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Síndrome del Cromosoma X Frágil , Paraplejía Espástica Hereditaria , Humanos , Paraplejía Espástica Hereditaria/diagnóstico , Paraplejía Espástica Hereditaria/genética , Síndrome del Cromosoma X Frágil/genética , Expansión de Repetición de Trinucleótido , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genéticaRESUMEN
We report on the successful treatment of a severe, recalcitrant dermatitis caused by CTLA-4 insufficiency with dupilumab, raising the possibility of a role of type 2 immunity in clinical conditions associated with CTLA-4 insufficiency.
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Early diagnosis of genetic rare diseases is an unmet need in Brazil, where an estimated 10-13 million people live with these conditions. Increased use of chromosome microarray assays, exome sequencing, and whole genome sequencing as first-tier testing techniques in suitable indications can shorten the diagnostic odyssey, eliminate unnecessary tests, procedures, and treatments, and lower healthcare expenditures. A selected panel of Brazilian experts in fields related to rare diseases was provided with a series of relevant questions to address before a multi-day conference. Within this conference, each narrative was discussed and edited through numerous rounds of discussion until agreement was achieved. The widespread adoption of exome sequencing and whole genome sequencing in Brazil is limited by various factors: cost and lack of funding, reimbursement, awareness and education, specialist shortages, and policy issues. To reduce the burden of rare diseases and increase early diagnosis, the Brazilian healthcare authorities/government must address the barriers to equitable access to early diagnostic methods for these conditions. Recommendations are provided, including broadening approved testing indications, increasing awareness and education efforts, increasing specialist training opportunities, and ensuring sufficient funding for genetic testing.
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Pruebas Genéticas , Enfermedades Raras , Humanos , Secuenciación del Exoma , Brasil , Enfermedades Raras/diagnóstico , Enfermedades Raras/genética , Secuenciación Completa del GenomaRESUMEN
Rare diseases (RDs) cause considerable death and disability in Latin America. Still, there is no consensus on their definition across the region. Patients with RDs face a diagnostic odyssey to find a correct diagnosis, which may last many years and creates a burden for caregivers, healthcare systems, and society. These diagnostic delays have repercussions on the health and economic burden created by RDs and continue to represent an unmet medical need. This review analyzes barriers to the widespread adoption of newborn screening (NBS) programs and early diagnostic methods for RDs in Latin America and provides recommendations to achieve this critical objective. Increasing the adoption of NBS programs and promoting early diagnosis of RDs are the first steps to improving health outcomes for patients living with RDs. A coordinated, multistakeholder effort from leaders of patient organizations, government, industry, medical societies, academia, and healthcare services is required to increase the adoption of NBS programs. Patients' best interests should remain the guiding principle for decisions regarding NBS implementation and early diagnosis for RDs.
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Gain-of-function mutations in the STAT1 gene have been initially associated with chronic mucocutaneous candidiasis. However, further research has shown that STAT1 GOF variants may increase susceptibility to infection by other intracellular pathogens. This report describes the first case of disseminated leishmaniasis associated with a STAT1 GOF mutation in a pediatric patient who did not have chronic mucocutaneous candidiasis. The patient was a four-year-old boy presenting with fever, severe asthenia, hepatosplenomegaly, pancytopenia, and liver failure. Bone marrow aspirate revealed hemophagocytosis and Leishmania parasites. Treatment consisted primarily of liposomal amphotericin B, as per the Hemophagocytic Lymphohistiocytosis 2004 protocol. After eight weeks of treatment, the patient did not improve and was submitted to diagnostic splenectomy. Activated macrophages and nodular spleen necrosis secondary to the visceral leishmaniasis were detected. Unfortunately, the patient died in the second week after splenectomy due to overwhelming systemic infection. DNA sequencing revealed a pathogenic (p. R274Q) GOF mutation in STAT1.
