Orphan or Rare Diseases
Oxalate: from physiology to pathology
Nephrol Ther. 2023 May 11;19(3):1-14. doi: 10.1684/ndt.2023.10. Online ahead of print.
ABSTRACT
Hyperoxaluria is defined by an increase of urinary oxalate, leading to kidney stones, nephrocalcinosis and/or chronic kidney disease. There are different diseases related to hyperoxaluria: (1) kidney stones, 50% of them being explained by intermittent hyperoxaluria, secondary to dietary mistakes such as low hydration, excess of oxalate consumption and/or low calcium consumption; (2) primary hyperoxaluria, a genetic orphan disease inducing a massive production of oxalate by the liver, leading to increased plasma oxalate increase and saturation, and further systemic oxalosis with oxalate deposition, nephrocalcinosis and ultimately kidney failure, the management of this disease being currently dramatically modified by the onset of new therapeutic tools such as RNA interference; and (3) enteric hyperoxaluria, resulting from increased intestinal oxalate absorption because of intestinal malabsorption (short bowel syndrome, bariatric surgery, exocrine pancreatic insufficiency, etc.). Diagnosis and therapeutic management of these diseases require a full understanding of oxalate physiology that we detail in this review.
PMID:37166780 | DOI:10.1684/ndt.2023.10
Exacerbation Prevention and Management of Bronchiectasis
Tuberc Respir Dis (Seoul). 2023 May 10. doi: 10.4046/trd.2023.0010. Online ahead of print.
ABSTRACT
Bronchiectasis is characterized by irreversibly damaged and dilated bronchi, which causes significant symptoms, poor quality of life, increased economic burden and mortality rates. Despite increasing prevalence and clinical significance of bronchiectasis, bronchiectasis was previously regarded as an orphan disease, and ideal treatment of this disease have been poorly understood. European Respiratory Society and British Thoracic Society have recently published guidelines to assist physicians in the clinical field. Guidelines and reports suggest comprehensive management including both non-pharmacological and pharmacological treatments. Physiotherapy and pulmonary rehabilitation are one of the most important non-pharmacologic therapies in bronchiectasis patients; long-term inhaled antibiotics and macrolide therapy have gained significant evidences in reducing exacerbation risk in frequent exacerbators. In this review, we summarized recent update on bronchiectasis treatment to prevent exacerbation and management of clinical deteriorations.
PMID:37165624 | DOI:10.4046/trd.2023.0010
Cell survival pathways targeted in rare lung disease affecting women
Sci Adv. 2023 May 10;9(19):eadi1215. doi: 10.1126/sciadv.adi1215. Epub 2023 May 10.
ABSTRACT
Novel drug targets are identified in lymphangioleiomyomatosis (LAM), a rare disease in women. These targets focus on uterine transcription factors necessary for LAM cell survival.
PMID:37163598 | DOI:10.1126/sciadv.adi1215
Towards the international interoperability of clinical research networks for rare diseases: recommendations from the IRDiRC Task Force
Orphanet J Rare Dis. 2023 May 9;18(1):109. doi: 10.1186/s13023-023-02650-4.
ABSTRACT
BACKGROUND: Many patients with rare diseases are still lacking a timely diagnosis and approved therapies for their condition despite the tremendous efforts of the research community, biopharmaceutical, medical device industries, and patient support groups. The development of clinical research networks for rare diseases offers a tremendous opportunity for patients and multi-disciplinary teams to collaborate, share expertise, gain better understanding on specific rare diseases, and accelerate clinical research and innovation. Clinical Research Networks have been developed at a national or continental level, but global collaborative efforts to connect them are still lacking. The International Rare Diseases Research Consortium set a Task Force on Clinical Research Networks for Rare Diseases with the objective to analyse the structure and attributes of these networks and to identify the barriers and needs preventing their international collaboration. The Task Force created a survey and sent it to pre-identified clinical research networks located worldwide.
