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Hereditary breast cancer is most commonly attributed to germline BRCA1 and BRCA2 gene variants. The vast majority of BRCA1 and BRCA2 mutation carriers are single heterozygotes, and double heterozygosity (DH) is a very rare finding. Here, we describe the case of a BRCA1/BRCA2 double heterozygous female proband diagnosed with breast cancer. Genetic testing for hereditary breast and ovarian cancer revealed two pathogenic variants in the BRCA1 (c.5095C>T, p.(Arg1699Trp)) and in BRCA2 genes (c.658_659delGT, p.(Val220Ilefs*4)) in heterozygous form. None of the variants were founder Jewish mutations; to our knowledge, these rare deleterious variants have not been previously described in DH patients in the literature. The patient had triple-negative unilateral breast cancer at the age of 36 and 44 years. Based on family studies, the BRCA1 variant was maternally inherited.
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Neoplasias de la Mama , Neoplasias Ováricas , Neoplasias de la Mama Triple Negativas , Humanos , Femenino , Adulto , Genes BRCA2 , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Hungría , Predisposición Genética a la Enfermedad , Linaje , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama Triple Negativas/genética , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Mutación de Línea GerminalRESUMEN
Wilms' tumor (WT) is the most common renal malignancy in children. In diffuse hyperplastic perilobar nephroblastomatosis (DHPLN), nephrogenic rests result in a bulky enlargement of the kidney, a condition considered as a premalignant state before WT. Despite relevant clinical differences between WT and DHPLN, they are often challenging to distinguish based on histology. Molecular markers would improve differential diagnosis, but none are available at present. In our study, we investigated the potential of microRNAs (miRNAs) as such biomarkers, also aiming to shed light on the chronological order of expression changes. Formalin-fixed, paraffin-embedded (FFPE) samples from four DHPLN cases and adjacent healthy tissues were tested using a PCR array containing primers for 84 miRNAs implicated in genitourinary cancer. Expression in DHPLN was compared to WT data available in dbDEMC. Let-7, miR-135, miR-146a-5p, miR-182-5p, miR-183-5p, miR-20b-3p, miR-29b-3p, miR-195-5p and miR-17-5p showed potential to be used as biomarkers to distinguish WT and DHPLN in cases when traditional differential diagnosis is inconclusive. Our study also revealed miRNAs which may play a role in the initial steps of the pathogenesis (at a precancerous stage) and ones which become deregulated later in WT. More experiments are needed to confirm our observations and find new candidate markers.
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Neoplasias Renales , MicroARNs , Tumor de Wilms , Niño , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Diagnóstico Diferencial , Tumor de Wilms/diagnóstico , Tumor de Wilms/genética , Neoplasias Renales/diagnóstico , Neoplasias Renales/genética , Neoplasias Renales/metabolismo , Riñón/metabolismo , Hiperplasia/patologíaRESUMEN
Duchenne muscular dystrophy (DMD) is the most common inherited muscle dystrophy. Patients are characterized by muscle weakness, gross motor delay, and elevated serum creatinine kinase (CK) levels. The disease is caused by mutations in the DMD gene located on the X chromosome. Due to the X-linked recessive inheritance pattern, DMD most commonly affects males, who are generally diagnosed between the age of 3-5 years. Here we present an ultra-rare manifestation of DMD in a female patient. Cytogenetic examination showed that she has a t(X;10)(p21.1;p12.1) translocation, which turned out to affect the DMD gene with one of the breakpoints located in exon 54 (detected by genome sequencing). The X-inactivation test revealed skewed X-inactivation (ratio 99:1). Muscle histology and dystrophin immunohistochemistry showed severe dystrophic changes and highly reduced dystrophin expression, respectively. These results, in accordance with the clinical picture and a highly elevated serum CK, led to the diagnosis of DMD. In conclusion, although in very rare cases, DMD can manifest in female patients as well. In this case, a balanced X-autosome reciprocal translocation disrupts the DMD gene and skewed X-inactivation leads to the manifestation of the DMD phenotype.