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Candidiasis Mucocutánea Crónica , Leishmaniasis Visceral , Candidiasis Mucocutánea Crónica/complicaciones , Candidiasis Mucocutánea Crónica/genética , Niño , Preescolar , Mutación con Ganancia de Función , Humanos , Leishmaniasis Visceral/complicaciones , Leishmaniasis Visceral/diagnóstico , Leishmaniasis Visceral/genética , Masculino , Mutación , Factor de Transcripción STAT1/genéticaRESUMEN
OBJECTIVE: The Bacille Calmette-Guérin (BCG) vaccine is routinely applied in Brazil. Adverse events (AE) may occur in patients with inborn or acquired immunodeficiencies, varying between local (BCGitis) or disseminated (BCGosis) reactions. We evaluated 53 individuals with local or disseminated adverse events to BCG vaccination to assess if they had inborn errors of immunity (IEI). METHODS: Patients diagnosed with an adverse event following BCG vaccination between 2014 and 2017 were included in the study. We collected clinical data, immunophenotyped T and B lymphocytes, and natural killer cells (NK), assessed oxidative function of neutrophils through dihydrorhodamine (DHR) 123 testing, and genotyped 361 genes related to IEI through targeted (panel) sequencing. RESULTS: The median age of the 53 individuals was four months (IQ 1.5-12), and 52.8% were male. Forty-eight (90.6%) individuals presented only locoregional AE and five (9.4%) presented both locoregional and disseminated AE. Nine (16.9%) patients were diagnosed with an IEI. Four of them presented BCGitis and five presented BCGosis after BCG vaccination. Clinically, four presented chronic granulomatous disease (CGD), three Mendelian susceptibility to mycobacterial disease (MSMD), and two severe combined immunodeficiency (SCID). Patients with IEI had a higher frequency of systemic symptomatology (p = 0.002), history of other infections (p < 0.001), parental consanguinity (p = 0.01), familial history of sick siblings (p < 0.001), or early deaths in the family (p < 0.01). CONCLUSION: There is a high frequency of IEI in patients with locoregional and disseminated adverse events to BCG vaccination, revealing the need for the investigation of IEI accompanied by clinical and familial inquiry.
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Vacuna BCG , Inmunodeficiencia Combinada Grave , Tuberculosis , Preescolar , Femenino , Humanos , Masculino , Vacuna BCG/efectos adversos , Brasil/epidemiología , Inmunodeficiencia Combinada Grave/genética , Tuberculosis/diagnóstico , Vacunación/efectos adversosRESUMEN
Rare diseases affect up to 13.2 million individuals in Brazil. The Brazilian Rare Genomes Project is envisioned to further the implementation of genomic medicine into the Brazilian public healthcare system. Here we report the validation results of a whole genome sequencing (WGS) procedure for implementation in clinical laboratories. In addition, we report data quality for the first 1,200 real-world patients sequenced. We sequenced a well-characterized group of 76 samples, including seven gold standard genomes, using a PCR-free WGS protocol on Illumina Novaseq 6,000 equipment. We compared the observed variant calls with their expected calls, observing good concordance for single nucleotide variants (SNVs; mean F-measure = 99.82%) and indels (mean F-measure = 99.57%). Copy number variants and structural variants events detection performances were as expected (F-measures 96.6% and 90.3%, respectively). Our WGS protocol presented excellent intra-assay reproducibility (coefficients of variation ranging between 0.03% and 0.20%) and inter-assay reproducibility (coefficients of variation ranging between 0.02% and 0.09%). Limitations of the WGS protocol include the inability to confidently detect variants such as uniparental disomy, balanced translocations, repeat expansion variants, and low-level mosaicism. In summary, the observed performance of the WGS protocol was in accordance with that seen in the best centers worldwide. The Rare Genomes Project is an important initiative to bring pivotal improvements to the quality of life of the affected individuals.
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Hereditary cancer risk syndromes are caused by germline variants, commonly in tumor suppressor genes. Most studies on hereditary cancer have been conducted in white populations. We report the largest study in Brazilian individuals with multiple ethnicities. We genotyped 1682 individuals from all country regions with Next-generation sequencing (NGS) panels. Most were women with a personal/family history of cancer, mostly breast and ovarian. We identified 321 pathogenic/likely pathogenic (P/LP) variants in 305 people (18.1%) distributed among 32 genes. Most were on BRCA1 and BRCA2 (129 patients, 26.2% and 14.3% of all P/LP, respectively), MUTYH (42 monoallelic patients, 13.1%), PALB2 (25, 7.8%), Lynch syndrome genes (17, 5.3%), and TP53 (17, 5.3%). Transheterozygosity prevalence in our sample was 0.89% (15/1682). BRCA1/BRCA2 double heterozygosity rate was 0.78% (1/129) for BRCA variants carriers and 0.06% (1/1682) overall. We evaluated the performance of the genetic testing criteria by NCCN and the Brazilian National Health Agency (ANS). The inclusion criteria currently used in Brazil fail to identify 17%-25% of carriers of P/LP variants in hereditary cancer genes. Our results add knowledge on the Brazilian spectrum of cancer risk germline variants, demonstrate that large multigene panels have high positivity rates, and indicate that Brazilian inclusion criteria for genetic testing should be improved.
