Orphan or Rare Diseases

Desmoid-type fibromatosis in the setting of malignant peritoneal mesothelioma: a case report of two rare diseases

Wed, 2022-09-28 06:00

World J Surg Oncol. 2022 Sep 28;20(1):317. doi: 10.1186/s12957-022-02784-y.

ABSTRACT

BACKGROUND: Desmoid-type fibromatosis (DTF) is a rare benign lesion that usually arises from the abdominal wall or extremities and rarely from the mesentery or intrabdominal organs. Malignant peritoneal mesothelioma is also a rare, yet aggressive disease. To our knowledge, this is the first case report of desmoid-type fibromatosis in the setting of malignant peritoneal mesothelioma.

CASE PRESENTATION: An early 30-year-old female was referred to our center for large intra-abdominal mass concerning for recurrent malignant peritoneal mesothelioma after previous cytoreductive surgery with hyperthermic intraperitoneal chemotherapy and adjuvant chemotherapy. Further investigation revealed a large mesenteric mass, which was resected en bloc with the cecum and terminal ileum. Pathologic findings confirmed a surprising diagnosis of desmoid-type fibromatosis.

CONCLUSIONS: No adjuvant therapy was offered to this patient due to negative tumor margins; however, close follow-up will be provided for recurrence of both malignant peritoneal mesothelioma and desmoid-type fibromatosis, which can be differentiated in the future via biopsy in this patient.

PMID:36171577 | DOI:10.1186/s12957-022-02784-y

Categories: Literature Watch

An Analysis of the Pathologic Features of Blastic Plasmacytoid Dendritic Cell Neoplasm Based on a Comprehensive Literature Database of Cases

Wed, 2022-09-28 06:00

Arch Pathol Lab Med. 2022 Sep 28. doi: 10.5858/arpa.2021-0612-RA. Online ahead of print.

ABSTRACT

CONTEXT.—: Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematologic malignancy with poor outcome. BPDCN diagnostically overlaps with entities such as acute myeloid leukemia, histiocytic/dendritic cell neoplasms, and natural killer/T-cell lymphomas. Unfortunately, large, patient-centered studies that comprehensively analyze clinical, pathologic, and other diagnostic features are lacking. As such, there is an incomplete understanding of this disease.

OBJECTIVE.—: To better characterize BPDCN, a multicenter working group consisting of hematopathologists and dermatopathologists gathered in person and remotely to review the current understanding of BPDCN, discuss specific issues regarding the diagnosis and differential diagnosis, and perform a retrospective analysis of the literature.

DATA SOURCES.—: The working group curated a database of published BPDCN patient cases (BPDCN Network literature database) following careful discussion and review, 361 articles were identified, comprising a total of 1513 individually annotated patients.

CONCLUSIONS.—: By conducting an in-depth analysis, not only did we confirm known findings such as frequent skin involvement (84% of patients; 861 of 1028) and a male predominance among older patients (>60 years old; male to female ratio of 3.5:1; 617:177), but we also identified a number of underrecognized features, such as significant central nervous system involvement (38% of cases; 24 of 64), and a more equal male to female prevalence among patients younger than 40 years (male to female ratio of 1.25:1; 167:134). Furthermore, we were able to accurately summarize the immunophenotypic, cytogenetic, and molecular features of this disease. BPDCN is a complex disease with distinct morphologic, immunophenotypic, and molecular findings. Continual updates of the literature database generated here and further analysis can allow for prospective refinement of our understanding of this orphan disease.

PMID:36170615 | DOI:10.5858/arpa.2021-0612-RA

Categories: Literature Watch

A Unique Case of Aggressive Central Giant Cell Granuloma in a 10-Year-Old Boy With 16p13.11 Microdeletion Syndrome

Mon, 2022-09-26 06:00

J Investig Med High Impact Case Rep. 2022 Jan-Dec;10:23247096221123146. doi: 10.1177/23247096221123146.