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Distrofina , Distrofia Muscular de Duchenne , Masculino , Femenino , Humanos , Distrofina/genética , Distrofia Muscular de Duchenne/diagnóstico , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/patología , Inactivación del Cromosoma X , Cromosoma X , MutaciónRESUMEN
Cerebral calcification may be caused by several potentially treatable conditions, however, in most cases it does not receive special attention in clinical practice. From the point of view of etiology, the diseases associated with cerebral calcification can be divided into two main groups: idiopathic (mostly incurable) and secondary (potentially treatable). The first group includes mainly the hereditary diseases identified before 2021 (primary familial brain calcification subtypes, previously known as Fahr's disease or Fahr's syndrome). In contrast, the second group includes diseases with cerebral calcification that develop generally as a consequence of metabolic/endocrine/autoimmune abnormalities. The aim of our research was to present hereditary and non-hereditary etiologies associated with extensive brain calcification. We compare the detailed clinical, radiological and laboratory results of 6 patients with prominent cerebral calcification identified in our clinic in the last 3 years (idiopathic and secondary etiologies as well). Our research draws attention to the complexity of the etiologies in the context of cerebral calcification. We recommend, beside NGS-based sequence analyses, the application of array comparative genomic hybridization as well, to identify potential genetic etiologies associated with brain calcification.
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Enfermedades de los Ganglios Basales , Calcinosis , Enfermedades Neurodegenerativas , Encéfalo/diagnóstico por imagen , Calcinosis/complicaciones , Calcinosis/diagnóstico por imagen , Calcinosis/genética , Hibridación Genómica Comparativa , HumanosRESUMEN
Early detection, characterization and monitoring of cancer are possible by using extracellular vesicles (EVs) isolated from non-invasively obtained liquid biopsy samples. They play a role in intercellular communication contributing to cell growth, differentiation and survival, thereby affecting the formation of tumor microenvironments and causing metastases. EVs were discovered more than seventy years ago. They have been tested recently as tools of drug delivery to treat cancer. Here we give a brief review on extracellular vesicles, exosomes, microvesicles and apoptotic bodies. Exosomes play an important role by carrying extracellular nucleic acids (DNA, RNA) in cell-to-cell communication causing tumor and metastasis development. We discuss the role of extracellular vesicles in the pathogenesis of cancer and their practical application in the early diagnosis, follow up, and next-generation treatment of cancer patients.
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Exosomas/genética , Exosomas/metabolismo , Neoplasias/patología , Biomarcadores de Tumor , Comunicación Celular , Progresión de la Enfermedad , Detección Precoz del Cáncer , Exosomas/patología , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Medicina de Precisión , Microambiente TumoralRESUMEN
Imaging nano-objects in complex systems such as nanocomposites using time-of-flight secondary ion mass spectrometry (TOF-SIMS) is a challenging task. Due to a very small amount of the material and a matrix effect, the number of generated secondary ions can be insufficient to represent a 3D elemental distribution despite being detected in a mass spectrum. Therefore, a model sample consisting of a ZrCuAg matrix with embedded Al nanoparticles is designed. A high mass difference between the light Al and heavy matrix components limits mass interference. The chemical structure measurements using a pulsed 60 keV Bi32+ beam or a continuous 30 keV Ga+ beam reveals distinct Al signal segregation. This can indicate a spatially resolved detection of single 10s of nanometer large particles and/or their agglomerates for the first time. However, TOF-SIMS images of 50 nm or smaller objects do not necessarily represent their exact size and shape but can rather be their convolutions with the primary ion beam shape. Therefore, the size of nanoparticles (25-64 nm) was measured using scanning transmission electron microscopy. Our studies prove the capability of TOF-SIMS to image chemical structure of nanohybrids which is expected to help building new functional materials and optimize their properties.