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Neoplasias de la Mama , Síndromes Neoplásicos Hereditarios , Proteína BRCA1/genética , Proteína BRCA2/genética , Brasil , Neoplasias de la Mama/genética , Femenino , Genes BRCA2 , Predisposición Genética a la Enfermedad , Pruebas Genéticas/métodos , Mutación de Línea Germinal , Humanos , Masculino , Síndromes Neoplásicos Hereditarios/genéticaRESUMEN
ABSTRACT Gain-of-function mutations in the STAT1 gene have been initially associated with chronic mucocutaneous candidiasis. However, further research has shown that STAT1 GOF variants may increase susceptibility to infection by other intracellular pathogens. This report describes the first case of disseminated leishmaniasis associated with a STAT1 GOF mutation in a pediatric patient who did not have chronic mucocutaneous candidiasis. The patient was a four-year-old boy presenting with fever, severe asthenia, hepatosplenomegaly, pancytopenia, and liver failure. Bone marrow aspirate revealed hemophagocytosis and Leishmania parasites. Treatment consisted primarily of liposomal amphotericin B, as per the Hemophagocytic Lymphohistiocytosis 2004 protocol. After eight weeks of treatment, the patient did not improve and was submitted to diagnostic splenectomy. Activated macrophages and nodular spleen necrosis secondary to the visceral leishmaniasis were detected. Unfortunately, the patient died in the second week after splenectomy due to overwhelming systemic infection. DNA sequencing revealed a pathogenic (p. R274Q) GOF mutation in STAT1.
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Inborn errors of immunity (IEI), which were previously termed primary immunodeficiency diseases, represent a large and growing heterogeneous group of diseases that are mostly monogenic. In addition to increased susceptibility to infections, other clinical phenotypes have recently been associated with IEI, such as autoimmune disorders, severe allergies, autoinflammatory disorders, benign lymphoproliferative diseases, and malignant manifestations. The IUIS 2019 classification comprises 430 distinct defects that, although rare individually, represent a group affecting a significant number of patients, with an overall prevalence of 1:1,200-2,000 in the general population. Early IEI diagnosis is critical for appropriate therapy and genetic counseling, however, this process is deeply dependent on accurate laboratory tests. Despite the striking importance of laboratory data for clinical immunologists, several IEI-relevant immunoassays still lack standardization, including standardized protocols, reference materials, and external quality assessment programs. Moreover, well-established reference values mostly remain to be determined, especially for early ages, when the most severe conditions manifest and diagnosis is critical for patient survival. In this article, we intend to approach the issue of standardization and quality control of the nonfunctional diagnostic tests used for IEI, focusing on those frequently utilized in clinical practice. Herein, we will focus on discussing the issues of nonfunctional immunoassays (flow cytometry, enzyme-linked immunosorbent assays, and turbidimetry/nephelometry, among others), as defined by the pure quantification of proteins or cell subsets without cell activation or cell culture-based methods.