ABSTRACT

Central giant cell granuloma (CGCG) is a rare disease characterized by sporadic, benign, intraosseous mandibular lesions of unknown etiology. Histologically, these lesions are indistinguishable from brown tumors of hyperparathyroidism and cherubism, and occasionally have been associated with different syndromes raising a question for genetic etiology. The CGCG has varied presentation ranging from nonaggressive and indolent to aggressive, destructive, and recurrent, often posing diagnostic and therapeutic challenges. Herein, we present the first case of a 10-year-old boy with CGCG and 16p13.11 microdeletion syndrome, highlight the diagnostic challenges inherent to this heterogeneous disorder, and discuss the genetics and treatment approaches of these complex lesions.

PMID:36154495 | DOI:10.1177/23247096221123146

Categories: Literature Watch

Single-cell genome sequencing of human neurons identifies somatic point mutation and indel enrichment in regulatory elements

Mon, 2022-09-26 06:00

Nat Genet. 2022 Sep 26. doi: 10.1038/s41588-022-01180-2. Online ahead of print.

ABSTRACT

Accurate somatic mutation detection from single-cell DNA sequencing is challenging due to amplification-related artifacts. To reduce this artifact burden, an improved amplification technique, primary template-directed amplification (PTA), was recently introduced. We analyzed whole-genome sequencing data from 52 PTA-amplified single neurons using SCAN2, a new genotyper we developed to leverage mutation signatures and allele balance in identifying somatic single-nucleotide variants (SNVs) and small insertions and deletions (indels) in PTA data. Our analysis confirms an increase in nonclonal somatic mutation in single neurons with age, but revises the estimated rate of this accumulation to 16 SNVs per year. We also identify artifacts in other amplification methods. Most importantly, we show that somatic indels increase by at least three per year per neuron and are enriched in functional regions of the genome such as enhancers and promoters. Our data suggest that indels in gene-regulatory elements have a considerable effect on genome integrity in human neurons.

PMID:36163278 | DOI:10.1038/s41588-022-01180-2

Categories: Literature Watch

The Benefits of Family Screening in Rare Diseases: Genetic Testing Reveals 165 New Cases of Fabry Disease among At-Risk Family Members of 83 Index Patients

Fri, 2022-09-23 06:00

Genes (Basel). 2022 Sep 9;13(9):1619. doi: 10.3390/genes13091619.

ABSTRACT

BACKGROUND: Fabry disease (FD, OMIM #301500) is a rare, progressive, X-linked, inherited genetic disease caused by a functional deficiency of lysosomal α-galactosidase, leading to the accumulation of glycosphingolipids in virtually all of the body's cell types and fluids. Patients with rare genetic diseases and non-specific symptoms often experience substantial diagnostic delays, which can negatively impact the prompt initiation of treatment. If FD is not treated specifically, end organ damage (such as chronic renal failure, hypertrophic cardiomyopathy with arrhythmia, and strokes) impairs quality of life and reduces life expectancy.

PATIENTS AND METHODS: For 83 consecutive patients with FD referred to the Russian reference center for lysosomal storage diseases, family trees were built and genetic testing (cascade genotyping) was offered to family members.

RESULTS: The pathogenic GLA variant associated with FD was identified for all 83 probands. Family testing using cascade genotyping enabled the identification of 165 additional cases of FD among the tested 331 at-risk family members.

DISCUSSION: This is the first study to have described family screening in a large Russian cohort of patients with FD and chronic kidney disease. Raising awareness of FD among clinicians is important for earlier diagnosis and specific treatment.

PMID:36140787 | PMC:PMC9498688 | DOI:10.3390/genes13091619

Categories: Literature Watch

Newborn screening and the recommended uniform screening panel: Optimal submissions and suggested improvements based on an advocacy organization's decade-long experience

Thu, 2022-09-22 06:00

Am J Med Genet C Semin Med Genet. 2022 Jun;190(2):156-161. doi: 10.1002/ajmg.c.32001. Epub 2022 Sep 22.

