained from normal pregnancies. METHOD: Disaccharides were measured by liquid chromatography tandem mass spectrometry, compared to age-matched controls. Enzyme assay was performed in AF supernatant or cultured amniocytes. GUSB was analyzed by next generation sequencing using Ion Torrent Personal Genome Machine with a customized panel. RESULTS: No activity of ß-glucuronidase was detected in fetal cells. The pregnancy was spontaneously terminated in the third trimester. Genetic studies identified a homozygous mutation of p.N379D (c.1135A > G) in the GUSB gene. Liquid chromatography tandem mass spectrometry showed that chondroitin sulfate, dermatan sulfate, heparan sulfate, and keratan sulfate levels were markedly increased in the MPS VII AF, compared to those in age-matched control AF (dermatan sulfate, heparan sulfate, and chondroitin-6-sulfate more than 10 × than age-matched controls; chondroitin-4-sulfate and keratan sulfate more than 3 times higher). CONCLUSION: This is the first report of specific GAG analysis in AF from an MPS VII fetus, indicating that GAG elevation in AF occurs by 21 weeks of gestation and could be an additional tool for prenatal diagnosis of MPS VII and potentially other MPS types. © 2017 John Wiley & Sons, Ltd.

Valores de referencia de β-glucosidasa y quitotriosidasa en gotas de sangre seca de lactantes venezolanos / Reference Values for β-glucosidase and chitotriosidase using dried blood spots in Venezuelan infants

La enfermedad de Gaucher es un trastorno de herencia autosómica recesiva y la enfermedad de depósito lisosomal más frecuente causada por deficiencia de la actividad enzimática de la β-Glucosidasa. Objetivo: establecer valores de referencia de actividad enzimática lisosomal de β-glucosidasa y quitotriosidasa en lactantes en población Venezolana. Método: Se realizó un estudio prospectivo y transversal en 98 lactantes sanos con edades comprendidas entre 1 mes y 24 meses, de ambos sexos (48 femeninos y 50 masculinos). La actividad enzimática de β-glucosidasa y quitotriosidasa fue determinada en gotas de sangre seca (siglas en inglés, DBS) siguiendo el protocolo propuesto por Chamoles y col. El análisis estadístico de los datos se realizó con el programa estadístico SPSS Statistics 17.0 para Windows. Resultados: El rango de actividad enzimática para la β-Glucosidasa obtenido en esta investigación fue 2,3 - 12 nmol/ml/h, con una media de 6,7 ± 2,5 y para la Quitotriosidasa 0 - 44,2 nmol/ml/h con una media de 18,4 ± 10,4 nmol/ml/h, utilizando discos de papel de filtro de 3mm de diámetro con sangre seca (aproximadamente 3,6 μl de sangre). Conclusión: Los valores de referencia de actividad enzimática lisosomal en DBS para β-glucosidasa y quitotriosidasa son establecidos por vez primera en lactantes sanos venezolanos; no obstante, estos resultados difieren con los reportados en estudios internacionales, recomendándose la determinación de valores de referencias autóctonos en diferentes grupos etarios.

Gaucher´s Disease is an autosomal recessive disorder and the most common lysosomal storage disease caused by deficiency of β-glucosidase enzyme activity. Objetive: to establish reference values for lysosomal enzyme activity of β-glucosidase and chitotriosidase in Venezuelan infants. Methods:A prospective cross-sectional study was conducted in 98 healthy infants with ages ranging from 1 month to 24 months (48 females and 50 males). Enzymatic activity of β-glucosidase and chitotriosidase were determined in dried blood spots (DBS) following the protocol by Chamoles et al. Statistical analysis of data was performed with software SPSS 17.0 for Windows Statistics. Results: The range of enzymatic activity for β-glucosidase was 2.3 to 12 nmol/ml/h, with an average of 6.7 ± 2.5. Chitotriosidase activity was from 0 to 44.2 nmol/ml/h with an average of 18.4 ± 10.4 using 3mm diameter discs of filter paper with dried blood (approximately 3.6 μl of blood). Conclusions: The reference values of lysosomal enzyme activity in DBS for β-Glucosidase and quitotriosidase were established for the first time in healthy Venezuelan infants; however, these results differ from those reported in international studies, for which reason autochthonous reference values should be determined in different age groups.