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Gonadal dysgenesis (GD) is a rare cause of differences of sex development (DSD) with highly variable clinical and genetic conditions. Although identification of the causative genetic alterations can offer a clearer prognosis and personalized management to patients, more than 50% of the DSD cases still do not have an accurate genetic diagnosis. NR5A1 (previously known as SF-1), is a transcriptional regulator of genes required for normal development and functional maintenance of the gonads and the adrenal glands. Nucleotide sequence variants of the NR5A1 gene have been reported in numerous patients with GD with or without adrenal failure, however, microdeletion or partial deletion in the NR5A1 gene have been described only in a few GD cases. In this case study, we present a subject with female phenotype, mild clitoromegaly, partial GD and normal adrenal function. Cytogenetic analysis revealed a 46,XY SRY + karyotype. Microarray analysis did not identify pathogenic copy number variations, nor did panel sequencing of the most common DSD genes. Subsequently, multiplex ligation-dependent probe amplification (MLPA) was performed to test for small deletion/duplication of the most frequently affected genes associated with GD. Using this method, we have identified a novel heterozygous deletion involving exons 5 and 6 of the NR5A1 gene as the cause of abnormal sexual development of the patient. This report expands our knowledge about the range and pathogenetic role of NR5A1 mutations associated with partial gonadal dysgenesis in 46,XY DSD. Furthermore, our data emphasises the indispensable role of MLPA in the diagnosis of DSD with unclear etiology.
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Trastorno del Desarrollo Sexual 46,XY/genética , Reacción en Cadena de la Polimerasa Multiplex/métodos , Factor Esteroidogénico 1/genética , Testículo/anomalías , Variaciones en el Número de Copia de ADN/genética , Trastorno del Desarrollo Sexual 46,XY/diagnóstico , Trastornos del Desarrollo Sexual/genética , Exones/genética , Femenino , Heterocigoto , Humanos , Mutación/genética , Eliminación de Secuencia/genética , Desarrollo Sexual/genéticaRESUMEN
BACKGROUND: We have previously reported quantitative exposure-response relationships between physical exposures recorded by technical methods, and complaints and diagnoses in the neck/shoulders, and the elbows/hands, based on group data. In the present study the number of workers was doubled, and information on individual factors, and psychosocial working conditions was used. Relationships between various kinds of exposure and response have been analysed in this larger and more detailed sample. METHODS: The prevalence of complaints (Nordic Questionnaire) and diagnoses (clinical examination) were recorded in a number of occupational groups within which the participants had similar work tasks, 34 groups of female employees (N = 4733 women) and 17 groups of male employees (N = 1107 men). Age and other individual characteristics were recorded, as well as psychosocial work environment factors (job-content questionnaire) for most participants. Postures and velocities (inclinometry) of the head (N = 505) and right upper arm (N = 510), right wrist postures and velocities (electrogoniometry; N = 685), and muscular activity (electromyography; EMG) in the right trapezius muscle (N = 647) and forearm extensors (N = 396) were recorded in representative sub-groups. Exposure-response relationships between physical exposure and musculoskeletal disorders, adjusted for individual factors with Poisson regression were then calculated. The effect of introducing psychosocial conditions into the models was also assessed. RESULTS: Associations were found between head velocity, trapezius activity, upper arm velocity, forearm extensor activity and wrist posture and velocity, and most neck/shoulder and elbow/hand complaints and diagnoses. Adjustment for age, other individual characteristics and psychosocial work conditions had only a limited effect on these associations. For example, the attributable fraction for tension neck syndrome among female workers with the highest quintile of trapezius activity was 58%, for carpal tunnel syndrome versus wrist velocity it was 92% in men in the highest exposure quintile. CONCLUSIONS: Based on the findings, we propose threshold limit values for upper arm and wrist velocity.