RESULTS: A total of 34 responses were received. The survey analysis demonstrated that clinical research networks are diverse in their membership composition and emphasize community partnerships including patient groups, health care providers and researchers. The sustainability of the networks is mostly supported by public funding. Activities and research carried out at the networks span the research continuum from basic to clinical to translational research studies. Key elements and infrastructures conducive to collaboration are well adopted by the networks, but barriers to international interoperability are clearly identified. These hurdles can be grouped into five categories: funding limitation; lack of harmonization in regulatory and contracting process; need for common tools and data standards; need for a governance framework and coordination structures; and lack of awareness and robust interactions between networks.
CONCLUSIONS: Through this analysis, the Task Force identified key elements that should support both developing and established clinical research networks for rare diseases in implementing the appropriate structures to achieve international interoperability worldwide. A global roadmap of actions and a specific research agenda, as suggested by this group, provides a platform to identify common goals between these networks.
PMID:37161573 | DOI:10.1186/s13023-023-02650-4
FDA approval, clinical trial evidence, efficacy, epidemiology, and price for non-orphan and ultra-rare, rare, and common orphan cancer drug indications: cross sectional analysis
BMJ. 2023 May 9;381:e073242. doi: 10.1136/bmj-2022-073242.
ABSTRACT
OBJECTIVE: To analyze the US Food and Drug Administration (FDA) approval, trials, unmet needs, benefit, and pricing of ultra-rare (<6600 affected US citizens), rare (6600-200 000 citizens), and common (>200 000 citizens) orphan cancer drug indications and non-orphan cancer drug indications.
DESIGN: Cross sectional analysis.
SETTING: Data from Drugs@FDA, FDA labels, Global Burden of Disease study, and Medicare and Medicaid.
POPULATION: 170 FDA approved drugs across 455 cancer indications between 2000 and 2022.
MAIN OUTCOME MEASURES: Comparison of non-orphan and ultra-rare, rare, and common orphan indications regarding regulatory approval, trials, epidemiology, and price. Hazard ratios for overall survival and progression-free survival were meta-analyzed.
RESULTS: 161 non-orphan and 294 orphan cancer drug indications were identified, of which 25 were approved for ultra-rare diseases, 205 for rare diseases, and 64 for common diseases. Drugs for ultra-rare orphan indications were more frequently first in class (76% v 48% v 38% v 42%; P<0.001), monotherapies (88% v 69% v 72% v 55%; P=0.001), for hematologic cancers (76% v 66% v 0% v 0%; P<0.001), and supported by smaller trials (median 85 v 199 v 286 v 521 patients; P<0.001), of single arm (84% v 44% v 28% v 21%; P<0.001) phase 1/2 design (88% v 45% v 45% v 27%; P<0.001) compared with rare and common orphan indications and non-orphan indications. Drugs for common orphan indications were more often biomarker directed (69% v 26% v 12%; P<0.001), first line (77% v 39% v 20%; P<0.001), small molecules (80% v 62% v 48%; P<0.001) benefiting from quicker time to first FDA approval (median 5.7 v 7.1 v 8.9 years; P=0.02) than those for rare and ultra-rare orphan indications. Drugs for ultra-rare, rare, and common orphan indications offered a significantly greater progression-free survival benefit (hazard ratio 0.53 v 0.51 v 0.49 v 0.64; P<0.001), but not overall survival benefit (0.50 v 0.73 v 0.71 v 0.74; P=0.06), than non-orphans. In single arm trials, tumor response rates were greater for drugs for ultra-rare orphan indications than for rare or common orphan indications and non-orphan indications (objective response rate 57% v 48% v 55% v 33%; P<0.001). Disease incidence/prevalence, five year survival, and the number of available treatments were lower, whereas disability adjusted life years per patient were higher, for ultra-rare orphan indications compared with rare or common indications and non-orphan indications. For 147 on-patent drugs with available data in 2023, monthly prices were higher for ultra-rare orphan indications than for rare or common orphan indications and non-orphan indications ($70 128 (£55 971; €63 370) v $33 313 v $16 484 v $14 508; P<0.001). For 48 on-patent drugs with available longitudinal data from 2005 to 2023, prices increased by 94% for drugs for orphan indications and 50% for drugs for non-orphan indications on average.