ABSTRACT

The National MPS Society, Inc., founded in 1974, is a rare disease advocacy non-profit with a tripartite mission addressing the needs of the mucopolysaccharidosis and mucolipidosis communities through advocacy, research, and family and patient support. The Recommended Uniform Screening Panel (RUSP) of conditions for newborn screening (NBS), legislatively mandated in 2008, was implemented in 2010 by the Secretary of Health and Human Services (HSS), through the adoption of 29 core conditions. Since its inception the RUSP has grown to 35 core conditions. Each addition followed a defined nomination process that has itself undergone further definition over time. Since the adoption of the RUSP, the Society has nominated two conditions that have been approved by the Advisory Committee on Heritable Disorders in Children and Newborns (ACHDNC) and forwarded to the Secretary of HSS for inclusion on the RUSP. This history places the Society in a position to reflect on the process of successfully nominating conditions. Additionally, the Society is well placed by this experience to provide observations on the RUSP process. We will highlight best practices for pending and future nominations and reflect on potential improvements to the process and infrastructure of NBS, the RUSP, and the ACHDNC.

PMID:36135708 | DOI:10.1002/ajmg.c.32001

Categories: Literature Watch

Development and Characterization of Type I, Type II, and Type III LIM-Kinase Chemical Probes

Thu, 2022-09-22 06:00

J Med Chem. 2022 Sep 22. doi: 10.1021/acs.jmedchem.2c01106. Online ahead of print.

ABSTRACT

LIMKs are important regulators of actin and microtubule dynamics, and they play essential roles in many cellular processes. Deregulation of LIMKs has been linked to the development of diverse diseases, including cancers and cognitive disabilities, but well-characterized inhibitors known as chemical probes are still lacking. Here, we report the characterization of three highly selective LIMK1/2 inhibitors covering all canonical binding modes (type I/II/III) and the structure-based design of the type II/III inhibitors. Characterization of these chemical probes revealed a low nanomolar affinity for LIMK1/2, and all inhibitors 1 (LIMKi3; type I), 48 (TH470; type II), and 15 (TH257; type III) showed excellent selectivity in a comprehensive scanMAX kinase selectivity panel. Phosphoproteomics revealed remarkable differences between type I and type II inhibitors compared with the allosteric inhibitor 15. In phenotypic assays such as neurite outgrowth models of fragile X-chromosome, 15 showed promising activity, suggesting the potential application of allosteric LIMK inhibitors treating this orphan disease.

PMID:36136092 | DOI:10.1021/acs.jmedchem.2c01106

Categories: Literature Watch

Rare diseases in the differential diagnosis of myalgia

Mon, 2022-09-19 06:00

Nervenarzt. 2022 Oct;93(10):1062-1073. doi: 10.1007/s00115-022-01393-0.

ABSTRACT

Myalgia describes pain in the skeletal muscles. According to the current German clinical guidelines from 2020 (AWMF register number: 030/051), the initial diagnostic assessment consists of the anamnesis, clinical examination, electrophysiological examination and standard laboratory tests. Additional special examinations, such as molecular genetic investigations, special laboratory tests, medical imaging and muscle biopsy are only needed in certain cases. This article focuses on rare neurological diseases that are classically associated with myalgia. In this context etiologically different diseases are considered, whereby some genetically linked diseases (fascioscapulohumeral dystrophy, FSHD, dystrophia myotonica, McArdle's disease, Pompe's disease, limb girdle muscular dystrophy) are contrasted with diseases with an (auto)immune-related pathogenesis (stiff-person syndrome, Isaacs syndrome). The aspects relevant for the diagnosis are particularly highlighted. The therapeutic aspects of the diseases are not part of this article.

PMID:36121449 | DOI:10.1007/s00115-022-01393-0

Categories: Literature Watch

Characteristics and factors associated with mortality due to rare diseases in Chile, 2002-2017

Mon, 2022-09-19 06:00

Biomedica. 2022 Sep 2;42(3):508-521. doi: 10.7705/biomedica.6281.