Screening for Attenuated Forms of Mucopolysaccharidoses in Patients with Osteoarticular Problems of Unknown Etiology.

INTRODUCTION: The mucopolysaccharidoses (MPS) are a group of 11 inborn errors of metabolism (IEM) which are part of the lysosomal storage diseases (LSDs). The MPS are multisystemic conditions that affect the entire body, with variations in the clinical presentation, having specific treatments available depending on the type of MPS. Nearly all MPS disorders compromise the osteoarticular system in different ways, and virtually all patients have abnormal urinary excretion of glycosaminoglycans (GAGs). MPS are rare diseases that are underdiagnosed due to health-care professionals' lack of awareness, to poor access to screening and diagnostic methods, and to their extensive clinical heterogeneity. Attenuated forms may occur, which can make diagnosis of MPS even more difficult. METHODS: This study was conducted prospectively from March 2012 to January 2014 and included 55 patients at rheumatology and/or orthopedic services in Porto Alegre, Brazil. The screened patients presented with articular manifestations with no defined etiology. These patients were screened by quantitative and qualitative assessment of urinary GAGs. RESULTS AND DISCUSSION: Among the 55 cases investigated, one 15-year-old patient exhibited increased urinary GAG excretion; this patient was subsequently diagnosed with an attenuated form of MPS II, which was previously undetected. CONCLUSION: Although the proportion of patients with MPS identified in the study sample was small (1/55), this study shows that these diseases are underdiagnosed and that systematic screening can help identify patients who may benefit from specific treatments already available for several MPS types.

Reflexões de uma experiência de oficina terapêutica infantil no CAPSIA: os Sonhadores / A workshop experience therapy with child at CAPSIA: the Dreamers

Este trabalho busca apresentar contribuições a partir das reflexões oriundas da experiência interdisciplinar que integrou o estágio do Curso de Psicologia e o projeto de extensão PET - Saúde1 da área da Fisioterapia da Universidade de Santa Cruz do Sul, no Centro de Atenção Psicossocial da Infância e Adolescência de Santa Cruz do Sul. Este local atende crianças e adolescentes em situações de transtornos e sofrimentos psíquicos. O presente trabalho tem como objetivo apresentar, a partir de um caso, os resultados possíveis através do uso dos sonhos segundo a visão da Teoria Analítica Junguiana como um instrumento para o trabalho em oficinas. Neste sentido, o método se revelou muito positivo, pois percebemos grandes avanços no paciente, já que demonstrou melhoras tanto nas suas relações sociais como também pessoais. Desta forma, o trabalho com os sonhos se mostra como ferramenta riquíssima para intervenção terapêutica no processo de oficina, já que auxilia na busca de saúde psicossocial.

The objective of this paper is to present reflections of interdisciplinary experience that integrated the stage psychology course of UNISC and the extension project PET - Saúde of physiotherapy area on a CAPSIA (Psychosocial Care Center for Children and Adolescents) of Santa Cruz do Sul. It is a health center that serves children and adolescents in situations of disorders and mental suffering. We use dreams, based on Jungian theory, as an intervention method. Here we present a case to demonstrate the positive results of using this method, as we see great advances in the patient, both showing improvements in their social relationships as well as personal. Working with dreams proved to be a very rich tool for therapeutic intervention aiding the child in their psychosocial health-seeking process.

Oxidative stress and inflammation in mucopolysaccharidosis type IVA patients treated with enzyme replacement therapy.