CONCLUSIONS: The Orphan Drug Act of 1983 incentivizes development of drugs not only for rare diseases but also for ultra-rare diseases and subsets of common diseases. These orphan indications fill significant unmet needs, yet their approval is based on small, non-robust trials that could overestimate efficacy outcomes. A distinct ultra-orphan designation with greater financial incentives could encourage and expedite drug development for ultra-rare diseases.
PMID:37160306 | DOI:10.1136/bmj-2022-073242
Reforming EU and national orphan drug regulations to improve outcomes for patients with rare diseases
BMJ. 2023 May 9;381:e072796. doi: 10.1136/bmj-2022-072796.
NO ABSTRACT
PMID:37160303 | DOI:10.1136/bmj-2022-072796
Not a pneumothorax again! Birt-Hogg-Dubé syndrome: a case report
Pneumologie. 2023 May;77(5):303-307. doi: 10.1055/a-2028-6032. Epub 2023 May 9.
ABSTRACT
Case discussion of a 40-year-old male patient with a history of recurrent pneumothoraces due to Birt-Hogg-Dubé syndrome. In addition to conservative treatment of a pneumothorax on the left side, a subtotal parietal pleurectomy on the right side was performed after recurrence of a pneumothorax 6 years later. CT of the thorax showed high-grade structural remodelling of the lung parenchyma with cystic lung lesions on both sides with a diameter of up to 7.5 cm. After exclusion of alpha-1 antitrypsin deficiency, underlying immunological disease, unremarkable family and occupational history, Birt-Hogg-Dubé syndrome was suspected based on the morphological distribution pattern of the cystic lung lesions. Genetic examination helped detect a heterozygous pathogenic variant in the FLCN gene, namely c.1294_1298del;p.(Ser432Argfs*22). Birt-Hogg-Dubé syndrome is a rare genetic disorder clinically characterized by pulmonary cysts, fibrofolliculomas of the skin and occurrence of clustered renal tumors. In particular, the increased risk of renal malignancies and the risk of spontaneous pneumothoraces underlines the importance of early diagnosis and screening of affected patients and their families.
PMID:37160111 | DOI:10.1055/a-2028-6032
Perspectives of Rare Disease Experts on Newborn Genome Sequencing
JAMA Netw Open. 2023 May 1;6(5):e2312231. doi: 10.1001/jamanetworkopen.2023.12231.
ABSTRACT
IMPORTANCE: Newborn genome sequencing (NBSeq) can detect infants at risk for treatable disorders currently undetected by conventional newborn screening. Despite broad stakeholder support for NBSeq, the perspectives of rare disease experts regarding which diseases should be screened have not been ascertained.
OBJECTIVE: To query rare disease experts about their perspectives on NBSeq and which gene-disease pairs they consider appropriate to evaluate in apparently healthy newborns.
DESIGN, SETTING, AND PARTICIPANTS: This survey study, designed between November 2, 2021, and February 11, 2022, assessed experts' perspectives on 6 statements related to NBSeq. Experts were also asked to indicate whether they would recommend including each of 649 gene-disease pairs associated with potentially treatable conditions in NBSeq. The survey was administered between February 11 and September 23, 2022, to 386 experts, including all 144 directors of accredited medical and laboratory genetics training programs in the US.
EXPOSURES: Expert perspectives on newborn screening using genome sequencing.
MAIN OUTCOMES AND MEASURES: The proportion of experts indicating agreement or disagreement with each survey statement and those who selected inclusion of each gene-disease pair were tabulated. Exploratory analyses of responses by gender and age were conducted using t and χ2 tests.
