SARS-CoV-2 pandemic in the Brazilian community of rare diseases: A patient reported survey.

The COVID-19 pandemic has led to a reorganization of health systems to prioritize the fight against the virus. The adoption of social distancing interfered with the flow of existing policies, and may thus negatively affect the most vulnerable groups, such as the rare disease community. Aimming at characterizing the perception of the impact of COVID-19 on the health care of the Brazilian rare disease community, an online questionnaire addressed to patients with rare diseases and their caregivers was disseminated in the Brazilian territory between June 1st to July 5th, 2020. The questions dealt with the sanitary measures adopted; access to medical services; and mental suffering during the pandemic. The survey was answered by 1,466 participants (<18 yo = 53.3%) representing 192 rare diseases. Regarding physical distancing, 1,372 (93.6%) participants did not leave their residence, or did so only when essential; 1,321 (90.1%) always wore masks when leaving home. 1,042 (71.1%) and 995 (67.9%) participants, respectively, referred medical genetics appointments and rehabilitation therapies were postponed/canceled. Telemedicine was experienced by 1,026 (70%), and 68.3% agreed this is a good strategy for health care. Patients with Inborn Errors of Metabolism (IEM, n = 624, 42.5%) appear to have more access to information and ability to overcome difficulties, and feel less threatened, lonely and depressed than the non-IEM group (p < .05). There was an increment of the rare disease patients' vulnerability in the pandemic scenario. The cooperation of patients/caregivers along with adaptation of the health system is crucial and may be so even post-pandemic.

Genotype-phenotype studies in a large cohort of Brazilian patients with Hunter syndrome.

Mucopolysaccharidosis type II (MPS II) is an X-linked inherited disease caused by pathogenic variants in the IDS gene, leading to deficiency of the lysosomal enzyme iduronate-2-sulfatase and consequent widespread storage of glycosaminoglycans, leading to several clinical consequences, with progressive manifestations which most times includes cognitive decline. MPS II has wide allelic and clinical heterogeneity and a complex genotype-phenotype correlation. We evaluated data from 501 Brazilian patients diagnosed with MPS II from 1982 to 2020. We genotyped 280 of these patients (55.9%), which were assigned to 206 different families. Point mutations were present in 70% of our patients, being missense variants the most frequent. We correlated the IDS pathogenic variants identified with the phenotype (neuronophatic or non-neuronopathic). Except for two half-brothers, there was no discordance in the genotype-phenotype correlation among family members, nor among MPS II patients from different families with the same single base-pair substitution variant. Mothers were carriers in 82.0% of the cases. This comprehensive study of the molecular profile of the MPS II cases in Brazil sheds light on the genotype-phenotype correlation and helps the better understanding of the disease and the prediction of its clinical course, enabling the provision of a more refined genetic counseling to the affected families.

Enzyme replacement therapy for Mucopolysaccharidosis Type I among patients followed within the MPS Brazil Network.

Mucopolysaccharidosis type I (MPS I) is a rare lysosomal disorder caused by deficiency of alpha-L-iduronidase. Few clinical trials have assessed the effect of enzyme replacement therapy (ERT) for this condition. We conducted an exploratory, open-label, non-randomized, multicenter cohort study of patients with MPS I. Data were collected from questionnaires completed by attending physicians at the time of diagnosis (T1; n = 34) and at a median time of 2.5 years later (T2; n = 24/34). The 24 patients for whom data were available at T2 were allocated into groups: A, no ERT (9 patients; median age at T1 = 36 months; 6 with severe phenotype); B, on ERT (15 patients; median age at T1 = 33 months; 4 with severe phenotype). For all variables in which there was no between-group difference at baseline, a delta of ≥ ± 20% was considered clinically relevant. The following clinically relevant differences were identified in group B in T2: lower rates of mortality and reported hospitalization for respiratory infection; lower frequency of hepatosplenomegaly; increased reported rates of obstructive sleep apnea syndrome and hearing loss; and stabilization of gibbus deformity. These changes could be due to the effect of ERT or of other therapies which have also been found more frequently in group B. Our findings suggest MPS I patients on ERT also receive a better overall care. ERT may have a positive effect on respiratory morbidity and overall mortality in patients with MPS I. Additional studies focusing on these outcomes and on other therapies should be performed.

Building a National Policy for Rare Disease in Brazil.

