Orphan or Rare Diseases

Genetic newborn screening and digital technologies: A project protocol based on a dual approach to shorten the rare diseases diagnostic path in Europe

Wed, 2023-11-22 06:00

PLoS One. 2023 Nov 22;18(11):e0293503. doi: 10.1371/journal.pone.0293503. eCollection 2023.

ABSTRACT

Since 72% of rare diseases are genetic in origin and mostly paediatrics, genetic newborn screening represents a diagnostic "window of opportunity". Therefore, many gNBS initiatives started in different European countries. Screen4Care is a research project, which resulted of a joint effort between the European Union Commission and the European Federation of Pharmaceutical Industries and Associations. It focuses on genetic newborn screening and artificial intelligence-based tools which will be applied to a large European population of about 25.000 infants. The neonatal screening strategy will be based on targeted sequencing, while whole genome sequencing will be offered to all enrolled infants who may show early symptoms but have resulted negative at the targeted sequencing-based newborn screening. We will leverage artificial intelligence-based algorithms to identify patients using Electronic Health Records (EHR) and to build a repository "symptom checkers" for patients and healthcare providers. S4C will design an equitable, ethical, and sustainable framework for genetic newborn screening and new digital tools, corroborated by a large workout where legal, ethical, and social complexities will be addressed with the intent of making the framework highly and flexibly translatable into the diverse European health systems.

PMID:37992053 | PMC:PMC10664952 | DOI:10.1371/journal.pone.0293503

Categories: Literature Watch

Liver Transplantation for Mahvash Disease, an Inborn Error of Metabolism

Wed, 2023-11-22 06:00

N Engl J Med. 2023 Nov 23;389(21):2010-2013. doi: 10.1056/NEJMe2310332.

NO ABSTRACT

PMID:37991861 | DOI:10.1056/NEJMe2310332

Categories: Literature Watch

Cell lineage analysis with somatic mutations reveals late divergence of neuronal cell types and cortical areas in human cerebral cortex

Tue, 2023-11-21 06:00

bioRxiv. 2023 Nov 6:2023.11.06.565899. doi: 10.1101/2023.11.06.565899. Preprint.

ABSTRACT

The mammalian cerebral cortex shows functional specialization into regions with distinct neuronal compositions, most strikingly in the human brain, but little is known in about how cellular lineages shape cortical regional variation and neuronal cell types during development. Here, we use somatic single nucleotide variants (sSNVs) to map lineages of neuronal sub-types and cortical regions. Early-occurring sSNVs rarely respect Brodmann area (BA) borders, while late-occurring sSNVs mark neuron-generating clones with modest regional restriction, though descendants often dispersed into neighboring BAs. Nevertheless, in visual cortex, BA17 contains 30-70% more sSNVs compared to the neighboring BA18, with clones across the BA17/18 border distributed asymmetrically and thus displaying different cortex-wide dispersion patterns. Moreover, we find that excitatory neuron-generating clones with modest regional restriction consistently share low-mosaic sSNVs with some inhibitory neurons, suggesting significant co-generation of excitatory and some inhibitory neurons in the dorsal cortex. Our analysis reveals human-specific cortical cell lineage patterns, with both regional inhomogeneities in progenitor proliferation and late divergence of excitatory/inhibitory lineages.

PMID:37986891 | PMC:PMC10659282 | DOI:10.1101/2023.11.06.565899

Categories: Literature Watch

Role of pharmacists in the context of rare diseases: a scoping review protocol

Tue, 2023-11-21 06:00

BMJ Open. 2023 Nov 21;13(11):e072001. doi: 10.1136/bmjopen-2023-072001.

ABSTRACT

INTRODUCTION: Rare diseases are chronic conditions, generally incurable, progressive and disabling, which may result in early death. Access to therapeutic products, both medicines and appropriate medical devices, is essential to prevent the progression of the disease and maintain the patients' quality of life. Pharmacists can be part of health teams, in charge of guiding patients' journey, monitoring pharmacotherapy and identifying risks. This scoping review aims to identify and summarise evidence on the role of pharmacists and its impact in the field of rare diseases.