RESULTS: Of 386 experts invited, 238 (61.7%) responded (mean [SD] age, 52.6 [12.8] years [range 27-93 years]; 126 [52.9%] women and 112 [47.1%] men). Among the experts who responded, 161 (87.9%) agreed that NBSeq for monogenic treatable disorders should be made available to all newborns; 107 (58.5%) agreed that NBSeq should include genes associated with treatable disorders, even if those conditions were low penetrance; 68 (37.2%) agreed that actionable adult-onset conditions should be sequenced in newborns to facilitate cascade testing in parents, and 51 (27.9%) agreed that NBSeq should include screening for conditions with no established therapies or management guidelines. The following 25 genes were recommended by 85% or more of the experts: OTC, G6PC, SLC37A4, CYP11B1, ARSB, F8, F9, SLC2A1, CYP17A1, RB1, IDS, GUSB, DMD, GLUD1, CYP11A1, GALNS, CPS1, PLPBP, ALDH7A1, SLC26A3, SLC25A15, SMPD1, GATM, SLC7A7, and NAGS. Including these, 42 gene-disease pairs were endorsed by at least 80% of experts, and 432 genes were endorsed by at least 50% of experts.
CONCLUSIONS AND RELEVANCE: In this survey study, rare disease experts broadly supported NBSeq for treatable conditions and demonstrated substantial concordance regarding the inclusion of a specific subset of genes in NBSeq.
PMID:37155167 | PMC:PMC10167563 | DOI:10.1001/jamanetworkopen.2023.12231
An artificial intelligence-based approach for identifying rare disease patients using retrospective electronic health records applied for Pompe disease
Front Neurol. 2023 Apr 21;14:1108222. doi: 10.3389/fneur.2023.1108222. eCollection 2023.
ABSTRACT
OBJECTIVE: We retrospectively screened 350,116 electronic health records (EHRs) to identify suspected patients for Pompe disease. Using these suspected patients, we then describe their phenotypical characteristics and estimate the prevalence in the respective population covered by the EHRs.
METHODS: We applied Symptoma's Artificial Intelligence-based approach for identifying rare disease patients to retrospective anonymized EHRs provided by the "University Hospital Salzburg" clinic group. Within 1 month, the AI screened 350,116 EHRs reaching back 15 years from five hospitals, and 104 patients were flagged as probable for Pompe disease. Flagged patients were manually reviewed and assessed by generalist and specialist physicians for their likelihood for Pompe disease, from which the performance of the algorithms was evaluated.
RESULTS: Of the 104 patients flagged by the algorithms, generalist physicians found five "diagnosed," 10 "suspected," and seven patients with "reduced suspicion." After feedback from Pompe disease specialist physicians, 19 patients remained clinically plausible for Pompe disease, resulting in a specificity of 18.27% for the AI. Estimating from the remaining plausible patients, the prevalence of Pompe disease for the greater Salzburg region [incl. Bavaria (Germany), Styria (Austria), and Upper Austria (Austria)] was one in every 18,427 people. Phenotypes for patient cohorts with an approximated onset of symptoms above or below 1 year of age were established, which correspond to infantile-onset Pompe disease (IOPD) and late-onset Pompe disease (LOPD), respectively.
CONCLUSION: Our study shows the feasibility of Symptoma's AI-based approach for identifying rare disease patients using retrospective EHRs. Via the algorithm's screening of an entire EHR population, a physician had only to manually review 5.47 patients on average to find one suspected candidate. This efficiency is crucial as Pompe disease, while rare, is a progressively debilitating but treatable neuromuscular disease. As such, we demonstrated both the efficiency of the approach and the potential of a scalable solution to the systematic identification of rare disease patients. Thus, similar implementation of this methodology should be encouraged to improve care for all rare disease patients.
PMID:37153672 | PMC:PMC10160659 | DOI:10.3389/fneur.2023.1108222
A systematic overview of rare disease patient registries: challenges in design, quality management, and maintenance
Orphanet J Rare Dis. 2023 May 5;18(1):106. doi: 10.1186/s13023-023-02719-0.
