Information and Diagnosis Networks - tools to improve diagnosis and treatment for patients with rare genetic diseases

Hematopoietic stem cell transplantation in inborn errors of metabolism-a retrospective analysis on behalf of the pediatric disease working party from the Brazilian Society of Bone Marrow Transplantation and Cellular Therapy

Hematopoietic stem cell transplantation (HSCT) is an established treatment for selected patients with inborn errors of metabolism. In this first report from the PDWP-SBTMO, we included 105 patients transplanted between 1988 and 2021 across six Brazilian HSCT centers. The most prevalent diseases were X-linked adrenoleukodystrophy (n = 61) and mucopolysaccharidosis (type I n = 20; type II n = 10), with a median age at HSCT of 8.7 years and 2.1 years, respectively. Most conditioning regimens were myeloablative and busulfan-based. With a median follow-up of 6.7 years, the 5-years overall survival (OS) was 75% (95% CI, 0.65-0.82) with a superior 5-years OS for those transplanted after 2010 (87% vs. 63%, p = 0.01). Higher risk of death was associated with the use of haploidentical donor (HR8.86, p 0.021), unrelated cord blood (HR 8.76, p 0.005), unrelated donor (HR 5.91, p 0.02), and for HSCT performed before 2010 (HR 4.16, p = 0.0015). The CI of acute GVHD was 24.8%, while chronic GVHD was 9.5%. Major causes of death were infections (n = 8), GVHD (n = 6), and neurologic progression (n = 3). Despite improvements in transplant outcomes since 2011, challenges persist, emphasizing the need for early diagnosis, timely transplantation and expanding HSCT centers with expertise in the field.

Medical Genetics in Brazil in the 21st Century: A Thriving Specialty and Its Incorporation in Public Health Policies

Brazil is a continent-size country with 203 million inhabitants, classified as a developing upper-middle-income country, although inequities remain significant. Most of the population is assisted by the public Unified Health System (SUS), along with a thriving private health sector. Congenital malformations are the second leading cause of infant mortality and chronic/genetic disorders and a significant burden in hospital admissions. The past two decades have been crucial for formalizing medical genetics as a recognized medical specialty in the SUS, as well as for implementing a new health policy by the Ministry of Health for comprehensive care for rare diseases. These public health policies had the broad support of the Brazilian Society of Medical Genetics and Genomics and patient organizations. Most comprehensive genetic services are concentrated in large urban centers in the South and Southeast regions of Brazil; with this new policy, new services throughout the country are progressively being integrated. The number of medical geneticists increased by 103% in a decade. Details on the policy and an overview of the availability of services, testing, human resources, newborn screening, research projects, patient organizations, and relevant issues regarding medical genetics in this vast and diverse country are presented.

Training of community health agents - a strategy for earlier recognition of mucopolysaccharidoses

Primary Health Care (PHC) is the gateway for patients in the Brazilian unified health system (Sistema Único de Saúde-SUS), playing an extremely important role in the identification of potential patients with genetic diseases, and referral to specialized and tertiary health services. The PHC is composed of a multidisciplinary team, including the Community Health Agent, who is in direct contact with the community. To implement an educational program aimed at community health agents working in several municipalities in the state of Rio Grande do Sul (RS), Brazil. The training was focused on genetic diseases in general, with a special focus on identifying patients with Mucopolysaccharidosis (MPS). Tests were applied before and after the educational intervention, in order to assess the participants' knowledge on the topic at these two moments. The study covered a total of ten training sessions carried out in eight municipalities in the RS state, training 374 community health agents. The number of correct answers in the pre-test (n = 339) was 8,4 (SD 1.2), while in the post-test (n = 361) it was 9,2 (SD 0.8). Statistical analysis showed that the educational intervention effectively provided information about genetic diseases to the participants. Considering that community health agents are of fundamental importance in the identification and prevention of diseases and in the better navigation of the patients on the SUS, these professionals play a key role in the field of rare genetic diseases, and continuous training strategies should be taken.

Availability of Genetic Tests in Public Health Services in Brazil: Data from the Brazilian Rare Diseases Network

INTRODUCTION

The Brazilian Policy for Comprehensive Care for People with Rare Diseases (BPCCPRD) was published in 2014, accrediting several reference centers and incorporating many genetic tests for the diagnosis of rare diseases (RDs). The Brazilian Network of Rare Diseases (RARAS) comprises more than 40 institutions that offer diagnosis and treatment for RDs in Brazil. This network includes Reference Services for Rare Diseases (RDRS), Reference Services for Newborn Screening (NSRS), and University Hospitals distributed in all Brazilian regions.

OBJECTIVE

The aim of the study was to map the availability and distribution of the BPCCPRD diagnostic procedures in the Brazilian Unified Health System through RARAS.