METHODS AND ANALYSIS: The searches will be conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guideline for protocols. Three electronic databases will be consulted. Studies reporting on qualitative and/or quantitative data from any world region will be considered. There will be no language or initial time limit for studies inclusion, until December 2022. To be eligible for inclusion, studies must focus on the role pharmacists in clinical services aimed at promote the access to medicines, prevention and resolution of problems related to pharmacotherapy. No assessments of items' quality will be made, as the purpose of this scoping review is to synthesise and describe the coverage of the evidence. Clinical, humanistic or economic outcomes from studies that meet the inclusion criteria will be included in the review. The analysis will synthesise the available evidence and may be able to push pharmaceutical practice forward, aiding professionals, educators and managers in the implementation of new approaches to better meet the needs of rare diseases and providing opportunities for future research.

ETHICS AND DISSEMINATION: Primary data will not be collected in this study and formal ethical approval is not required. The findings of this study will be disseminated through peer-reviewed publications and conference presentations.

PMID:37989368 | PMC:PMC10668274 | DOI:10.1136/bmjopen-2023-072001

Categories: Literature Watch

Development and content validation of a sunlight exposure diary in patients with erythropoietic protoporphyria

Mon, 2023-11-20 06:00

J Patient Rep Outcomes. 2023 Nov 20;7(1):119. doi: 10.1186/s41687-023-00655-y.

ABSTRACT

BACKGROUND: Erythropoietic protoporphyria is a rare, inherited disorder presenting in early childhood with severe, painful phototoxicity. EPP has significant impacts on health-related quality of life, though there is variable disease severity. Accurately capturing how much time individuals with EPP can spend outdoors before they develop symptoms is critical to understanding HRQoL and measuring therapeutic response. Therefore, the goal of this study was to develop a comprehensive and content valid sun exposure diary to assess the efficacy of new therapies in individuals with EPP.

METHODS: Qualitative interviews were conducted with adult and adolescent EPP participants, as well as five clinical experts, to obtain their input on the content of an existing sun exposure diary. Revisions to the diary were made based on evidence generated in cognitive debriefing interviews analyzed in eight consecutive groups of EPP participant.

RESULTS: Interviews were conducted with 17 adults and 6 adolescents with EPP. The average age of adults was 40 years and of adolescents was 14 years. Clinical experts thought the original diary needed clarification on the description of symptoms, how time outdoors was captured, and the distinction between direct vs. indirect sunlight. Participants with EPP also noted these items needed revision, and that the distinction between prodromal symptoms and full reaction symptoms should be clarified. In the final diary version, participants with EPP found most items to be clear and easy to complete/think about. Seventy-six percent of participants (13/17) asked thought the diary was easy to complete. The remainder thought the majority of the diary was easy to complete with the exception of select questions.

CONCLUSIONS: Evaluating a new treatment for EPP requires accurately capturing time in sunlight and symptoms in this unique disorder. The newly developed sun exposure diary is content valid and can be used to assess important aspects of symptoms and daily life and therefore evaluate clinically meaningful therapeutic response.

PMID:37982964 | DOI:10.1186/s41687-023-00655-y

Categories: Literature Watch

Trends in Hospitalization Duration for Rare Diseases: A Retrospective Analysis of Sarcoidosis, Still's Disease, and Systemic Sclerosis in Poland (2009-2018)

Mon, 2023-11-20 06:00

Med Sci Monit. 2023 Nov 20;29:e941536. doi: 10.12659/MSM.941536.

ABSTRACT

BACKGROUND A rare disease is a health condition that rarely occurs in the population. It is estimated that up to 400 million people around the world suffer from a rare disease. This retrospective study aimed to investigate factors associated with length of hospitalization in 78 626 patients with sarcoidosis, 3294 patients with adults-onset Still's disease, and 35 549 patients with systemic sclerosis between 2009 and 2018 using data from the National Institute of Public Health in Poland. MATERIAL AND METHODS In this population-based study, we analyzed hospital discharge records of first-time and subsequent hospitalizations. To perform the statistical analyses, R software was used. RESULTS The average length of hospitalization over the selected period in the diseases was 5.39 days for sarcoidosis, 6.22 days for scleroderma, and 7.44 days for Still's disease, and was shorter for each of the diseases analyzed compared with the length of hospitalization for second and subsequent stays. There were no substantial differences in length of hospitalization between males and females. The average length of hospitalization increased with each additional comorbidity. CONCLUSIONS The study showed that hospitalizations for selected rare diseases do not cause a significant burden on the healthcare system. The results also showed that advanced age and comorbidities are important factors determining the length of hospitalization. The average length of hospital stay for selected rare diseases in Poland is not longer than the European Union (EU) average, so it can be assumed that the process of inpatient treatment in Poland is optimal.