ABSTRACT

Introduction: Rare diseases are characterized by their low prevalence, chronically debilitating and life-threatening nature. Objective: To determine the characteristics and factors associated with mortality due to rare diseases in Chile from 2002 to 2017. Materials and methods: We conducted an analytical cross-sectional study based on secondary mortality database from the Departamento de Estadística e Información en Salud (DEIS), Ministerio de Salud de Chile (Department of Statistics and Health Information, Chile Ministry of Health) from 2002 to 2017. The specific mortality rates adjusted by age and sex were calculated. A normality analysis was conducted using the Kolmogorov-Smirnov test. In addition, a chi-square test of independence for associations and multivariate logistic regression was applied to determine the probability of death. Results: Between 2008 and 2012 there were 10,718 deaths due to rare diseases, 53.2% of them occurred among women. The average annual mortality rate was 3.9 per 100,000 inhabitants: 4.1 in women and 3.8 in men. The main causes of mortality among women were Creutzfeldt-Jakob disease, anencephaly and autoinmune hepatitis, and among men, Creutzfeldt-Jakob disease, muscular dystrophy and anencephaly. Women are 1.75 times more likely to die than men (adjusted Odds Ratio (aOR) = 1.75; 95% CI: 1.69 - 1.82). The highest probability of dying occurred among children aged 0-4 years (aOR = 15.30; 95% CI: 14.10 - 19.20). Conclusion: Overall, the burden of mortality due to rare disease was higher among women of all ages in Chile between 2002 and 2017.

PMID:36122290 | DOI:10.7705/biomedica.6281

Categories: Literature Watch

Prognostic model based on m6A-associated lncRNAs in esophageal cancer

Fri, 2022-09-16 06:00

Front Endocrinol (Lausanne). 2022 Aug 30;13:947708. doi: 10.3389/fendo.2022.947708. eCollection 2022.

ABSTRACT

BACKGROUND: This research aimed to build an m6A-associated lncRNA prognostic model of esophageal cancer that can be used to predict outcome in esophageal cancer patients.

METHODS: RNA sequencing transcriptome data and clinical information about patients with esophageal cancer were obtained according to TCGA. Twenty-four m6A-associated genes were selected based on previous studies. m6A-associated lncRNAs were determined through Pearson correlation analysis. Three m6A-associated lncRNA prognostic signatures were built through analysis of the training set using univariate, LASSO, and multivariate Cox regression. To validate the stabilization of the risk signature, Kaplan-Meier and ROC curve analyses were performed on the testing and complete sets. The prognoses of EC patients were predicted quantitatively by building a nomogram. GSEA was conducted to analyze the underlying signaling pathways and biological processes. To identify the underlying mechanisms through which the lncRNAs act, we constructed a PPI network and a ceRNA network and conducted GO and KEGG pathway analyses. EC samples were evaluated using the ESTIMATE algorithm to compute stromal, immune, and estimate scores. The ssGSEA algorithm was used to quantitatively infer immune cell infiltration and immune functions. The TIDE algorithm was performed to simulate immune evasion and predict the response to immunotherapy.

RESULTS: We identified and validated an m6A-associated lncRNA risk model in EC that could correctly and reliably predict the OS of EC patients. The ceRNA network, PPI network, and GO and KEGG pathway analyses confirmed and the underlying mechanisms and functions provided enlightenment regarding therapeutic strategies for EC. Immunotherapy responses were better in the low-risk subgroup, and PD-1 and CTLA4 checkpoint immunotherapy benefited the patients in the low-risk subgroup.

CONCLUSIONS: We constructed a new m6A-related lncRNA prognostic risk model of EC, based on three m6A-related lncRNAs: LINC01612, AC025166.1 and AC016876.2, that can predict the prognoses of EC patients.

PMID:36111294 | PMC:PMC9468245 | DOI:10.3389/fendo.2022.947708

Categories: Literature Watch

Identifying obstacles hindering the conduct of academic-sponsored trials for drug repurposing on rare-diseases: an analysis of six use cases

Thu, 2022-09-15 06:00

Trials. 2022 Sep 15;23(1):783. doi: 10.1186/s13063-022-06713-y.

ABSTRACT

BACKGROUND: Academic-sponsored trials for rare diseases face many challenges; the present paper identifies hurdles in the set-up of six multinational clinical trials for drug repurposing, as use cases.

METHODS: Six academic-sponsored multinational trials aiming to generate knowledge on rare diseases drug repurposing were used as examples to identify problems in their set-up. Coordinating investigators leading these trials provided feedback on hurdles linked to study, country, and site set up, on the basis of pre-identified categories established through the analysis of previous peer-reviewed publications.