METHOD

Data were collected through a questionnaire on the Research Electronic Data Capture platform, with 22 questions regarding the availability of procedures. Thirty-seven coordinators from RARAS participating centers received the questionnaire link for participation by email from August/2020 to March/2021. All participating institutions ethically approved this project.

RESULTS

Of the 37 institutions, 23 (62.16%) offered cytogenetic tests, 20 (54.05%) offered molecular procedures, and 22 (59.46%) offered inborn errors of metabolism diagnostic tests. The Southern blot analysis, enzyme assays on cultured tissue and urinary organic acid tests had the highest outsourcing rate. On the other hand, the procedures most frequently performed on-site were bone marrow karyotype and long-term cultured karyotype. It was observed that 10 of the 37 centers (27%) did not provide access to investigated procedures (on-site or outsourced). The North and Midwest regions stood out in terms of the unavailability of such techniques in at least 40% of the evaluated institutions.

DISCUSSION AND CONCLUSION

This study reveals large discrepancies in the supply of diagnostic procedures in the Brazilian territory. Moreover, there is a broad collaboration between services through the outsourcing of multiple diagnostic techniques to address this issue. Finally, this work corroborates the importance of mapping services for the diagnosis and treatment of individuals with RDs to propose actions for the better supply and distribution of these procedures.

Enhancing Equitable Access to Rare Disease Diagnosis and Treatment around the World: A Review of Evidence, Policies, and Challenges

This document provides a comprehensive summary of evidence on the current situation of rare diseases (RDs) globally and regionally, including conditions, practices, policies, and regulations, as well as the challenges and barriers faced by RD patients, their families, and caregivers. The document builds on a review of academic literature and policies and a process of validation and feedback by a group of seven experts from across the globe. Panelists were selected based on their academic merit, expertise, and knowledge regarding the RD environment. The document is divided into five main sections: (1) methodology and objective; (2) background and context; (3) overview of the current situation and key challenges related to RDs covering six dimensions: burden of disease, patient journey, social impact, disease management, RD-related policies, and research and development; (4) recommendations; and (5) conclusions. The recommendations are derived from the discussion undertaken by the experts on the findings of this review and provide a set of actionable solutions to the challenges and barriers to improving access to RD diagnosis and treatment around the world. The recommendations can support critical decision-making, guiding efforts by a broad range of RDs stakeholders, including governments, international organizations, manufacturers, researchers, and patient advocacy groups.

Challenges and recommendations to increasing the use of exome sequencing and whole genome sequencing for diagnosing rare diseases in Brazil: an expert perspective

Early diagnosis of genetic rare diseases is an unmet need in Brazil, where an estimated 10-13 million people live with these conditions. Increased use of chromosome microarray assays, exome sequencing, and whole genome sequencing as first-tier testing techniques in suitable indications can shorten the diagnostic odyssey, eliminate unnecessary tests, procedures, and treatments, and lower healthcare expenditures. A selected panel of Brazilian experts in fields related to rare diseases was provided with a series of relevant questions to address before a multi-day conference. Within this conference, each narrative was discussed and edited through numerous rounds of discussion until agreement was achieved. The widespread adoption of exome sequencing and whole genome sequencing in Brazil is limited by various factors: cost and lack of funding, reimbursement, awareness and education, specialist shortages, and policy issues. To reduce the burden of rare diseases and increase early diagnosis, the Brazilian healthcare authorities/government must address the barriers to equitable access to early diagnostic methods for these conditions. Recommendations are provided, including broadening approved testing indications, increasing awareness and education efforts, increasing specialist training opportunities, and ensuring sufficient funding for genetic testing.

Fifteen years of enzyme replacement therapy for mucopolysaccharidosis type VI (Maroteaux-Lamy syndrome): a case report

Background

Mucopolysaccharidosis VI, or Maroteaux–Lamy disease, is an autosomal recessive disease characterized by deficiency of the enzyme arylsulfatase B in the lysosomal catabolism of glycosaminoglycans. Due to reduced (or even null) enzyme activity, glycosaminoglycans (mainly dermatan sulfate) accumulates, leading to a multisystemic disease. Mucopolysaccharidosis VI induces reduced growth, coarse face, audiovisual deficits, osteoarticular deformities, and cardiorespiratory issues, hampering the quality of life of the patient. Enzyme replacement therapy with galsulfase (Naglazyme, BioMarin Pharmaceuticals Inc., USA) is the specific treatment for this condition. Although studies have shown that enzyme replacement therapy slows the progression of the disease, the effects of long-term enzyme replacement therapy remain poorly understood.