ABSTRACT
Patient registries serve to overcome the research limitations inherent in the study of rare diseases, where patient numbers are typically small. Despite the value of real-world data collected through registries, adequate design and maintenance are integral to data quality. We aimed to describe an overview of the challenges in design, quality management, and maintenance of rare disease registries.A systematic search of English articles was conducted in PubMed, Ovid Medline/Embase, and Cochrane Library. Search terms included "rare diseases, patient registries, common data elements, quality, hospital information systems, and datasets". Inclusion criteria were any manuscript type focused upon rare disease patient registries describing design, quality monitoring or maintenance. Biobanks and drug surveillances were excluded.A total of 37 articles, published between 2001 and 2021, met the inclusion criteria. Patient registries covered a wide range of disease areas and covered multiple geographical locations, with a predisposition for Europe. Most articles were methodological reports and described the design and setup of a registry. Most registries recruited clinical patients (92%) with informed consent (81%) and protected the collected data (76%). Whilst the majority (57%) collected patient-reported outcome measures, only few (38%) consulted PAGs during the registry design process. Few reports described details regarding quality management (51%) and maintenance (46%).Rare disease patient registries are valuable for research and evaluation of clinical care, and an increasing number have emerged. However, registries need to be continuously evaluated for data quality and long-term sustainability to remain relevant for future use.
PMID:37147718 | PMC:PMC10163740 | DOI:10.1186/s13023-023-02719-0
Ontology-driven and weakly supervised rare disease identification from clinical notes
BMC Med Inform Decis Mak. 2023 May 5;23(1):86. doi: 10.1186/s12911-023-02181-9.
ABSTRACT
BACKGROUND: Computational text phenotyping is the practice of identifying patients with certain disorders and traits from clinical notes. Rare diseases are challenging to be identified due to few cases available for machine learning and the need for data annotation from domain experts.
METHODS: We propose a method using ontologies and weak supervision, with recent pre-trained contextual representations from Bi-directional Transformers (e.g. BERT). The ontology-driven framework includes two steps: (i) Text-to-UMLS, extracting phenotypes by contextually linking mentions to concepts in Unified Medical Language System (UMLS), with a Named Entity Recognition and Linking (NER+L) tool, SemEHR, and weak supervision with customised rules and contextual mention representation; (ii) UMLS-to-ORDO, matching UMLS concepts to rare diseases in Orphanet Rare Disease Ontology (ORDO). The weakly supervised approach is proposed to learn a phenotype confirmation model to improve Text-to-UMLS linking, without annotated data from domain experts. We evaluated the approach on three clinical datasets, MIMIC-III discharge summaries, MIMIC-III radiology reports, and NHS Tayside brain imaging reports from two institutions in the US and the UK, with annotations.
RESULTS: The improvements in the precision were pronounced (by over 30% to 50% absolute score for Text-to-UMLS linking), with almost no loss of recall compared to the existing NER+L tool, SemEHR. Results on radiology reports from MIMIC-III and NHS Tayside were consistent with the discharge summaries. The overall pipeline processing clinical notes can extract rare disease cases, mostly uncaptured in structured data (manually assigned ICD codes).
CONCLUSION: The study provides empirical evidence for the task by applying a weakly supervised NLP pipeline on clinical notes. The proposed weak supervised deep learning approach requires no human annotation except for validation and testing, by leveraging ontologies, NER+L tools, and contextual representations. The study also demonstrates that Natural Language Processing (NLP) can complement traditional ICD-based approaches to better estimate rare diseases in clinical notes. We discuss the usefulness and limitations of the weak supervision approach and propose directions for future studies.
PMID:37147628 | PMC:PMC10162001 | DOI:10.1186/s12911-023-02181-9
SARS-CoV-2-induced adrenal crisis in a patient with autoimmune polyglandular syndrome type 1: case report
Folia Med (Plovdiv). 2023 Apr 30;65(2):305-310. doi: 10.3897/folmed.65.e76245.