PMID:37981760 | DOI:10.12659/MSM.941536

Categories: Literature Watch

Towards personalized genome-scale modeling of inborn errors of metabolism for systems medicine applications

Sun, 2023-11-19 06:00

Metabolism. 2024 Jan;150:155738. doi: 10.1016/j.metabol.2023.155738. Epub 2023 Nov 18.

ABSTRACT

Inborn errors of metabolism (IEMs) are a group of more than 1000 inherited diseases that are individually rare but have a cumulative global prevalence of 50 per 100,000 births. Recently, it has been recognized that like common diseases, patients with rare diseases can greatly vary in the manifestation and severity of symptoms. Here, we review omics-driven approaches that enable an integrated, holistic view of metabolic phenotypes in IEM patients. We focus on applications of Constraint-based Reconstruction and Analysis (COBRA), a widely used mechanistic systems biology approach, to model the effects of inherited diseases. Moreover, we review evidence that the gut microbiome is also altered in rare diseases. Finally, we outline an approach using personalized metabolic models of IEM patients for the prediction of biomarkers and tailored therapeutic or dietary interventions. Such applications could pave the way towards personalized medicine not just for common, but also for rare diseases.

PMID:37981189 | DOI:10.1016/j.metabol.2023.155738

Categories: Literature Watch

Estimating mortality in rare diseases using a population-based registry, 2002 through 2019

Sat, 2023-11-18 06:00

Orphanet J Rare Dis. 2023 Nov 17;18(1):362. doi: 10.1186/s13023-023-02944-7.

ABSTRACT

BACKGROUND: Rare diseases (RD) are a heterogeneous group of diseases, sharing aspects of complexity. Prognosis is variable, even in individuals with the same disease. Real-world data on RD as a whole are scarce. The aim of this study is to provide data on mortality and survival for a substantial group of RD deriving from a population-based registry, which covers the Veneto region in Italy (4.9 million inhabitants).

RESULTS: During the study period, 3367 deaths occurred, mainly in males (53.9%), elderly patients (63.5%) and patients with diseases having a reported prevalence of 1-9/100000 (65.6%). When standardizing by age, the mortality ratio was higher in RD patients than in the general population, SMR = 1.93 (95% CI 1.84-2.11), with an observed gender difference, 2.01 (95% CI 1.88-2.29) in females and 1.86 (95% CI 1.73-2.10) in males. The lowest survival rates are experienced by patients with rare neurologic diseases, rare skin diseases and rare systemic or rheumatologic diseases, 58%, 68% and 81%, respectively, after a 15-year observation period. It should be noted that only 18% of patients diagnosed with motor neuron diseases were alive after 15 years from diagnosis.

CONCLUSIONS: Despite progress in diagnosis, treatment and care in recent years, RD patients globally have higher mortality rates and reduced survival compared to the general population, with specific variations according to gender, age and disease group.

PMID:37978388 | PMC:PMC10655462 | DOI:10.1186/s13023-023-02944-7

Categories: Literature Watch

Les journées caribéennes des maladies rares et orphelines 2022

Fri, 2023-11-17 06:00

Med Sci (Paris). 2023 Nov;39 Hors série n° 1:67-71. doi: 10.1051/medsci/2023138. Epub 2023 Nov 17.

NO ABSTRACT

PMID:37975776 | DOI:10.1051/medsci/2023138

Categories: Literature Watch

Safety and efficacy of gene replacement therapy for X-linked myotubular myopathy (ASPIRO): a multinational, open-label, dose-escalation trial

Fri, 2023-11-17 06:00

Lancet Neurol. 2023 Dec;22(12):1125-1139. doi: 10.1016/S1474-4422(23)00313-7.