RESULTS: Administrative burden and lack of harmonization for trial-site agreements were deemed as a major hurdle. Other main identified obstacles included the following: (1) complexity and restriction on the use of public funding, especially in a multinational set up, (2) drug supply, including procurement tendering rules and country-specific requirements for drug stability, and (3) lack of harmonization on regulatory requirements to get trial approvals.

CONCLUSION: A better knowledge of the non-commercial clinical research landscape and its challenges and requirements is needed to make drugs-especially those with less commercial gain-accessible to rare diseases patients. Better information about existing resources like research infrastructures, clinical research programs, and counseling mechanisms is needed to support and guide clinicians through the many challenges associated to the set-up of academic-sponsored multinational trials.

PMID:36109818 | PMC:PMC9479412 | DOI:10.1186/s13063-022-06713-y

Categories: Literature Watch

Orphan drug development in alpha-1 antitypsin deficiency

Thu, 2022-09-15 06:00

Sci Rep. 2022 Sep 15;12(1):15497. doi: 10.1038/s41598-022-19707-2.

ABSTRACT

Alpha-1 antitrypsin deficiency (AATD, OMIM #613490) is a rare metabolic disorder affecting lungs and liver. The purpose of this study is to assess the impact of the US orphan drug act on AATD by providing a quantitative clinical-regulatory insight into the status of FDA orphan drug approvals and designations for compounds intended to treat AATD. This is across-sectional analysis of the FDA database for orphan drug designations. Primary endpoint: orphan drug approvals. Secondary endpoint: orphan drug designations by the FDA. Close of database was 16 July 2021. STROBE criteria were respected. Primary outcome: one compound, alpha-1-proteinase inhibitor (human) was approved as an orphan drug in 1987 with market exclusivity until 1994. Secondary outcome: sixteen compounds received FDA orphan drug designation including protein, anti-inflammatory, mucolytic, gene, or cell therapy. Drug development activities in AATD were comparable to other rare conditions and led to the FDA-approval of one compound, based on a relatively simple technological platform. The current unmet medical need to be addressed are extrapulmonary manifestations, in this case the AATD-associated liver disease. Orphan drug development is actually focusing on (1) diversified recombinant AAT production platforms, and (2) innovative gene therapies, which may encompass a more holistic therapeutic approach.

PMID:36109566 | PMC:PMC9477815 | DOI:10.1038/s41598-022-19707-2

Categories: Literature Watch

Uterine tumor resembling ovarian sex cord tumor: A rare case report

Thu, 2022-09-15 06:00

Medicine (Baltimore). 2022 Sep 2;101(35):e30414. doi: 10.1097/MD.0000000000030414.

ABSTRACT

RATIONALE: A uterine tumor resembling an ovarian sex cord tumor (UTROSCT) is a clinically rare disease with an unclear origin and biological behavior.

PATIENT CONCERNS: We present a case of UTROSCT in a 42-year-old woman who presented with abnormally increased menstrual volume for 2 years.

DIAGNOSES: Initially, only ultrasound examination was performed to diagnose uterine fibroids, and then the tumor was surgically removed and sent for pathological examination. The patient was ultimately diagnosed with UTROSCT mainly based on pathological immunohistochemical examination and was further diagnosed with low malignant potential for recurrence based on genetic testing.

INTERVENTIONS AND OUTCOMES: The patient underwent hysterectomy and bilateral adnexectomy, and no adjuvant radiotherapy or chemotherapy was performed after the surgery. Follow-up to date has indicated that she is in good condition.

LESSONS: UTROSCT is a rare disease that requires pathological immunohistochemical examination to confirm the diagnosis and genetic testing when necessary so that a clear diagnosis can inform better decision-making regarding treatment measures.

PMID:36107540 | PMC:PMC9439761 | DOI:10.1097/MD.0000000000030414

Categories: Literature Watch

The combination of recurrent otitis media and adenotomy in early childhood as diagnostic marker of mucopolysaccharidosis type II (Hunter syndrome)

Thu, 2022-09-15 06:00

Vestn Otorinolaringol. 2022;87(4):19-22. doi: 10.17116/otorino20228704119.