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Enfermedades Musculoesqueléticas/etiología , Enfermedades Profesionales/etiología , Exposición Profesional/efectos adversos , Lugar de Trabajo/estadística & datos numéricos , Adulto , Artrometría Articular , Estudios de Cohortes , Electromiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Musculoesqueléticas/diagnóstico , Enfermedades Musculoesqueléticas/epidemiología , Enfermedades Musculoesqueléticas/psicología , Cuello , Enfermedades Profesionales/diagnóstico , Enfermedades Profesionales/epidemiología , Enfermedades Profesionales/psicología , Prevalencia , Rango del Movimiento Articular , Encuestas y Cuestionarios/estadística & datos numéricos , Extremidad Superior , Lugar de Trabajo/psicologíaRESUMEN
BACKGROUND AND PURPOSE: Acute mortality rate of stroke in Hungary is significantly higher than in Western Europe, which is likely to be partially attributable to suboptimal treatment. METHODS: We examined the use of acute vascular imaging and mechanical thrombectomy for acute ischaemic stroke patients. We collected data on 20 consecutive patients from Hungarian stroke centers before 31st August 2016. RESULTS: Out of the reported 410 patients, 166 (40.4%) underwent CT angiography and 44 (10.7%) had mechanical thrombectomy. CONCLUSION: Only about 1/3 of acute ischaemic stroke patients eligible for thrombectomy actually had it. The underlying reasons include long onset-to-door time, low utilization of acute vessel imaging and a limited neuro-intervention capacity needing improvement.
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Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/cirugía , Angiografía por Tomografía Computarizada/métodos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/cirugía , Trombectomía/métodos , Humanos , Hungría , Resultado del TratamientoRESUMEN
BACKGROUND: Current technologies in next-generation sequencing are offering high throughput reads at low costs, but still suffer from various sequencing errors. Although pyro- and ion semiconductor sequencing both have the advantage of delivering long and high quality reads, problems might occur when sequencing homopolymer-containing regions, since the repeating identical bases are going to incorporate during the same synthesis cycle, which leads to uncertainty in base calling. The aim of this study was to evaluate the analytical performance of a pyrosequencing-based next-generation sequencing system in detecting homopolymer sequences using homopolymer-preintegrated plasmid constructs and human DNA samples originating from patients with cystic fibrosis. RESULTS: In the plasmid system average correct genotyping was 95.8% in 4-mers, 87.4% in 5-mers and 72.1% in 6-mers. Despite the experienced low genotyping accuracy in 5- and 6-mers, it was possible to generate amplicons with more than a 90% adequate detection rate in every homopolymer tract. When homopolymers in the CFTR gene were sequenced average accuracy was 89.3%, but varied in a wide range (52.2 - 99.1%). In all but one case, an optimal amplicon-sequencing primer combination could be identified. In that single case (7A tract in exon 14 (c.2046_2052)), none of the tested primer sets produced the required analytical performance. CONCLUSIONS: Our results show that pyrosequencing is the most reliable in case of 4-mers and as homopolymer length gradually increases, accuracy deteriorates. With careful primer selection, the NGS system was able to correctly genotype all but one of the homopolymers in the CFTR gene. In conclusion, we configured a plasmid test system that can be used to assess genotyping accuracy of NGS devices and developed an accurate NGS assay for the molecular diagnosis of CF using self-designed primers for amplification and sequencing.
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Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Fibrosis Quística/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Análisis de Secuencia de ADN/métodos , Secuencias Repetidas en Tándem , Humanos , PlásmidosRESUMEN
BACKGROUND: Autosomal recessive polycystic kidney disease (ARPKD) is genetically one of the least heterogeneous ciliopathies, resulting primarily from mutations of PKHD1. Nevertheless, 13-20% of patients diagnosed with ARPKD are found not to carry PKHD1 mutations by sequencing. Here, we assess whether PKHD1 copy number variations or second locus mutations explain these cases. METHODS: Thirty-six unrelated patients with the clinical diagnosis of ARPKD were screened for PKHD1 point mutations and copy number variations. Patients without biallelic mutations were re-evaluated and screened for second locus mutations targeted by the phenotype, followed, if negative, by clinical exome sequencing. RESULTS: Twenty-eight patients (78%) carried PKHD1 point mutations, three of whom on only one allele. Two of the three patients harbored in trans either a duplication of exons 33-35 or a large deletion involving exons 1-55. All eight patients without PKHD1 mutations (22%) harbored mutations in other genes (PKD1 (n = 2), HNF1B (n = 3), NPHP1, TMEM67, PKD1/TSC2). Perinatal respiratory failure, a kidney length > +4SD and early-onset hypertension increase the likelihood of PKHD1-associated ARPKD. A patient compound heterozygous for a second and a last exon truncating PKHD1 mutation (p.Gly4013Alafs*25) presented with a moderate phenotype, indicating that fibrocystin is partially functional in the absence of its C-terminal 62 amino acids. CONCLUSIONS: We found all ARPKD cases without PKHD1 point mutations to be phenocopies, and none to be explained by biallelic PKHD1 copy number variations. Screening for copy number variations is recommended in patients with a heterozygous point mutation.