ABSTRACT

BACKGROUND: X-linked myotubular myopathy is a rare, life-threatening, congenital muscle disease observed mostly in males, which is caused by mutations in MTM1. No therapies are approved for this disease. We aimed to assess the safety and efficacy of resamirigene bilparvovec, which is an adeno-associated viral vector serotype 8 delivering human MTM1.

METHODS: ASPIRO is an open-label, dose-escalation trial at seven academic medical centres in Canada, France, Germany, and the USA. We included boys younger than 5 years with X-linked myotubular myopathy who required mechanical ventilator support. The trial was initially in two parts. Part 1 was planned as a safety and dose-escalation phase in which participants were randomly allocated (2:1) to either the first dose level (1·3 × 1014 vector genomes [vg]/kg bodyweight) of resamirigene bilparvovec or delayed treatment, then, for later participants, to either a higher dose (3·5 × 1014 vg/kg bodyweight) of resamirigene bilparvovec or delayed treatment. Part 2 was intended to confirm the dose selected in part 1. Resamirigene bilparvovec was administered as a single intravenous infusion. An untreated control group comprised boys who participated in a run-in study (INCEPTUS; NCT02704273) or those in the delayed treatment cohort who did not receive any dose. The primary efficacy outcome was the change from baseline to week 24 in hours of daily ventilator support. After three unexpected deaths, dosing at the higher dose was stopped and the two-part feature of the study design was eliminated. Because of changes to the study design during its implementation, analyses were done on an as-treated basis and are deemed exploratory. All treated and control participants were included in the safety analysis. The trial is registered with ClinicalTrials.gov, NCT03199469. Outcomes are reported as of Feb 28, 2022. ASPIRO is currently paused while deaths in dosed participants are investigated.

FINDINGS: Between Aug 3, 2017 and June 1, 2021, 30 participants were screened for eligibility, of whom 26 were enrolled; six were allocated to the lower dose, 13 to the higher dose, and seven to delayed treatment. Of the seven children whose treatment was delayed, four later received the higher dose (n=17 total in the higher dose cohort), one received the lower dose (n=7 total in the lower dose cohort), and two received no dose and joined the control group (n=14 total, including 12 children from INCEPTUS). Median age at dosing or enrolment was 12·1 months (IQR 10·0-30·9; range 9·5-49·7) in the lower dose cohort, 31·1 months (16·0-64·7; 6·8-72·7) in the higher dose cohort, and 18·7 months (10·1-31·5; 5·9-39·3) in the control cohort. Median follow-up was 46·1 months (IQR 41·0-49·5; range 2·1-54·7) for lower dose participants, 27·6 months (24·6-29·1; 3·4-41·0) for higher dose participants, and 28·3 months (9·7-46·9; 5·7-32·7) for control participants. At week 24, lower dose participants had an estimated 77·7 percentage point (95% CI 40·22 to 115·24) greater reduction in least squares mean hours per day of ventilator support from baseline versus controls (p=0·0002), and higher dose participants had a 22·8 percentage point (6·15 to 39·37) greater reduction from baseline versus controls (p=0·0077). One participant in the lower dose cohort and three in the higher dose cohort died; at the time of death, all children had cholestatic liver failure following gene therapy (immediate causes of death were sepsis; hepatopathy, severe immune dysfunction, and pseudomonal sepsis; gastrointestinal haemorrhage; and septic shock). Three individuals in the control group died (haemorrhage presumed related to hepatic peliosis; aspiration pneumonia; and cardiopulmonary failure).

INTERPRETATION: Most children with X-linked myotubular myopathy who received MTM1 gene replacement therapy had important improvements in ventilator dependence and motor function, with more than half of dosed participants achieving ventilator independence and some attaining the ability to walk independently. Investigations into the risk for underlying hepatobiliary disease in X-linked myotubular myopathy, and the need for monitoring of liver function before gene replacement therapy, are ongoing.

FUNDING: Astellas Gene Therapies.

PMID:37977713 | DOI:10.1016/S1474-4422(23)00313-7

Categories: Literature Watch

Clinicopathological Features and Management Principles of Tracheobronchopathia Osteochondroplastica - A Scoping Review

Fri, 2023-11-17 06:00

Indian J Otolaryngol Head Neck Surg. 2023 Dec;75(4):3798-3814. doi: 10.1007/s12070-023-03998-6. Epub 2023 Jul 10.