Rare diseases (RD) are individually rare, although encompass a significant proportion of the population, affecting not only the individuals but also their families. In Brazil RD is defined by the Ministry of Health as a disorder that affects up to 65 individuals in 100,000, or 1.3 individuals in every 2,000. In this review the environment that led to the publication of a National Policy for Comprehensive Care for People of Rare Disease in 2014, a national plan with the aim to decrease morbidity and mortality of RD, improving the care of people with RD in the public health system are described. The process that finally led to such policy took over a decade, moving forward not only due to technical needs, but having patient organizations as essential actors and advocates. Specialized centers in RD were licensed and, since its publication, 33 centers have been accredited; such process, however, has been slow and concentrated in specific regions and larger cities of the country. Despite the incorporation of genetic tests in 2014 and exome sequencing later in 2020, many genetic tests are not offered by specialized centers, with unequal availability across the country. Public health system in Brazil uses ICD-10 for disease coding, preventing appropriate epidemiologic knowledge of RD in Brazil. Incorporation of new technologies as orphan drugs has been in place and regulation for expedite licensing for new RD drugs were issued, although high cost and availability to RD population has been a challenge.

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.

Identification of a founder effect involving n.197C>T variant in RMRP gene associated to cartilage-hair hypoplasia syndrome in Brazilian patients.

Cartilage-hair hypoplasia syndrome (CHH) is an autosomal recessive disorder frequently linked to n.72A>G (previously known as n.70A>G and n.71A>G), the most common RMRP variant worldwide. More than 130 pathogenic variants in this gene have already been described associated with CHH, and founder alterations were reported in the Finnish and Japanese populations. Our previous study in Brazilian CHH patients showed a high prevalence of n.197C>T variant (former n.195C>T and n.196C>T) when compared to other populations. The aim of this study was to investigate a possible founder effect of the n.197C>T variant in the RMRP gene in a series of CHH Brazilian patients. We have selected four TAG SNPs within chromosome 9 and genotyped the probands and their parents (23 patients previously described and nine novel). A common haplotype to the n.197C>T variant carriers was identified. Patients were also characterized for 46 autosomal Ancestry Informative Markers (AIMs). European ancestry was the most prevalent (58%), followed by African (24%) and Native American (18%). Our results strengthen the hypothesis of a founder effect for the n.197C>T variant in Brazil and indicate that this variant in the RMRP gene originated from a single event on chromosome 9 with a possible European origin.

The 22q11.2 Deletion Syndrome from A Biopsychosocial Perspective: A Series of Cases with an ICF-Based Approach.

The 22q11.2 deletion syndrome (DS) can have a significant impact on functionality. The purpose was to describe 22q11.2DS children with functioning from a biopsychosocial perspective, focusing on the impact of children's health condition from domains of the International Classification of Functioning, Disability, and Health (ICF). METHODS: A descriptive, cross-sectional case series study with seven 22q11.2DS children. A questionnaire with an ICF checklist for 22q11.2DS was completed using a structured interview. The Wechsler Abbreviated Scale of Intelligence (WASI) was used to determine the Intelligence Quotient (IQ). RESULTS: Seven participants from 7 to 12 years old, presented some level of IQ impairment. It was observed that 22q11.2DS children experience significant intellectual, cognitive, and speech impairments across ICF Body Function domains. Impairments related to nose and pharynx were found in only one patient. The most relevant categories considered limitations in the Activity and Participation components pertained to producing nonverbal messages, communication, handling stress, and social interaction. Family, health professionals, and acquaintances were perceived as facilitators in the component Environmental Factors. CONCLUSION: The sample has its functioning affected by aspects that go beyond impairments in body structure and function. The organization of information from the perspective of the ICF is a different approach that helps clinical reasoning.

Neurological Phenotypes of IRF2BPL Gene Variants: A Report of Four Novel Variants.

IRF2BPL gene variants have recently been associated to developmental disability and epilepsy in children and movement disorders in adults. So far, only few cases have been reported; here we present four novel cases identified by exome sequencing, while investigating developmental delay, adult-onset cerebellar ataxia or regression.

Spinal cord compression in young children with type VI mucopolysaccharidosis.

Spinal cord compression (SCC) is a known complication of mucopolysaccharidosis type VI (MPS VI) secondary to atlantoaxial subluxation, craniovertebral stenosis, posterior longitudinal ligament hypertrophy, or dural thickening. SCC is expected to occur in the natural history of the disease, regardless of enzyme replacement therapy (ERT), as intravenous enzyme does not cross the blood-brain barrier. We describe six MPS VI children with SCC, all diagnosed before 7years of age. Within this group, four of the children were diagnosed with SCC after the introduction of ERT. We hypothesize that these patients may illustrate the previously undetected risk of increased joint mobility caused by ERT which may have contributed to increased cervical instability by loosening the neck joint, thus leading to or unmasking SCC. We reinforce the need for close follow-up of SCC, periodic neurological assessment, spine imaging, and neurophysiology in all MPS VI patients before and during ERT. Neurophysiological abnormalities may precede changes in MRI images (as shown in patients 4 and 5 from this sample) and should, therefore, be accessed in MPS VI patient evaluations, allowing for timely intervention and better prognosis. We recognize the limitations of these data due to the small sample size and recommend further investigation into this patient population.