ABSTRACT

Mucopolysaccharidoses are a group of rare lysosomal accumulation diseases caused by a deficiency of the lysosomal enzyme and the accumulation of mucopolysaccharides in various organs and tissues. Children with mucopolysaccharidosis type II (Hunter syndrome) develop multisystem dysfunction, including severe airway obstruction. At the same time, 34% of patients already at an early age (2-3 years) undergo surgical manipulations related to ENT organs (tonsillectomy, adenotomy). The article describes a clinical case of diagnosis of type II mucopolysaccharidosis by a pediatric otorhinolaryngologist. The main manifestations of the disease are discussed in detail, including the presence of indications for adenotomy at the age of 2 years, episodes of otitis media, which served as diagnostic markers for suspected orphan disease mucopolysaccharidosis type II. The leading role of the pediatric otorhinolaryngologist in the early diagnosis of the rare disease mucopolysaccharidosis type II is substantiated.

PMID:36107175 | DOI:10.17116/otorino20228704119

Categories: Literature Watch

Exome sequencing of 500 Brazilian patients with rare diseases: what we have learned

Wed, 2022-09-14 06:00

Sao Paulo Med J. 2022 Sep-Oct;140(5):734-736. doi: 10.1590/1516-3180.2022.0076.R1.21072022.

NO ABSTRACT

PMID:36102462 | DOI:10.1590/1516-3180.2022.0076.R1.21072022

Categories: Literature Watch

Identifying project topics and requirements in a citizen science project in rare diseases: a participative study

Wed, 2022-09-14 06:00

Orphanet J Rare Dis. 2022 Sep 14;17(1):357. doi: 10.1186/s13023-022-02514-3.

ABSTRACT

BACKGROUND: Due to their low prevalence (< 5 in 10,000), rare diseases are an important area of research, with the active participation of those affected being a key factor. In the Citizen Science project "SelEe" (Researching rare diseases in a citizen science approach), citizens collaborate with researchers using a digital application, developed as part of the project together with those affected, to answer research questions on rare diseases. The aim of this study was to define the rare diseases to be considered, the project topics and the initial requirements for the implementation in a digital application.

METHODS: To address our research questions, we took several steps to engage citizens, especially those affected by rare diseases. This approach included the following methods: pre- and post-survey (questionnaire), two workshops with focus group discussion and a requirements analysis workshop (with user stories).

RESULTS: In the pre-survey, citizens suggested 45 different rare diseases and many different disease groups to be considered in the project. Two main project topics (A) "Patient-guided documentation and data collection" (20 votes) and (B) "Exchange of experience and networking" (13 votes) were identified as priorities in the workshops and ranked in the post-survey. The requirements workshop resulted in ten user stories and six initial requirements to be implemented in the digital application.

CONCLUSION: Qualitative, citizen science research can be used to collectively identify stakeholder needs, project topics and requirements for a digital application in specific areas, such as rare diseases.

PMID:36104743 | DOI:10.1186/s13023-022-02514-3

Categories: Literature Watch

Early-Onset and Severe Complex Hereditary Spastic Paraplegia Caused by De Novo Variants in SPAST

Wed, 2022-09-14 06:00

Mov Disord. 2022 Sep 14. doi: 10.1002/mds.29225. Online ahead of print.

ABSTRACT

BACKGROUND: Familial hereditary spastic paraplegia (HSP)-SPAST (SPG4) typically presents with a pure HSP phenotype.

OBJECTIVE: The aim of this study was to delineate the genotypic and phenotypic spectrum of children with de novo HSP-SPAST.

METHODS: This study used a systematic cross-sectional analysis of clinical and molecular features.

RESULTS: We report the clinical and molecular spectrum of 40 patients with heterozygous pathogenic de novo variants in SPAST (age range: 2.2-27.7 years). We identified 19 unique variants (16/40 carried the same recurrent variant, p.Arg499His). Symptom onset was in early childhood (median: 11.0 months, interquartile range: 6.0 months) with significant motor and speech delay, followed by progressive ascending spasticity, dystonia, neurogenic bladder dysfunction, gastrointestinal dysmotility, and epilepsy. The mean Spastic Paraplegia Rating Scale score was 32.8 ± 9.7 (standard deviation).

