Síndrome de Noonan asociado a mutación del gen SOS1, reporte de caso / Noonan syndrome associated with a mutation of the SOS1 gene, case report

Introducción: El síndrome de Noonan es un trastorno genético de herencia autosómica dominante con una expresión fenotípica variable. Se encuentra dentro de las enfermedades conocidas como rasopatías, producidas por las mutaciones en los genes RAS. Los pacientes se caracterizan por dismorfismo facial, talla baja, enfermedad cardíaca congénita, alteraciones músculos esqueléticas y en algunos casos discapacidad intelectual. Caso clínico: En el presente reporte se describe el caso de un paciente masculino de un mes de edad que acude a consulta externa, presentando dismorfismo facial y estenosis pulmonar, por lo que se realiza un seguimiento multidisciplinario por sospecha de Síndrome de Noonan. A partir del cuarto mes desarrolló linfedema en la zona del deltoides. Evolución: A los 7 meses de vida se realiza secuenciación de exoma, encontrando una variante patogénica en el gen SOS1, confirmando el diagnóstico de dicho síndrome. Conclusión: Este caso documenta la presencia de síndrome de Noonan con mutación del gen SOS1 con dismorfología facial típica, estenosis de la válvula pulmonar, criptorquidia y displasia linfática con linfedema del deltoides, hallazgo no descrito en casos previos.

Introduction: Noonan syndrome is a dominant autosomal inherited ge-netic disorder with variable phenotypic expression. It is found within diseases known as rasopathies and is pro-duced by mutations in RAS genes. Patients are character-ized by facial dysmorphism, short stature, congenital heart disease, musculoskeletal disorders, and, in some cases, intellectual disability. Clinical case: This report describes the case of a one-month-old male patient who comes to the outpatient clinic, presenting with facial dysmorphism and pulmonary steno-sis, for which a multidisciplinary follow-up is carried out due to suspicion of Noonan syndrome. From the fourth month, the patient developed lymphedema in the deltoid area. Evolution: At 7 months of age, exome sequencing was per-formed, finding a pathogenic vari-ant in the SOS1 gene and confirming the diagnosis of this syndrome. Conclusion: This case documents the presence of Noonan syndrome with a mutation of the SOS1 gene with typical facial dysmorphology, pulmonary valve stenosis, cryptor-chidism and lymphatic dysplasia with deltoid.

15q Duplication Syndrome: Report on the First Patient from Ecuador with an Unusual Clinical Presentation.

BACKGROUND: The 15q11.1-13.1 duplication, also known as Dup15q syndrome, is a rare congenital disease affecting 1 in 30,000 to 1 in 60,000 children worldwide. This condition is characterized by the presence of at least one extra copy of genetical material within the Prader-Willi/Angelman Critical Region (PWACR) of the referred 15q11.2-q13.1 chromosome. Case Report. Our study presents the clinical and genetical features of the first patient with a denovo 15q11.2 interstitial duplication on the maternal allele (inv Dup15q) that mimics a milder Prader-Willi syndrome probably due to an atypical disruption of the SNHG14 gene. Methylation-specific MLPA analysis has confirmed the presence of a very unlikely duplication that lies between breakpoint 1 (BP1) and the middle of BP2 and BP3 (BP3). This atypical alteration might be linked to the milder patient's clinical phenotype. CONCLUSIONS: This is the first Dup15q patient reported in Ecuador and of the very few in South America. This aberration has never been described in a patient with Dup15q, and the unusual clinical presentation is probably due to the atypical distal breakpoint occurring within the gene SNHG14 which lies between BP2 and BP3 and does not therefore contain the whole PWACR. If the duplication disrupted the gene, then it is possible that it is the cause of, or contributing to, the patient's clinical phenotype.

Clinical, genetic and microbiological characterization of pediatric patients with cystic fibrosis in a public Hospital in Ecuador.

BACKGROUND: To carry out a complete clinical, pathological, genetic and microbiological characterization of pediatric patients with molecular confirmed cystic fibrosis (CF) attending the Carlos Andrade Marín Hospital (HCAM) within the study period. METHODS: A cross-sectional analysis of the pediatric population with a confirmed diagnosis of CF disease who attended HCAM, one of the largest tertiary-level hospitals in Ecuador, between 2017 and 2018 was performed. All demographic, clinical and genetic variables were obtained from the electronic medical records (EMR) stored by the hospital. RESULTS: Forty seven patients with CF were included in the study. Gender distribution was similar between male (48.9%, n = 23) and female patients (51.1%, n = 24). The Tiffeneau-Pinelli index (FEV1/FVC) changed significantly after nine months post-diagnosis (85.55 ± 13.26; p < 0.05). The most common pathogenic genetic variants were F508del, found in 52.78% of the cohort (n = 19); H609R, found in 36.11% (n = 13); g.204099A > C, found in 14.1% (n = 7), followed by G85E and the N1303K with 11.11% (n = 3) each. CONCLUSIONS: To our best knowledge, this is the first study exploring the clinical, genetic and bacteriological profile of CF's patients in Ecuador. Within the cohort of patients, an important and unique genetic feature was characterized by the presence of the g.204099A > C and the c.206359C > A homozygous polymorphism as well as the presence of the H609R variant, a mutation only reported among Ecuadorians.