ABSTRACT

Tracheobronchopathia osteochondroplastica (TO) is an orphan disease of the tracheobronchial tree without any known etiological attributes. There are several case reports published on this condition, yet the available information about the TO is discrete and of little clinical value. This scoping review is the first large-scale review on TO that collates individual patient data from the published case reports and descriptively analyses the clinicopathological features of this unique condition along with its management approaches and therapeutic outcomes. The objective was to synthesize comprehensive literature review on TO that can aid clinical practice and further research. An electronic search conducted in five large databases, including PubMed, EMBASE, CINAHL, CENTRAL, and Web of Science, for the published articles of TO yielded 1072 items. After screening, the individual patient data of 371 TO cases from 228 eligible articles were included and analysed in this scoping review.

SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12070-023-03998-6.

PMID:37974722 | PMC:PMC10646011 | DOI:10.1007/s12070-023-03998-6

Categories: Literature Watch

The Hepatic Porphyrias: Revealing the Complexities of a Rare Disease

Thu, 2023-11-16 06:00

Semin Liver Dis. 2023 Nov;43(4):446-459. doi: 10.1055/s-0043-1776760. Epub 2023 Nov 16.

ABSTRACT

The porphyrias are a group of metabolic disorders that are caused by defects in heme biosynthesis pathway enzymes. The result is accumulation of heme precursors, which can cause neurovisceral and/or cutaneous photosensitivity. Liver is commonly either a source or target of excess porphyrins, and porphyria-associated hepatic dysfunction ranges from minor abnormalities to liver failure. In this review, the first of a three-part series, we describe the defects commonly found in each of the eight enzymes involved in heme biosynthesis. We also discuss the pathophysiology of the hepatic porphyrias in detail, covering epidemiology, histopathology, diagnosis, and complications. Cellular consequences of porphyrin accumulation are discussed, with an emphasis on oxidative stress, protein aggregation, hepatocellular cancer, and endothelial dysfunction. Finally, we review current therapies to treat and manage symptoms of hepatic porphyria.

PMID:37973028 | DOI:10.1055/s-0043-1776760

Categories: Literature Watch

Gastrointestinal manifestations in pediatric and adult patients with Rett syndrome: an analysis of US claims and physician survey data

Thu, 2023-11-16 06:00

J Comp Eff Res. 2023 Nov 16:e230054. doi: 10.57264/cer-2023-0054. Online ahead of print.

ABSTRACT

Aim: Patients with Rett syndrome (RTT) experience gastrointestinal (GI) manifestations. This study aimed to describe the prevalence of GI manifestations and the associated medical costs in patients with RTT in the USA. Patients & Methods: The study combined an insurance claims database analysis with a survey of 100 physicians experienced in RTT management. Results: GI manifestations affected 43.0% of 5940 patients, with increased prevalence in pediatric patients (45.6%) relative to adult patients (40.2%). Annualized mean medical cost of managing GI manifestations was $4473. Only 5.9-8.2% of neurologists and pediatricians ranked GI symptom management among the five most important treatment goals. Conclusion: Patients with RTT experience a high burden of GI manifestations, which translate to considerable medical costs. Importantly, the prevalence of GI manifestations was likely underestimated in this study, as only those symptoms which resulted in a healthcare encounter were captured.

PMID:37971297 | DOI:10.57264/cer-2023-0054

Categories: Literature Watch

The Medical Action Ontology: A tool for annotating and analyzing treatments and clinical management of human disease

Tue, 2023-11-14 06:00

Med. 2023 Dec 8;4(12):913-927.e3. doi: 10.1016/j.medj.2023.10.003. Epub 2023 Nov 13.

ABSTRACT

BACKGROUND: Navigating the clinical literature to determine the optimal clinical management for rare diseases presents significant challenges. We introduce the Medical Action Ontology (MAxO), an ontology specifically designed to organize medical procedures, therapies, and interventions.

METHODS: MAxO incorporates logical structures that link MAxO terms to numerous other ontologies within the OBO Foundry. Term development involves a blend of manual and semi-automated processes. Additionally, we have generated annotations detailing diagnostic modalities for specific phenotypic abnormalities defined by the Human Phenotype Ontology (HPO). We introduce a web application, POET, that facilitates MAxO annotations for specific medical actions for diseases using the Mondo Disease Ontology.