ABSTRACT
Autoimmune polyglandular syndromes (APS) are rare disorders characterized by the coexistence of endocrine and non-endocrine dysfunctions mediated by autoimmune mechanisms. Autoimmune polyglandular syndrome type 1 is defined as coexistence of chronic mucocutaneous candidiasis, hypoparathyroidism, and autoimmune adrenal insufficiency. Addison's disease as the obligatory component is potentially life threatening.Herein, we demonstrate a case of a 44-year-old woman with APS-1 (hypoparathyroidism, adrenal insufficiency, hypergonadotropic hypogonadism) and SARS-CoV-2-induced adrenal crisis. The patient presented with the typical manifestations of hypotensive shock, electrolyte disturbances of hyponatremia and hyperkalemia, and hypoglycaemia.Our case report illustrates the increased risk of severe course of COVID-19 in APS-1 syndrome patients along with heightened exposure to medical complications. The case reinforced the significance of a timely diagnosis, appropriate treatment, and education of patients with such a rare condition like APS-1.
PMID:37144317 | DOI:10.3897/folmed.65.e76245
Confronting complexity in the design and conduct of high-risk rare disease clinical trials
Mol Ther. 2023 May 3;31(5):1191-1192. doi: 10.1016/j.ymthe.2023.04.004.
NO ABSTRACT
PMID:37141855 | DOI:10.1016/j.ymthe.2023.04.004
Fatal dermatophytic pseudomycetoma in a patient with non-HIV CD4 lymphocytopenia
Emerg Microbes Infect. 2023 Dec;12(1):2208685. doi: 10.1080/22221751.2023.2208685.
ABSTRACT
Dermatophytic pseudomycetoma is a rare invasive infection, involving both immunocompetent and immunocompromised individuals. Since the discovery of inherited immune disorders such as the impairment of CARD9 gene, extended dermatophyte infections are mostly ascribed to any of these host factors. This study is to present and explore the potential causes in a fatal dermatophytic pseudomycetoma patient. We present a chronic and deep pseudomycetoma caused by the common dermatophyte Microsporum canis which ultimately led to the death of the patient. Mycological examination, genetic studies and host immune responses against fungi were performed to explore the potential factors. The patient had decreased lymphocyte counts with significantly reduced CD4+ T cells, although all currently known genetic parameters proved to be normal. Through functional studies, we demonstrated that peripheral blood mononuclear cells from the patient showed severe impairment of adaptive cytokine production upon fungus-specific stimulation, whereas innate immune responses were partially defective. This is, to our knowledge, the first report of fatal dermatophytic pseudomycetoma in a patient with non-HIV CD4 lymphocytopenia, which highlights the importance of screening for immune deficiencies in patients with deep dermatophytosis.
PMID:37128909 | PMC:PMC10193896 | DOI:10.1080/22221751.2023.2208685
Payer and provider solutions to utilization management challenges in the management of rare hematologic cancers
Am J Manag Care. 2023 Apr;29(4 Suppl):S51-S60. doi: 10.37765/ajmc.2023.89365.
ABSTRACT
Patients with rare diseases such as Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL), a hematologic malignancy affecting approximately 1500 new patients per year, experience barriers to care involving both clinical and administrative factors. Optimal patient outcomes depend on timely identification, diagnosis of disease, and treatment initiation. For patients living with Ph+ ALL, the process can be delayed by limited treatment options approved by the US Food and Drug Administration and administrative hurdles that often delay treatment initiation. An overhaul of utilization management processes, such as the requirement for prior authorization (PA) for treatment, are needed to ensure patients have access to appropriate treatments in a timely manner. An AJMC Roundtable in November 2022 brought together a panel of payers and providers to discuss the challenges and shortcomings of current PA processes and to present ideas for potential solutions for improving them. Panelists at the roundtable discussed approaches including the use of guideline-concordant electronic PAs and other digital solutions, expedited approval pathways for use in specific conditions, use of real-world evidence in decision-making, issuance of PA "Gold Cards" to select providers, and a shift to value-based care agreements. Roundtable attendees agreed that, regardless of the strategy for PA-process improvement, there is a need for improved communication between providers and payers to ensure that the decision-making system meets the essential need for timely patient access to optimal care. This article reviews utilization management and guideline-concordant care through the lens of rare diseases and then presents solutions to utilization.
PMID:37129958 | DOI:10.37765/ajmc.2023.89365
Characterizing Patient Representations for Computational Phenotyping
AMIA Annu Symp Proc. 2023 Apr 29;2022:319-328. eCollection 2022.