Disfunción Mioneural Periférica Como Único Elemento Para El Diagnostico De La Distrofia Miotónica Tipo I / Myoneural Disfunction For The Diagnosis Of Myotonic Dystrophy Type I

Resumen La distrofia miotónica tipo 1, también conocida como enfermedad de Steinert, es un trastorno mulsistémico que afecta principalmente al sistema músculo esquelético y liso, así como al ojo, corazón, sistema endócrino y sistema nervioso central. Esta patología es infrecuente y se caracteriza por miotonía generalizada y daño multiorgánico. Su expresión clínica es variable, pero en la mayoría de los casos se presenta un grado variable de debilidad muscular, arritmias cardiacas y otros trastornos de la conducción, alteraciones endócrinas, trastornos del sueño, cataratas y calvicie. Esta es una enfermedad hereditaria con tres fenotipos reconocibles: leve, clásico y congénito. Dependiendo de su presentación puede tener mal pronóstico y una progresión usualmente rápida, la misma que carece de un tratamiento efectivo. Presentación del caso: Paciente femenina de 54 años que ingresa al Servicio de Traumatología del Hospital San Vicente de Paul de Ibarra, Ecuador por presentar una fractura de fémur izquierdo resultante de una caída desde su silla de ruedas. Durante la hospitalización la paciente presenta insuficiencia respiratoria tipo II sin causa aparente por lo cual es ingresada a UCI para soporte ventilatorio. La paciente presenta dificultad para lograr el destete ventilatorio debido a la debilidad muscular distal y proximal. La electromiografía revela un patrón miopático compatible con el diagnóstico de distrofia miotónica tipo I. Se realiza traqueotomía y es dada de alta para seguimiento por el servicio de Medicina Interna. Se sugiere la realización de estudio molecular diagnóstico. Conclusiones: El estudio molecular es la opción diagnóstica indicada para determinar con certeza la presencia de la distrofia miotónica tipo I, además de permitir determinar su severidad dependiendo del número de repetidos. Sin embargo, las limitaciones de recursos en el presente caso forzaron a que se busquen evidencias para el diagnóstico a través de la electromiografía. Hasta le alta, el tratamiento sigue siendo sintomático. Debido a que su modo de herencia es autosómico dominante, por expansión de trinucléotidos, se debe buscar familiares que pueden encontrarse asintomáticos y podrían tener esta patología.

Abstract Myotonic dystrophy type 1, also known as Steinert's disease, is a mulsystemic disorder that primarily affects the skeletal and smooth muscle, as well as the eye, heart, endocrine system and central nervous system. This pathology is uncommon and is characterized by generalized myotonia and multiorgan damage. Its clinical expression is variable, but in most cases, there is a variable degree of muscle weakness, cardiac arrhythmias and other conduction disorders, endocrine disorders, sleep disorders, cataracts and baldness. This is a hereditary disease with three recognizable phenotypes: mild, classic and congenital. Depending on the presentation, it may show poor prognosis and a usually rapid progression, which lacks of effective treatment. Case presentation: 54-year-old female patient who enters the Traumatology service of San Vicente de Paul Hospital in Ibarra, Ecuador for presenting a left femur fracture resulting from a fall of her own height. During hospitalization, the patient presented with type II respiratory failure without apparent cause, so she was admitted to the ICU for ventilatory support. The patient had difficulty achieving ventilatory weaning due to distal and proximal muscle weakness. Electromyography reveals a myopathic pattern compatible with the diagnosis of myotonic dystrophy type I. A tracheotomy was performed, and she was discharged for follow-up by the Internal Medicine service. The performance of a molecular diagnostic study was suggested. Conclusions: The molecular study is the diagnostic gold standard to determine with certainty the presence of myotonic dystrophy type I, besides allowing to determine its severity depending on the number of repeated. However, resource limitations in the present case forced evidence to be sought for diagnosis through electromyography. The treatment remains symptomatic. Because of its inheritance pattern being autosomal dominant, due to the expansion of trinucleotides, family members must be evaluated because they may have the diagnosis even though asymptomatic.