FINDINGS: MAxO encompasses 1,757 terms spanning a wide range of biomedical domains, from human anatomy and investigations to the chemical and protein entities involved in biological processes. These terms annotate phenotypic features associated with specific disease (using HPO and Mondo). Presently, there are over 16,000 MAxO diagnostic annotations that target HPO terms. Through POET, we have created 413 MAxO annotations specifying treatments for 189 rare diseases.

CONCLUSIONS: MAxO offers a computational representation of treatments and other actions taken for the clinical management of patients. Its development is closely coupled to Mondo and HPO, broadening the scope of our computational modeling of diseases and phenotypic features. We invite the community to contribute disease annotations using POET (https://poet.jax.org/). MAxO is available under the open-source CC-BY 4.0 license (https://github.com/monarch-initiative/MAxO).

FUNDING: NHGRI 1U24HG011449-01A1 and NHGRI 5RM1HG010860-04.

PMID:37963467 | DOI:10.1016/j.medj.2023.10.003

Categories: Literature Watch

Study methodology and insights from the palovarotene clinical development program in fibrodysplasia ossificans progressiva

Tue, 2023-11-14 06:00

BMC Med Res Methodol. 2023 Nov 13;23(1):269. doi: 10.1186/s12874-023-02080-7.

ABSTRACT

BACKGROUND: The design of clinical trials in rare diseases is often complicated by a lack of real-world translational knowledge. Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare genetic disorder characterized by skeletal malformations and progressive heterotopic ossification (HO). Palovarotene is a selective retinoic acid receptor gamma agonist. Here, we describe the methodology of three studies in the palovarotene clinical development program in FOP and discuss insights that could inform future research, including endpoint suitability and the impact of trial design.

METHODS: PVO-1A-001 (NCT02322255) was a prospective, protocol-specified, longitudinal FOP natural history study (NHS). PVO-1A-201 (NCT02190747) was a randomized, double-blind, placebo-controlled phase II trial; PVO-1A-202 (NCT02279095) was its open-label extension. Trial designs, including treatment regimens and imaging assessments, were refined between PVO-1A-201 and PVO-‍1A-202, and within PVO-1A-202, based on emerging data as the studies progressed. Palovarotene doses were administered using a flare-up treatment regimen (higher dose for 2/4 weeks, followed by lower dose for 4/≥8 weeks; from flare-up onset), with or without accompanying chronic (daily) treatment. Flare-up and disease progression outcomes were assessed, including incidence and volume of new HO during flare-ups and/or annually, as well as other clinical, patient-reported, and exploratory outcomes. Safety was monitored throughout all studies.

RESULTS: Overall, 114 and 58 individuals with FOP were enrolled in the NHS and phase II trials, respectively. Results of the NHS and PVO-1A-201 were published in 2022; complete results of PVO-1A-202 will be publicly available in due course. Together the studies yielded important information on endpoint suitability, including that low-dose whole-body computed tomography was the optimum imaging modality for assessing HO progression annually and that long study durations are needed to detect substantial changes in functional and patient-reported outcomes.

CONCLUSIONS: A flexible clinical development program is necessary for underexplored rare diseases to overcome the many challenges faced. Here, the NHS provided a longitudinal evaluation of FOP progression and interventional trials were based on emerging data. The studies described informed the design and endpoints implemented in the phase III MOVE trial (NCT03312634) and provide a foundation for future clinical trial development.

TRIAL REGISTRATION: NCT02322255 (registered 23/12/2014); NCT02190747 (registered 15/07/2014); NCT02279095 (registered 30/10/2014).

PMID:37957586 | DOI:10.1186/s12874-023-02080-7

Categories: Literature Watch

Branched-Chain Amino Acid Assembly into Amyloid-like Fibrils Provides a New Paradigm for Maple Syrup Urine Disease Pathology

Tue, 2023-11-14 06:00

Int J Mol Sci. 2023 Nov 6;24(21):15999. doi: 10.3390/ijms242115999.