ABSTRACT
Patient representation learning methods create rich representations of complex data and have potential to further advance the development of computational phenotypes (CP). Currently, these methods are either applied to small predefined concept sets or all available patient data, limiting the potential for novel discovery and reducing the explainability of the resulting representations. We report on an extensive, data-driven characterization of the utility of patient representation learning methods for the purpose of CP development or automatization. We conducted ablation studies to examine the impact of patient representations, built using data from different combinations of data types and sampling windows on rare disease classification. We demonstrated that the data type and sampling window directly impact classification and clustering performance, and these results differ by rare disease group. Our results, although preliminary, exemplify the importance of and need for data-driven characterization in patient representation-based CP development pipelines.
PMID:37128436 | PMC:PMC10148332
Contribution of Somatic Ras/Raf/Mitogen-Activated Protein Kinase Variants in the Hippocampus in Drug-Resistant Mesial Temporal Lobe Epilepsy
JAMA Neurol. 2023 May 1. doi: 10.1001/jamaneurol.2023.0473. Online ahead of print.
ABSTRACT
IMPORTANCE: Mesial temporal lobe epilepsy (MTLE) is the most common focal epilepsy subtype and is often refractory to antiseizure medications. While most patients with MTLE do not have pathogenic germline genetic variants, the contribution of postzygotic (ie, somatic) variants in the brain is unknown.
OBJECTIVE: To test the association between pathogenic somatic variants in the hippocampus and MTLE.
DESIGN, SETTING, AND PARTICIPANTS: This case-control genetic association study analyzed the DNA derived from hippocampal tissue of neurosurgically treated patients with MTLE and age-matched and sex-matched neurotypical controls. Participants treated at level 4 epilepsy centers were enrolled from 1988 through 2019, and clinical data were collected retrospectively. Whole-exome and gene-panel sequencing (each genomic region sequenced more than 500 times on average) were used to identify candidate pathogenic somatic variants. A subset of novel variants was functionally evaluated using cellular and molecular assays. Patients with nonlesional and lesional (mesial temporal sclerosis, focal cortical dysplasia, and low-grade epilepsy-associated tumors) drug-resistant MTLE who underwent anterior medial temporal lobectomy were eligible. All patients with available frozen tissue and appropriate consents were included. Control brain tissue was obtained from neurotypical donors at brain banks. Data were analyzed from June 2020 to August 2022.
EXPOSURES: Drug-resistant MTLE.
MAIN OUTCOMES AND MEASURES: Presence and abundance of pathogenic somatic variants in the hippocampus vs the unaffected temporal neocortex.
RESULTS: Of 105 included patients with MTLE, 53 (50.5%) were female, and the median (IQR) age was 32 (26-44) years; of 30 neurotypical controls, 11 (36.7%) were female, and the median (IQR) age was 37 (18-53) years. Eleven pathogenic somatic variants enriched in the hippocampus relative to the unaffected temporal neocortex (median [IQR] variant allele frequency, 1.92 [1.5-2.7] vs 0.3 [0-0.9]; P = .01) were detected in patients with MTLE but not in controls. Ten of these variants were in PTPN11, SOS1, KRAS, BRAF, and NF1, all predicted to constitutively activate Ras/Raf/mitogen-activated protein kinase (MAPK) signaling. Immunohistochemical studies of variant-positive hippocampal tissue demonstrated increased Erk1/2 phosphorylation, indicative of Ras/Raf/MAPK activation, predominantly in glial cells. Molecular assays showed abnormal liquid-liquid phase separation for the PTPN11 variants as a possible dominant gain-of-function mechanism.
CONCLUSIONS AND RELEVANCE: Hippocampal somatic variants, particularly those activating Ras/Raf/MAPK signaling, may contribute to the pathogenesis of sporadic, drug-resistant MTLE. These findings may provide a novel genetic mechanism and highlight new therapeutic targets for this common indication for epilepsy surgery.