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Técnicas de Laboratorio Clínico/normas , Inmunoensayo/normas , Enfermedades de Inmunodeficiencia Primaria/diagnóstico , Técnicas de Cultivo de Célula , Diagnóstico Precoz , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Humanos , Nefelometría y Turbidimetría , Garantía de la Calidad de Atención de Salud , Estándares de ReferenciaAsunto(s)
Ataxia/congénito , Cerebelo/anomalías , Trastornos Neurológicos de la Marcha/congénito , Receptores de Inositol 1,4,5-Trifosfato/genética , Malformaciones del Sistema Nervioso/genética , Discapacidades del Desarrollo/genética , Marcha/genética , Humanos , Masculino , Ilustración Médica , Persona de Mediana Edad , Mutación , SíndromeRESUMEN
Cryopyrin-associated periodic syndromes (CAPS) are a group of autoinflammatory diseases associated with NLRP3 gain of function mutations. CAPS associated mutations are found predominantly in exon 3. The objective of this study is to describe a new variant on NRLP3 gene and its phenotype. Case report description of a new NRLP3 pathogenic variant and literature case-based search through INFEVERS database. A 21-year old male who presented multiple tonic-clonic seizures on his 3rd day of life. At age 2, he had recurrent central facial palsy, high fever (40 °C), painful and persistent oral ulcers, abdominal pain, nausea and vomiting, and delayed neuropsychomotor development, with polyarthritis in wrists and knees. Over the years, several symptoms were observed: livedo reticularis, Raynaud's phenomenon, positive pathergy test, heat allodynia, extremely painful genital ulcers, and sporadic conjunctivitis. Laboratory studies revealed persistently elevated inflammatory markers and serum amyloid protein A (30 µg/l). The genetic panel for autoinflammatory diseases revealed heterozygous mutation in the NLRP3, (c.2068G > C, p.E690Q) with 0% of frequency in the general population. The patient denies rash and did not have frontal bossing or patellar overgrowth. We found a positive familial history on mother and brother, who carried the same mutation. The patient was started on canakinumab which controlled his symptoms. Currently, 241 missense variants in the NLRP3 have been described. We presented a new mutation in exon 3 of the NRLP3 gene in a patient that fulfills clinical criteria for CAPS who had complete clinical response to Canakinumab, supporting the idea that this mutation is pathogenic.
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Síndromes Periódicos Asociados a Criopirina/genética , Proteína con Dominio Pirina 3 de la Familia NLR , Anticuerpos Monoclonales Humanizados/uso terapéutico , Síndromes Periódicos Asociados a Criopirina/diagnóstico , Síndromes Periódicos Asociados a Criopirina/tratamiento farmacológico , Diagnóstico Diferencial , Exones , Humanos , Masculino , Mutación , Fenotipo , Adulto JovenRESUMEN
The aim of this work consists in the use of cashew gum (Anacardium occidentale), a naturally occurring tropical specie from the Brazilian northeastern coast, for the synthesis of CoFe2O4 (CF) and NiFe2O4 (NF) nanoparticles. The structural, morphological and vibrational properties of nanoparticles were characterized by analytical and spectroscopic techniques such as X-ray diffraction (XRD), FTIR, Raman spectroscopy, TEM, SAED and TG. Magnetic properties were investigated through Mössbauer spectroscopy and DC magnetometry. The XRD results showed single phase nanoparticles with space group Fd-3m and crystallite size of 7.4 and 6.0 for CF and NF, respectively. TEM images showed agglomerated particles with mode sizes of 5.0 and 6.5 nm for CF and NF. SAED confirmed the crystalline spinel structure. The TGA and FTIR showed the presence of a carbonaceous material in the samples. FTIR and Raman spectroscopy demonstrated vibrational modes characteristic of metaloxygen bonds in the tetrahedral and octahedral sites. Magnetization measurements showed that both samples are superparamagnetic at 300 K. The Mössbauer spectra at 90 K showed the presence of single-phase CF and NF.
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Anacardium/química , Cobalto/química , Geles/química , Nanoestructuras/química , Níquel/química , Gomas de Plantas/química , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Termogravimetría , Difracción de Rayos XRESUMEN
Mutations in the FAS gene are the most common cause of Autoimmune Lymphoproliferative Syndrome (ALPS), and the majority of them affect the intracellular domain of FAS protein, particularly the region termed death domain. However, approximately one third of these mutations affect the extracellular region of FAS and most are stop codons, with very few missense changes having been described to date. We previously described 7 patients with a FAS missense extracellular mutation, C107Y, two in homozygozity and 5 in heterozygosity. We investigated here the mechanistic effects of this mutation and observed that the homozygous patients did not show any FAS surface expression, while the heterozygous patients had diminished receptor expression. Aiming to understand why a missense mutation was abolishing receptor expression, we analyzed intracellular FAS protein trafficking using fluorescent fusion proteins of wild type FAS, two missense extracellular mutants (FAS-C107Y and FAS-C104Y) and one missense change localized in the intracellular region, FAS-D260E. The FAS-C107Y and FAS-C104Y mutants failed to reach the cell surface, being retained at the endoplasmic reticulum, unlike the WT or the FAS-D260E which were clearly expressed at the plasma membrane. These results support haploinsufficiency as the underlying mechanism involved in the pathogenesis of ALPS caused by extracellular FAS missense mutations.
