Andersen-Tawil Syndrome with High Risk of Sudden Cardiac Death in Four Mexican Patients. Cardiac and Extra-Cardiac Phenotypes

ABSTRACT Background: Andersen-Tawil syndrome (ATS) is a cardiac channelopathy that is inherited in an autosomal dominant way, and it is characterized by a triad of periodic paralysis, ventricular arrhythmias, and includes some dysmorphic features with incomplete penetrance and variable expression that result in a challenging diagnosis. Objective: The objective of the study was to describe the cardiac and extra-cardiac phenotype in a cohort of patients with ATS at risk of sudden cardiac death (SCD) to improve its early clinical identification. Methods: In an observational, transversal study, with a deviant case sampling, four female patients with ATS at high risk of SCD were included in the study. They carried the heterozygous pathogenic variants c.407C>T [p.Ser136Phe], c.652C>T [p.Arg218Trp] (n=2), and c.431G>C [p.Gly144Ala] in the KCNJ2 gene. Patients were evaluated by a cardiologist, a clinical geneticist, and a physiatrist. Results: One patient had the classical facial phenotype and the other three had subtle manifestations. The group of patients presented a diverse set of clinical data such as: triangular face, broad forehead, broadening of medial eyebrows, auricular pits, low-set ears, eyelid ptosis, thin lips, mandibular hypoplasia, and diverse types of dental alterations, single transverse palmar crease, camptodactyly, and syndactyly. Long-exercise test showed a decrement in the percentage amplitude up to 44%, classifying patients in IV or V types according to Fournier’s scale. Conclusions: Extra-cardiac manifestations were a common finding in this series of ATS type1 at high risk of SCD. Its recognition could help the clinician in the early identification of patients with ATS, especially for the cardiologist since they are commonly referred only for evaluation of ventricular arrhythmias.

Dysferlin quantification in monocytes for rapid screening for dysferlinopathies.

INTRODUCTION: In this study, we determined normal levels of dysferlin expression in CD14+ monocytes by flow cytometry (FC) as a screening tool for dysferlinopathies. METHODS: Monocytes from 183 healthy individuals and 29 patients were immunolabeled, run on an FACScalibur flow cytometer, and analyzed by FlowJo software. RESULTS: The relative quantity of dysferlin was expressed as mean fluorescence intensity (MFI). Performance of this diagnostic test was assessed by calculating likelihood ratios at different MFI cut-off points, which allowed definition of 4 disease classification groups in a simplified algorithm. CONCLUSION: The MFI value may differentiate patients with dysferlinopathy from healthy individuals; it may be a useful marker for screening purposes. Muscle Nerve 54: 1064-1071, 2016.

[Diagnosis and treatment with steroids for patients with Duchenne muscular dystrophy: experience and recommendations for Mexico. Administración del Patrimonio de la Beneficencia Pública. Asociación de Distrofia Muscular de Occidente]. / Diagnóstico y tratamiento con esteroides de pacientes con distrofia muscular de Duchenne: experiencia y recomendaciones para México.

Duchenne muscular dystrophy is a severe, debilitating and progressive disease that affects 1 in 3,500 live male births in the world. The diagnosis should be confirmed by genetic testing to identify the mutation in the DMD gene or muscle biopsy and immunostaining to demonstrate the absence of dystrophin. Although up to now continues to be an incurable disease, this does not mean it has no treatment. Treatment should be multidisciplinary, looking for the functionality of the patient and avoiding or correcting complications, mainly cardio-respiratory and skeletal. Many proposals have been evaluated and implemented with the aim of improving the quality of life for these patients. The long-term steroids have shown significant benefits, such as prolonging ambulation, reduce the need for spinal surgery, improve cardiorespiratory function and increase survival and the quality of life. This document presents the recommendations based on the experience of the working group and experts worldwide on the diagnosis and treatment with steroids for patients with Duchenne muscular dystrophy.

TITLE: Diagnostico y tratamiento con esteroides de pacientes con distrofia muscular de Duchenne: experiencia y recomendaciones para Mexico.La distrofia muscular de Duchenne es una enfermedad grave, incapacitante y progresiva que afecta a 1 de cada 3.500 recien nacidos varones alrededor del mundo. El diagnostico debera confirmarse mediante pruebas geneticas para identificar la mutacion en el gen DMD, o bien por biopsia muscular e inmunotincion para demostrar la ausencia de distrofina. Aunque actualmente continua siendo una enfermedad incurable, no significa que no tenga tratamiento. Este debe ser multidisciplinario, buscando la funcionalidad del paciente y evitando o corrigiendo las complicaciones, principalmente cardiorrespiratorias y esqueleticas. Se han evaluado e implementado multiples propuestas con la finalidad de mejorar la calidad de vida en estos pacientes. Los esteroides a largo plazo han demostrado importantes beneficios para los pacientes, prolongan la deambulacion, reducen la necesidad de cirugia de columna, mejoran la funcion cardiorrespiratoria, y aumentan la supervivencia y la calidad de vida. En este documento se presentan las recomendaciones con base en la experiencia del grupo de trabajo y de los expertos de ambito mundial sobre el diagnostico y el tratamiento con esteroides para los pacientes con distrofia muscular de Duchenne.