Case presentation

A 29-year-old, Caucasian, male patient diagnosed with mucopolysaccharidosis VI was treated with enzyme replacement therapy for over 15 years. Enzyme replacement therapy was initiated when patient was 13 years old. The patient evolved multiplex dysostosis, carpal tunnel syndrome, thickened mitral valve, and hearing and visual loss.

Conclusions

Although enzyme replacement therapy did not prevent the main signs of mucopolysaccharidosis VI, it slowed their progression. Additionally, enzyme replacement therapy was associated with a longer survival compared with the untreated affected sibling. Taken together, the results indicate that enzyme replacement therapy positively modified the course of the disease.

Rare disease patients’ needs: an up-to-date analysis and future directions

The interest to rare diseases has increased in the recent decades. Legislation seeks to facilitate patients’ access to innovative and effective treatment and to define incentives for pharmaceutical and biotechnology companies to develop new medicines for rare diseases.The current review presents the current knowledge and adopted solutions in the field of rare diseases and discusses the future issues and unmet needs that should be resolved for affected patients and their families. Along with the positive trends in the field of rare diseases, there are still issues related to diagnosis and inequal care for some patients groups that should be solved over the next decade. The innovative digital health methods, which have been improved continuously in the recent years, implementation of improved versions of patient-centered policy plans and programs and investment in advanced therapies could move forward the rare diseases to new horizons giving them the opportunity to overcome the main barriers and challenges in the whole journey of the patients – from diagnosis through treatment to follow-up.

Clinical trials for genetic diseases in Latin America

Latin American geneticists have been contributing to the scientific development of Human and Medical Genetics fields since the early 1950s. In the last decades, as Medical Genetics is moving toward a new era of innovative therapies for previously untreatable conditions, the participation of Latin America in clinical trials is also increasing. This review discusses the particularities regarding funding, regulatory, and ethical aspects of conducting clinical trials for genetic diseases in Latin America, with an especial focus on Brazil, the largest country with the highest number of studies. Although there are still several barriers to overcome, the recent development of orphan drug legislation and policies for rare diseases in many Latin American countries indicates a growing opportunity for the participation of the region in international efforts for the development of new therapies for genetic diseases.

Mucopolysaccharidosis VII in Brazil: natural history and clinical findings

Background

Mucopolysaccharidosis type VII (MPS VII), also known as Sly syndrome, caused by deficiency of the lysosomal enzyme β-glucuronidase, is an ultra-rare disorder with scarce epidemiological data and few publications about natural history and clinical spectrum.

Methods

We conducted a case series report which included retrospective data from all MPS VII patients diagnosed through the “MPS Brazil Network” who were known to be alive in 2020 in Brazil (N = 13). Clinical data were obtained from a review of the medical records and descriptive statistics and variables were summarized using counts and percentages of the total population.

Results

The majority of the patients were from the Northeast region of Brazil. Among the signs and symptoms that raised the clinical suspicion of MPS, coarse face was the most frequent; 58% of the patients had a history of non-immune hydrops fetalis. All the subjects presented short neck and trunk. The majority presented typical phenotypical signs of MPS disorders. They all presented neurodevelopmental delay and cognitive impairment. About half of this cohort had knees deformities. Dysostosis multiplex was identified in almost all patients and cardiomyopathy was less frequent than observed in other types of MPSs. The mean age at diagnosis was 5 years, ranging from 1 to 14 years. Almost all patients (12/13) were homozygous for the c.526C>T (p.Leu176Phe) mutation. A novel variant of the GUSB gene was found, the c.875T>C (p.Leu292Pro), in a compound heterozygous with the c.526C>T (p.Leu176Phe) variant.

Conclusions

This case series is the biggest data collection of MPS VII patients alive in Latin America. The overall clinical picture of the MPS VII patients is very similar to other MPS disorders, including a spectrum of severity and delayed diagnosis.

Implementation of chromosomal microarrays in a cohort of patients with intellectual disability at the Argentinean public health system

Intellectual disability is a neurodevelopmental disorder in which genetic, epigenetic and environmental factors are involved. In consequence, the determination of its etiology is usually complex. Though many countries have migrated from conventional cytogenetic analysis to chromosomal microarrays as the first-tier genetic test for patients with this condition, this last technique was implemented in our country a few years ago. We report on the results of the implementation of chromosomal microarrays in a cohort of 133 patients with intellectual disability and dysmorphic features, normal karyotype and normal subtelomeric MLPA results in an Argentinean public health institution. Clinically relevant copy number variants were found in 12% of the patients and one or more copy number variants classified as variants of uncertain significance were found in 5.3% of them. Although the diagnostic yield of chromosomal microarrays is greater than conventional cytogenetics for these patients, there are financial limitations to adopt this technique as a first-tier test in our country, especially in the public health system.