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Síndrome Linfoproliferativo Autoinmune/genética , Mutación Missense/genética , Estructura Terciaria de Proteína/genética , Proteínas Recombinantes de Fusión/genética , Receptor fas/metabolismo , Alelos , Apoptosis/genética , Argentina , Espacio Extracelular , Células HEK293 , Haploinsuficiencia , Humanos , Linaje , Ingeniería de Proteínas , Transporte de Proteínas/genética , Receptor fas/genéticaRESUMEN
Patients with mutations of the recombination-activating genes (RAG) present with diverse clinical phenotypes, including severe combined immune deficiency (SCID), autoimmunity, and inflammation. However, the incidence and extent of immune dysregulation in RAG-dependent immunodeficiency have not been studied in detail. Here, we have demonstrated that patients with hypomorphic RAG mutations, especially those with delayed-onset combined immune deficiency and granulomatous/autoimmune manifestations (CID-G/AI), produce a broad spectrum of autoantibodies. Neutralizing anti-IFN-α or anti-IFN-ω antibodies were present at detectable levels in patients with CID-G/AI who had a history of severe viral infections. As this autoantibody profile is not observed in a wide range of other primary immunodeficiencies, we hypothesized that recurrent or chronic viral infections may precipitate or aggravate immune dysregulation in RAG-deficient hosts. We repeatedly challenged Rag1S723C/S723C mice, which serve as a model of leaky SCID, with agonists of the virus-recognizing receptors TLR3/MDA5, TLR7/-8, and TLR9 and found that this treatment elicits autoantibody production. Altogether, our data demonstrate that immune dysregulation is an integral aspect of RAG-associated immunodeficiency and indicate that environmental triggers may modulate the phenotypic expression of autoimmune manifestations.
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Autoanticuerpos/inmunología , Autoantígenos/inmunología , Enfermedades Autoinmunes/inmunología , Citocinas/inmunología , Proteínas de Unión al ADN/deficiencia , Enfermedad Granulomatosa Crónica/inmunología , Proteínas de Homeodominio/inmunología , Proteínas Nucleares/deficiencia , Inmunodeficiencia Combinada Grave/inmunología , Adolescente , Adulto , Animales , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Especificidad de Anticuerpos , Autoanticuerpos/sangre , Enfermedades Autoinmunes/genética , Niño , Preescolar , ARN Helicasas DEAD-box/inmunología , Proteínas de Unión al ADN/genética , Modelos Animales de Enfermedad , Femenino , Enfermedad Granulomatosa Crónica/genética , Enfermedad Granulomatosa Crónica/terapia , Proteínas de Homeodominio/genética , Humanos , Lactante , Helicasa Inducida por Interferón IFIH1 , Masculino , Ratones , Ratones Endogámicos , Proteínas Nucleares/genética , Inmunodeficiencia Combinada Grave/genética , Inmunodeficiencia Combinada Grave/terapia , Receptores Toll-Like/agonistas , Receptores Toll-Like/inmunología , Virosis/inmunología , Adulto JovenRESUMEN
Desmoglein-2 (DSG2), a member of the desmosomal cadherin superfamily, has been linked to arrhythmogenic right ventricular cardiomyopathy (ARVC)which may cause life-threatening ventricular arrhythmias and sudden death. Fatal arrhythmias resulting in sudden death also occur in the absence of morphologic cardiac abnormalities at autopsy. We sequenced all 15 exons of DSG2 in DNA extracted from post-mortem heart tissues of 25 patients dying with ARVC and 25 from sudden unexplained death (SUD). The primers were designed using the Primer Express 3.0 software. Direct sequencing for both sense and antisense strands was performed with a BigDye Terminator DNA sequencing kit on a 3130 xl Genetic Analyzer. Mutation damage prediction was made using Mutation Taster, Polyphen and SIFT software. 2 DSG2 mutations (p. S1026Q fsX12, p. G678R)in two ARVC samples and 2 DSG2 mutations(p. E 896K, p. A858 V) in two SUD samples were identified, all the mutations were novel. We concluded that DSG2 mutations may not specific for ARVC and may be related to the fatal arrhythmic events even in patients with a morphological normal heart.