PMID:37126322 | DOI:10.1001/jamaneurol.2023.0473
Correlation Perspectives for the Diagnosis of Idiopathic Triglyceride Deposit Cardiomyovasculopathy
Ann Nucl Cardiol. 2020;6(1):33-38. doi: 10.17996/anc.20-00128. Epub 2020 Aug 31.
ABSTRACT
Background: Triglyceride (TG) deposit cardiomyovasculopathy (TGCV) is a novel cardiovascular disorder and was recently encoded as an orphan disease in Europe (ORPHA code: 565612). Defective lipolysis results in TG accumulation in the myocardium and coronary arteries in TGCV. The myocardial washout rate (WR) of iodine-123-β-methyl iodophenyl-pentadecanoic acid (BMIPP) is an essential indicator to evaluate myocardial lipolysis in vivo. TGCV is classified into primary and idiopathic type with and without PNPLA2 mutation, respectively. Here, we present the clinical correlation perspectives of TGCV patients in Chiba, Japan, to increase the awareness of this orphan disease and facilitate its diagnosis. Methods: We enrolled 234 patients who underwent BMIPP scintigraphy between September 2015 and July 2019. The diagnosis of TGCV was made based on the criteria we reported previously. Blood smear tests were performed for TGCV classification. The distributions of TGCV in each comorbidity were investigated. Results: In total, 104 patients were diagnosed with definitive idiopathic TGCV (I-TGCV). They had various comorbid conditions, including heart failure with reduced ejection fraction and multivessel coronary artery disease requiring revascularization. Moreover, the serum TG levels in I-TGCV patients were not high, and there was no correlation between serum TG level and BMIPP WR (n=205, p-value=0.31), supporting the pathophysiological hypothesis of TGCV. Conclusion: I-TGCV patients showed multiple coexistence of coronary artery disease, heart failure of unknown etiology, or diabetes mellitus. For patients with such clinical characteristics, BMIPP scintigraphy and calculation of WR should be considered proactively for the diagnosis of TGCV.
PMID:37123494 | PMC:PMC10133925 | DOI:10.17996/anc.20-00128
Strengths and limitations of new artificial intelligence tool for rare disease epidemiology
J Transl Med. 2023 Apr 30;21(1):292. doi: 10.1186/s12967-023-04152-0.
ABSTRACT
The recent paper by Kariampuzha et al. describes an exciting application of artificial intelligence to rare disease epidemiology. The authors' AI model appears to offer a major leap over Orphanet, the resource which is often a "first stop" for basic epidemiological data on rare diseases. To ensure appropriate use of this exciting tool, it is important to consider its strengths and weaknesses in context. The tool currently incorporates only PubMed abstracts, so key information located in the full text of articles is absent. Such missing information may include incidence and prevalence values, as well as important elements of study design and context. Additionally, results from the public version of the tool differ from those described in the original article, including obsolete values for prevalence and the use of non-prevalence studies in place of those listed in the article. At present, it would be appropriate to utilize the AI tool much like Orphanet: a helpful "first stop" which should be manually checked for completeness and accuracy. Users should understand the benefits of this exciting technology, and that it is not yet a panacea for the challenges of analyzing rare disease epidemiology.
PMID:37122037 | DOI:10.1186/s12967-023-04152-0
Esophageal papillomatosis: an exceedingly rare disease
Orphanet J Rare Dis. 2023 Apr 29;18(1):99. doi: 10.1186/s13023-023-02703-8.
ABSTRACT
If esophageal papilloma (EP) is a rare condition, esophageal papillomatosis (EPS) is a distinct rarity. To date, only 53 well documented cases have been described in English literature. However, the number of reports on EPS significantly increased to over 40 cases during the past 20 years. Perhaps, this is due to the broad use of endoscopy and related research achievements. Most of the cases are individual and it seems that there are no associations between them. And up to now no guidelines can be followed. To further understand this exceedingly rare disease, we had a comprehensive review of the epidemiology, etiology, clinical manifestations, pathogenesis, treatment, and clinical course of EPS.
PMID:37120568 | DOI:10.1186/s13023-023-02703-8