CONCLUSIONS: These results confirm that de novo variants in SPAST lead to a severe and complex form of HSP that differs from classic familial pure HSP-SPAST. Clinicians should be aware of this syndrome in the differential diagnosis for cerebral palsy. © 2022 International Parkinson and Movement Disorder Society.

PMID:36103453 | DOI:10.1002/mds.29225

Categories: Literature Watch

Expansion of the clinical and neuroimaging spectrum associated with NDUFS8-related disorder

Wed, 2022-09-14 06:00

JIMD Rep. 2022 Aug 23;63(5):391-399. doi: 10.1002/jmd2.12303. eCollection 2022 Sep.

ABSTRACT

Biallelic pathogenic variants in NDUFS8, a nuclear gene encoding a subunit of mitochondrial complex I, result in a mitochondrial disorder characterized by varying clinical presentations and severity. Here, we expand the neuroimaging and clinical spectrum of NDUFS8-related disorder. We present three cases from two unrelated families (a girl and two brothers) homozygous for a recurrent pathogenic NDUFS8 variant [c.460G>A, p.(Gly154Ser)], located in the [4Fe-4S] domain of the protein. One of the patients developed auto-antibody positive diabetic ketoacidosis. Brain MRIs performed in two of the three patients demonstrated diffuse cerebral and cerebellar white matter involvement including corticospinal tracts, but notably had sparing of deep gray matter structures. Our report expands the neuroimaging phenotype of NDUFS8-related disorder to include progressive leukodystrophy with increasing brainstem and cerebellar involvement, with relative sparing of the basal ganglia. In addition, we describe autoimmune diabetes in association with NDUFS8-related disorder, though the exact mechanism of this association is unclear. This paper provides a comprehensive review of case presentation and progressive neuroimaging findings of three patients from two unrelated families that have an identical pathogenic NDUFS8 variant, which expands the clinical spectrum of NDUFS8-associated neurological disease.

PMID:36101822 | PMC:PMC9458602 | DOI:10.1002/jmd2.12303

Categories: Literature Watch

Novel frameshift mutation in LIS1 gene is a probable cause of lissencephaly: a case report

Tue, 2022-09-13 06:00

BMC Pediatr. 2022 Sep 14;22(1):545. doi: 10.1186/s12887-022-03595-6.

ABSTRACT

BACKGROUND: Lissencephaly (LIS) is a cortical malformation, characterized by smooth or nearly smooth cerebral surface and a shortage of gyral and sulcal development, which is caused by deficient neuronal migration during embryogenesis. Neuronal migration involves many gene products, among which is the product of the PAFAH1B1 gene, associated with this disease. LIS is a rare disease, characterized by low population frequency, and with non-specific clinical symptoms such as early epilepsy, developmental delay or cerebral palsy-like motor problems. Given that high-throughput sequencing techniques have been improving diagnosis, we have chosen this technique for addressing this patient.

CASE PRESENTATION: We present the case of a seven years old male patient with an undiagnosed rare disease, with non-specific clinical symptoms possibly compatible with lissencephaly. The patient was enrolled in a study that included the sequencing of his whole genome. Sequence data was analyzed following a bioinformatic pipeline. The variants obtained were annotated and then subjected to different filters for prioritization. Also mitochondrial genome was analyzed. A novel candidate frameshift insertion in known PAFAH1B1 gene was found, explaining the index case phenotype. The assessment through in silico tools reported that it causes nonsense mediated mechanisms and that it is damaging with high confidence scores. The insertion causes a change in the reading frame, and produces a premature stop codon, severely affecting the protein function and probably the silencing of one allele. The healthy mother did not carry the mutation, and the unaffected father was not available for analysis.

CONCLUSIONS: Through this work we found a novel de novo mutation in LIS1/PAFAH1B1 gene, as a likely cause of a rare disease in a young boy with non-specific clinical symptoms. The mutation found correlates with the phenotype studied since the loss of function in the gene product has already been described in this condition. Since there are no other variants in the PAFAH1B1 gene with low population frequency and due to family history, a de novo disease mechanism is proposed.

PMID:36100855 | DOI:10.1186/s12887-022-03595-6

Categories: Literature Watch

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