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Variaciones en el Número de Copia de ADN , Heterocigoto , Fenotipo , Riñón Poliquístico Autosómico Recesivo/genética , Receptores de Superficie Celular/genética , Adolescente , Alelos , Niño , Preescolar , Análisis Mutacional de ADN , Exones/genética , Femenino , Pruebas Genéticas , Humanos , Lactante , Recién Nacido , Masculino , Mutación Puntual , Riñón Poliquístico Autosómico Recesivo/diagnóstico , Índice de Severidad de la EnfermedadRESUMEN
OBJECTIVE: Fetal samples obtained by invasive techniques are prone to maternal cell contamination (MCC), which may lead to false genotyping results. Our aim was to determine 3 molecular genetic tests' sensitivity to MCC. METHOD: By mixing experiments, 1%, 5%, 10%, 20%, 30%, and 40% MCC was simulated, and significant MCC levels were determined for Sanger DNA sequencing, multiplex ligation-dependent probe amplification (MLPA), and pyrosequencing, a next-generation sequencing method. RESULTS: For Sanger sequencing, the limit of sensitivity to MCC was 5% to 30%. For MLPA, a higher proportion of MCC (≥40%) was shown to lead to diagnostic uncertainty. In contrast, pyrosequencing proved to be very sensitive to MCC, detecting a proportion as low as 1%. CONCLUSION: In the case of Sanger sequencing, sensitivity to MCC was variable, while for MLPA, only high levels of MCC proved to be significant. Although the next-generation sequencing method was sensitive to low-level MCC, if MCC level is determined in parallel, accurate quantification of allelic ratios can help to interpret the diagnostic results. Knowledge of significant MCC levels allows correct prenatal diagnosis even if samples are not purely of fetal origin and repeated sampling can be avoided in many of the cases.
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Contaminación de ADN , Feto/citología , Pruebas Genéticas/métodos , Diagnóstico Prenatal/métodos , Análisis de Secuencia de ADN/métodos , Errores Diagnósticos/prevención & control , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Técnicas de Amplificación de Ácido Nucleico , Embarazo , Sensibilidad y EspecificidadRESUMEN
Smith-Lemli-Opitz syndrome is a recessive disorder caused by mutations in 7-dehydrocholesterol reductase (DHCR)7 with a heterozygous (HET) carrier frequency of 1-3%. A defective DHCR7 causes accumulation of 7-dehydrocholesterol (DHC), which is a highly oxidizable and toxic compound. Recent studies suggest that several antipsychotics, including the highly prescribed pharmaceuticals, aripiprazole (ARI) and trazodone (TRZ), increase 7-DHC levels in vitro and in humans. Our investigation was designed to compare the effects of ARI and TRZ on cholesterol (Chol) synthesis in fibroblasts from DHCR7+/- human carriers and controls (CTRs). Six matched pairs of fibroblasts were treated and their sterol profile analyzed by LC-MS. Significantly, upon treatment with ARI and TRZ, the total accumulation of 7-DHC was higher in DHCR7-HET cells than in CTR fibroblasts. The same set of experiments was repeated in the presence of 13C-lanosterol to determine residual Chol synthesis, revealing that ARI and TRZ strongly inhibit de novo Chol biosynthesis. The results suggest that DHCR7 carriers have increased vulnerability to both ARI and TRZ exposure compared with CTRs. Thus, the 1-3% of the population who are DHCR7 carriers may be more likely to sustain deleterious health consequences on exposure to compounds like ARI and TRZ that increase levels of 7-DHC, especially during brain development.