ABSTRACT

Inborn error of metabolism disorders (IEMs) are a family of diseases resulting from single-gene mutations that lead to the accumulation of metabolites that are usually toxic or interfere with normal cell function. The etiological link between metabolic alteration and the symptoms of IEMs is still elusive. Several metabolites, which accumulate in IEMs, were shown to self-assemble to form ordered structures. These structures display the same biophysical, biochemical, and biological characteristics as proteinaceous amyloid fibrils. Here, we have demonstrated, for the first time, the ability of each of the branched-chain amino acids (BCAAs) that accumulate in maple syrup urine disease (MSUD) to self-assemble into amyloid-like fibrils depicted by characteristic morphology, binding to indicative amyloid-specific dyes and dose-dependent cytotoxicity by a late apoptosis mechanism. We could also detect the presence of the assemblies in living cells. In addition, by employing several in vitro techniques, we demonstrated the ability of known polyphenols to inhibit the formation of the BCAA fibrils. Our study implies that BCAAs possess a pathological role in MSUD, extends the paradigm-shifting concept regarding the toxicity of metabolite amyloid-like structures, and suggests new pathological targets that may lead to highly needed novel therapeutic opportunities for this orphan disease.

PMID:37958982 | DOI:10.3390/ijms242115999

Categories: Literature Watch

The Ehlers Danlos syndrome : a rare disease although commonly suspected

Mon, 2023-11-13 06:00

Rev Med Liege. 2023 Nov;78(11):626-633.

ABSTRACT

The Ehlers Danlos syndromes (EDS) are a heterogenous group of inherited connective tissue disorders characterized by generalized joint hypermobility and instability, tissue fragility and multiple functional disorders. The EDS hypermobility type (hEDS) is the most common but the mildest subtype of EDS and is defined by joint involvement. hSED diagnosis is based on clinical criteria because no genetic factors nor molecular basis have yet been identified. Since chronic pain constitutes one of hESD main symptoms, the diagnosis is frequently suspected although the syndrome is rare, with a prevalence estimated to be 1/10.000. An expert clinical evaluation is therefore necessary in order to establish an accurate diagnosis. This allows the implementation of physical therapy which is the only treatment that has proven efficacious in reducing joint instability, generalized pain and secondary osteoarthritis.

PMID:37955292

Categories: Literature Watch

Of Horses, Zebras, and the Diagnostic Process

Sat, 2023-11-11 06:00

Med Clin North Am. 2024 Jan;108(1):xv-xvi. doi: 10.1016/j.mcna.2023.09.001. Epub 2023 Sep 19.

NO ABSTRACT

PMID:37951659 | DOI:10.1016/j.mcna.2023.09.001

Categories: Literature Watch

Discovering Undiagnosed and Rare Diseases and their Mimics

Sat, 2023-11-11 06:00

Med Clin North Am. 2024 Jan;108(1):xvii-xviii. doi: 10.1016/j.mcna.2023.06.019. Epub 2023 Jul 19.

NO ABSTRACT

PMID:37951660 | DOI:10.1016/j.mcna.2023.06.019

Categories: Literature Watch

Attaining Diagnostic Excellence: How the Structure and Function of a Rare Disease Service Contribute to Ending the Diagnostic Odyssey

Sat, 2023-11-11 06:00

Med Clin North Am. 2024 Jan;108(1):1-14. doi: 10.1016/j.mcna.2023.06.013. Epub 2023 Jul 26.

ABSTRACT

Patients with rare or otherwise undiagnosed disorders frequently find themselves on a diagnostic odyssey, the often-prolonged journey toward diagnosis that can be characterized by significant physical, emotional, and financial hardship, as well as by diagnostic errors and delays. The wider availability of clinical exome sequencing has helped end many diagnostic odysseys, though diagnostic success rates of around 35% for exome sequencing leave many patients undiagnosed. Diagnostic yields can be improved via the implementation of advanced genetic testing modalities, though both these modalities and exome sequencing perform significantly better when paired with high-quality phenotypic data. Diagnostic centers of excellence can improve outcomes for patients on a diagnostic odyssey by providing a process and environment that address shortfalls in diagnostic access while providing high-quality phenotyping. Features of successful undiagnosed and rare disease evaluation teams are discussed and an illustrative case is provided.

PMID:37951644 | DOI:10.1016/j.mcna.2023.06.013

Categories: Literature Watch

Pages