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Displasia Ventricular Derecha Arritmogénica/genética , Muerte Súbita/etiología , Desmogleína 2/genética , Mutación , Adolescente , Exones , Femenino , Genética Forense , Ventrículos Cardíacos/patología , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Adulto JovenRESUMEN
BACKGROUND: Gliomas account for more than 60 % of all primary central nervous system neoplasms. Low-grade gliomas display a tendency to progress to more malignant phenotypes and the most frequent and malignant gliomas are glioblastomas (GBM). Another type of glioma, oligodendroglioma originates from oligodendrocytes and glial precursor cells and represents 2-5 % of gliomas. The discrimination between these two types of glioma is actually controversial, thus, a molecular distinction is necessary for better diagnosis. METHODS: iTRAQ-based quantitative proteomic analysis was performed on non-neoplastic brain tissue, on astrocytoma grade II, glioblastoma with short and long survival and oligodendrogliomas. RESULTS: We found that expression of nucleophosmin (NPM1), glucose regulated protein 78 kDa (GRP78), nucleolin (NCL) and heat shock protein 90 kDa (HSP90B1) were increased, Raf kinase inhibitor protein (RKIP/PEBP1) was decreased in glioblastoma and they were associated with a network related to tumor progression. Expression level of heat shock protein 27 (HSPB1/HSP27) discriminated glioblastoma presenting short (6 ± 4 months, n = 4) and long survival (43 ± 15 months, n = 4) (p = 0.00045). Expression level of RNA binding protein nova 1 (NOVA1) differentiated low-grade oligodendroglioma and astrocytoma grade II (p = 0.0082). Validation were done by Western blot, qRT-PCR and immunohistochemistry in a larger casuistry. CONCLUSION: Taken together, our quantitative proteomic analysis detected the molecular triad, NPM1, GRP78 and RKIP participating together with NCL and HSP27/HSPB1 in a network related to tumor progression. Additionally, two new important targets were uncovered: NOVA1 useful for diagnostic refinement differentiating astrocytoma from oligodendroglioma, and HSPB1/HSP27, as a predictive factor of poor prognosis for GBM.
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Biomarcadores de Tumor/análisis , Glioblastoma/metabolismo , Proteínas de Choque Térmico HSP27/análisis , Oligodendroglioma/metabolismo , Proteoma/análisis , Proteínas de Unión al ARN/análisis , Adulto , Anciano , Biomarcadores de Tumor/metabolismo , Encéfalo/metabolismo , Encéfalo/patología , Chaperón BiP del Retículo Endoplásmico , Glioblastoma/mortalidad , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas de Choque Térmico , Humanos , Marcaje Isotópico , Persona de Mediana Edad , Chaperonas Moleculares , Antígeno Ventral Neuro-Oncológico , Nucleofosmina , Oligodendroglioma/mortalidad , Valor Predictivo de las Pruebas , Proteoma/metabolismo , Proteómica , Proteínas de Unión al ARN/metabolismo , Análisis de Supervivencia , Adulto JovenRESUMEN
Ras-associated autoimmune leukoproliferative disorder (RALD) is a chronic, nonmalignant condition that presents with persistent monocytosis and is often associated with leukocytosis, lymphoproliferation, and autoimmune phenomena. RALD has clinical and laboratory features that overlap with those of juvenile myelomonocytic leukemia (JMML) and chronic myelomonocytic leukemia (CMML), including identical somatic mutations in KRAS or NRAS genes noted in peripheral blood mononuclear cells. Long-term follow-up of these patients suggests that RALD has an indolent clinical course whereas JMML is fatal if left untreated. Immunophenotyping peripheral blood from RALD patients shows characteristic circulating activated monocytes and polyclonal CD10(+) B cells. Distinguishing RALD from JMML and CMML has implications for clinical care and prognosis.