Mucopolysaccharidosis type IVA (MPS IVA) is an inborn error of glycosaminoglycan (GAG) catabolism due to the deficient activity of N-acetylgalactosamine-6-sulfate sulfatase that leads to accumulation of the keratan sulfate and chondroitin 6-sulfate in body fluids and in lysosomes. The pathophysiology of this lysosomal storage disorder is not completely understood. The aim of this study was to investigate oxidative stress parameters, pro-inflammatory cytokine and GAG levels in MPS IVA patients. We analyzed urine and blood samples from patients under ERT (n=17) and healthy age-matched controls (n=10-15). Patients presented a reduction of antioxidant defense levels, assessed by a decrease in glutathione content and by an increase in superoxide dismutase activity in erythrocytes. Concerning lipid and protein damage, it was verified increased urine isoprostanes and di-tyrosine levels and decreased plasma sulfhydryl groups in MPS IVA patients compared to controls. MPS IVA patients showed higher DNA damage than control group and this damage had an oxidative origin in both pyrimidine and purine bases. Interleukin 6 was increased in patients and presented an inverse correlation with GSH levels, showing a possible link between inflammation and oxidative stress in MPS IVA disease. The data presented suggest that pro-inflammatory and pro-oxidant states occur in MPS IVA patients even under ERT. Taking these results into account, supplementation of antioxidants in combination with ERT can be a tentative therapeutic approach with the purpose of improving the patient's quality of life. To the best of our knowledge, this is the first study relating MPS IVA patients with oxidative stress.

Enzyme Replacement Therapy With Elosulfase Alfa Decreases Storage of Glycosaminoglycan in White Blood Cells of Patients With Morquio A Syndrome

Abstract Mucopolysaccharidosis IVA (MPS IVA; Morquio A syndrome) is a lysosomal storage disorder caused by a deficient N-acetylgalactosamine-6-sulfate sulfatase activity, leading to cellular storage of undegraded keratan sulfate. Recently enzyme replacement therapy (ERT) was approved for MPS IVA, but some of ERT effects are still unknown. In the present study, we aimed to evaluate the efficacy of elosulfase alfa upon glycosaminoglycan (GAG) storage in peripheral blood white blood cells of patients with MPS IVA treated for 6 months, comparing samples from patients who received weekly infusions of enzyme (ERT-W) versus infusions every other week (ERT-EOW) versus placebo. A significant reduction in GAG storage was observed in both ERT-treated groups, with weekly ERT showing slightly better performance than ERT-EOW.

A community-based study of mucopolysaccharidosis type VI in Brazil: the influence of founder effect, endogamy and consanguinity.

Mucopolysaccharidosis type VI (MPS VI - Maroteaux-Lamy syndrome) is a globally rare lysosomal storage disease caused by a deficiency of arylsulfatase B. However, in Monte Santo, a poor and isolated rural region in Northeast Brazil with large family sizes and high rates of community endogamy and parental consanguinity (α = 0.00483), 9 living and 4 now deceased individuals in 11 kindreds have been diagnosed with MPS VI, all with the same p.H178L missense founder mutation. A further 33 deceased persons have been identified by family members as exhibiting the disease phenotype. Detailed pedigrees were constructed for the 13 genomically confirmed MPS VI patients, with blood samples collected from 236 unaffected family members to determine the prevalence of the p.H178L mutation. A total of 98 (20.8%) mutant alleles and 374 (79.2%) normal alleles were identified, with 41.5% of the individuals heterozygous for the p.H178L mutation and 58.5% homozygous for the normal allele. A significant number of other family members with a 50 or 25% chance of being heterozygous for the p.H178L mutation were unavailable for testing. The data indicate a compelling case for community-based neonatal screening in conjunction with further initiatives among MPS VI family members to promote genetic education and genetic counselling.

Genetic studies in a cluster of mucopolysaccharidosis type VI patients in Northeast Brazil.

Mucopolysaccharidosis type VI (MPS VI, Maroteaux-Lamy syndrome) is a lysosomal storage disease caused by deficiency of arylsulphatase B. The incidence of MPS VI is very low, usually less than 1 case for every 1,000,000 newborns. In Northeast Brazil we identified in the county of Monte Santo (52,360 inhabitants) thirteen patients with MPS VI. The aim of this work was to identify the mutation(s) present in these patients and analyze intragenic SNPs to define possible haplotypes. The 13 MPS VI patients were found to be homozygous for the p.H178L mutation. All patients have the same haplotype for the intragenic SNPs. Based on current data, the prevalence of MPS VI in this region is estimated as 1:5,000 newborns. These results, together with pedigree analysis, strongly suggest a founder effect accounting for the high frequency of p.H178L mutation in this area. This reinforces the need of a comprehensive community genetics program for this area.