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Aripiprazol/farmacología , Inhibidores Enzimáticos/farmacología , Mutación , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/genética , Trazodona/farmacología , Adulto , Colesterol/biosíntesis , Femenino , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/antagonistas & inhibidores , Síndrome de Smith-Lemli-Opitz/enzimología , Síndrome de Smith-Lemli-Opitz/genéticaAsunto(s)
Diabetes Mellitus Tipo 1 , Enfermedades Genéticas Ligadas al Cromosoma X , Enfermedades del Sistema Inmune , Síndrome Nefrótico , Niño , Diarrea , Femenino , Factores de Transcripción Forkhead/genética , Humanos , Masculino , Mutación , Síndrome Nefrótico/diagnóstico , Síndrome Nefrótico/etiología , Linfocitos T ReguladoresRESUMEN
Cerebrotendinous xanthomatosis (CTX) is a rare, genetically determined error of metabolism. The characteristic clinical symptoms are diarrhea, juvenile cataracts, tendon xanthomas and neuropsychiatric alterations. The aim of this study is to present a pair of identical adult twins with considerable differences in the severity of phenotype. With regards to neuropsychiatric symptoms, the predominant features were severe Parkinsonism and moderate cognitive dysfunctions in the more-affected individual, whereas these alterations in the less-affected patient were only very mild and mild, respectively. The characteristic increase in the concentrations of serum cholestanol and the lesion volumes in dentate nuclei in the brain assessed with magnetic resonance imaging were quite similar in both cases. The lifestyle conditions, including eating habits of the twin pair, were quite similar as well; therefore, currently unknown genetic modifiers or certain epigenetic factors may be responsible for the differences in severity of phenotype. This case series serves as the first description of an identical twin pair with CTX presenting heterogeneous clinical features.
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Gemelos Monocigóticos , Xantomatosis Cerebrotendinosa/fisiopatología , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Fenotipo , Xantomatosis Cerebrotendinosa/diagnóstico por imagen , Xantomatosis Cerebrotendinosa/patologíaRESUMEN
The classification of diabetes mellitus in adolescents and young adults is often difficult. The diagnosis of the monogenic form of diabetes may have substantial influence on quality of life, prognosis and the choice of the appropriate treatment of affected patients. Among MODY (maturity-onset of diabetes in the young) MODY-1 is rarely detected, only 13 families were described in 2000, and 103 different mutations in 173 families were known in 2013 worldwide. The authors present the first Hungarian case of a monogenic form of diabetes due to HNF4α mutation (MODY-1). The diabetes of the index patient No. 1 (42-year-old woman with insulin treated diabetes) was diagnosed as gestational diabetes at age of 20 when she was treated with diet only. Later, insulin treatment has been initiated when marked hyperglycaemia was detected during an episode of acute pneumonia at age of 26. The diabetes of the index patient No. 2 (20-year-old daughter of the index patient No. 1, treated also with insulin) was diagnosed as type 2 diabetes at age of 13 and the patient was treated with diet only. Later the classification was modified to type 1 and insulin therapy was initiated at age of 14. The manifestation of diabetes, the familial occurrence and the low dose insulin requirement were suggestive for monogenic diabetes. Using molecular genetic method a mutation (c.869G>A, p.R290H) of HNF4α gene was found and MODY-1 was diagnosed in both cases. Insulin therapy was switched to treatment with low dose sulfanylurea and an excellent glycaemic control was achieved and sustained at follow-up of 1-year. No further positive cases were found during screening of other family members.
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Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/genética , Factor Nuclear 4 del Hepatocito/genética , Mutación , Adulto , Femenino , Humanos , Hungría , Hiperglucemia/tratamiento farmacológico , Hiperglucemia/etiología , Hipoglucemiantes/administración & dosificación , Insulina/administración & dosificación , Madres , Núcleo Familiar , LinajeRESUMEN
Introduction - Transthyretin familial amyloid polyneuropathy is a rare autosomal dominant progressive systemic disesase of adults caused by endoneural amyloid deposition due to point mutations of the transthyretin gene. It is the most severe form among hereditary polyneuropathies, being fatal within 10 years if left untreated. The disease is underdiagnosed, the late onset forms (above the age of 50) being probably more widespread than previously thought. Early diagnosis is essential as the early introduction of causal therapy (tafamidis) slows progression and prolongs survival. Patients - We report here three non-related Hungarian cases of transthyretin familial amyloid polyneuropathy with non-Val30Met mutations (His88Arg in two cases, Phe33Leu in one case). They were all characterized by late-onset, progressive, length-dependent, axonal, sensorimotor polyneuropathy and the simultaneous presentation of severe restrictive cardiomyopathy. In all three cases, clinical and electrophysiological signs of myopathy were also present, suggesting the involvement of skeletal muscles as well. In two cases, high resolution ultrasound of the peripheral nerves was also performed, which showed segmental structural alterations (change or loss of fascicular structure) and some increase of echogenicity of the interfascicular epineurium, without substantial enlargement of the nerves. Conclusion - In Hungary, mainly the rare, non-Val30Met mutation forms of transthyretin familial amyloid polyneuropathy are encountered, as in our cases. As opposed to the Val30Met forms, these mutations are characterized by late onset and simultaneous presentation of severe cardiomyopathy. Our report highlights the importance of considering transthyretin familial amyloid polyneuropathy in the differential diagnosis of late-onset, progressive, axonal polyneuropathies of unknown etiology, particularly if associated with cardiac disease.
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Neuropatías Amiloides Familiares/genética , Prealbúmina/genética , Femenino , Humanos , Hungría , Masculino , Persona de Mediana Edad , Mutación PuntualRESUMEN
PURPOSE: NEUROD1 is a tissue-specific basic helix loop helix (bHLH) protein involved in the development and maintenance of the endocrine pancreas and neuronal elements. Loss of NEUROD1 causes ataxia, cerebellar hypoplasia, sensorineural deafness, and severe retinal dystrophy in mice. Heterozygous loss-of-function mutations in NEUROD1 have previously been described as a cause of maturity-onset diabetes of the young (MODY) and late-onset diabetes. To date, homozygous loss-of-function NEUROD1 mutations have only been detected in two patients. Both mutations caused permanent neonatal diabetes and severe neurologic defects, including visual impairment. However, a detailed ophthalmological phenotype of this novel syndrome has not yet been reported. Our aim was to characterize the ophthalmological phenotype associated with the previously reported homozygous c.427_428CT mutation in the NEUROD1 gene. METHODS: The female patient was investigated on multiple occasions between 2009 (age 14) and 2014 (age 19), including visual acuity testing, automated perimetry, funduscopy, anterior-segment imaging, optical coherence tomography of the posterior pole, standard full-field electroretinography, and fundus-autofluorescence imaging. RESULTS: The patient had nyctalopia, blurry vision, and visual field constriction from early childhood. Her best corrected visual acuity ranged between 20/25 and 15/25 during the investigation period. Perimetry showed concentric constriction of the visual field, sparing only the central 30 degrees in both eyes. The anterior segment did not show any morphological changes. Optical coherence tomography revealed total absence of the photoreceptor layer of the retina outside the fovea, where a discoid remnant of cone photoreceptors could be detected. Neither setting of the standard full-field electroretinography could detect any electrical response from the retina. Color fundus photos presented peripheral chorioretinal atrophy and central RPE mottling. A hyperreflective parafoveal ring was detected on fundus autofluorescent photos, a characteristic sign of hereditary retinal dystrophies. CONCLUSIONS: To the best of our knowledge, this is the first report on the ophthalmological phenotype associating with a homozygous NEUROD1 null mutation in humans. Our results indicate that the loss of NEUROD1 has similar functional and anatomic consequences in the human retina as those described in mice. The present description can help the diagnosis of future cases and provide clues on the rate of disease progression.