Targeted massively parallel sequencing for congenital generalized lipodystrophy

ABSTRACT Objective: Our aim is to establish genetic diagnosis of congenital generalized lipodystrophy (CGL) using targeted massively parallel sequencing (MPS), also known as next-generation sequencing (NGS). Subjects and methods: Nine unrelated individuals with a clinical diagnosis of CGL were recruited. We used a customized panel to capture genes related to genetic lipodystrophies. DNA libraries were generated, sequenced using the Illumina MiSeq, and bioinformatics analysis was performed. Results: An accurate genetic diagnosis was stated for all nine patients. Four had pathogenic variants in AGPAT2 and three in BSCL2. Three large homozygous deletions in AGPAT2 were identified by copy-number variant analysis. Conclusions: Although we have found allelic variants in only 2 genes related to CGL, the panel was able to identify different variants including deletions that would have been missed by Sanger sequencing. We believe that MPS is a valuable tool for the genetic diagnosis of multi-genes related diseases, including CGL.

Aggressive papillary thyroid carcinoma in a child with type 2 congenital generalized lipodystrophy

SUMMARY Thyroid carcinoma (TC) is rare in children, particularly in those aged < 10 years. Several studies have demonstrated a correlation between neoplasms and hyperinsulinemia and insulin resistance, which are often associated with a higher risk for and/or aggressiveness of the neoplasm. Congenital generalized lipodystrophy (CGL) with autosomal recessive inheritance is a rare disease and is characterized by the lack of adipose tissue, severe insulin resistance, and early metabolic disturbances. Here, we reported a rare case of a type 2 CGL in a girl who presented with a papillary TC (PTC) at the age of 7 years. She had no family history of TC or previous exposure to ionizing radiation. She had a generalized lack of subcutaneous fat, including the palmar and plantar regions, muscle hypertrophy, intense acanthosis nigricans, hepatomegaly, hypertriglyceridemia, severe insulin resistance, and hypoleptinemia. A genetic analysis revealed a mutation in the BSCL2 gene (p.Thr109Asnfs* 5). Ultrasound revealed a hypoechoic solid nodule measuring 1.8 × 1.0 × 1.0 cm, and fine needle aspiration biopsy suggested malignancy. Total thyroidectomy was performed, and a histopathological examination confirmed PTC with vascular invasion and parathyroid lymph node metastasis (pT3N1Mx stage). This is the first report to describe a case of differentiated TC in a child with CGL. Severe insulin resistance that is generally observed in patients with CGL early in life, especially in those with type 2 CGL, may be associated with this uncommon presentation of aggressive PTC during childhood.

Síndrome Berardinelli / Berardinelli syndrome

El síndrome Berardinelli es una enfermedad poco frecuente, con amplia heterogeneidad clínica y genética, clínicamente caracterizada por pérdida de tejido adiposo a nivel subcutáneo y de otros tejidos. Esta lipodistrofia generalizada congénita provoca hipertrofia muscular, asociada a trastornos endocrinos, con crecimiento acelerado durante la infancia, pubertad precoz e hiperglicemia. Está considerada una enfermedad metabólica rara, que se hereda de forma autosómico recesiva. En la actualidad se describen 4 variantes de este síndrome, con varios genes implicados. El objetivo de este trabajo es describir las características clínicas en una niña, en la cual su aspecto fenotípico recuerda este síndrome, por la lipodistrofia marcada y aumento de la musculatura desde la etapa de lactante, por lo cual se consideró necesaria la valoración en equipo multidisciplinario para su adecuado seguimiento y asesoramiento genético a sus familiares(AU)

Berardinelli syndrome is a rare disease, with broad clinical and genetic heterogeneity, and clinically characterized by loss of fatty tissue at subcutaneous level and of other tissues. This generalized congenital lipodystrophy causes muscle hypertrophy associated to endocrine disorders, accelerated growth at childhood, early puberty and hyperglycemia. It is considered as a rare metabolic disease and also recessive autosomal inheritance. Nowadays, four variants of the syndrome are described in which several gens are involved. The objective of this paper was to describe the clinical characteristics of a girl whose phenotypical aspect resembles this syndrome due to the marked lipodystrophy and increased musculature since her breastfeeding phase. Therefore, it was necessary to make an assessment by a multidisciplinary team for her adequate follow-up and the genetic counselling to her family(AU)

Lipodistrofia congénita generalizada en un paciente con anomalía de Dandy Walker / Congenital generalized lipodystrophy in pacient with Dandy Walker anomaly

La asociación entre la lipodistrofia congénita generalizada y la anomalía de Dandy Walker no es habitual. Se reporta el caso de una niña de 1 año de edad que ingresa al hospital a los 4 meses por riesgo social, con diagnóstico de anomalía de Dandy Walker. Durante su internación, se evidencia en forma progresiva aspecto acromegaloide, facies triangular, hirsutismo, lipoatrofia, hipertrofia muscular, clitoromegalia, distensión abdominal con hepatomegalia progresiva e hpertrigliceridernia. Se arriba así al diagnóstico clínico de lipodistrofia congénita generalizada. Se revisan los aspectos clínicos y el seguimiento interdisciplinario para la detección oportuna de insulinorresistencia y diabetes, pubertad precoz, miocardiopatía, entre otras. Respecto de la anomalía de Dandy Walker, se realizan controles evolutivos en búsqueda de la aparición de signos de hipertensión endocraneana. Por el carácter autosómico recesivo de la lipodistrofia congénita generalizada, es importante realizar el asesoramiento genético a los padres.

The objective of this study is to describe the unexpected association between the congenital generalized lipodystrophy (CGL) and Dandy Walker anomaly. We report the case of a 1-year-old infant who was hospitalized at her fourth month of life with Dandy Walker anomaly diagnosis and an increased social risk. During her hospitalization, she developed progressively: acromegaloid aspect, triangular fascia, hirsutism, lipoatrophy, muscle hypertrophy, clitoromegaly, abdominal distention, progressive hepatomegaly, and hypertriglyceridemia. This led to the clinical diagnosis of congenital generalized lipodystrophy. Importance shouldbe given to the examination of clinical aspects as well as the interdisciplinary follow-up for proper detection of insulin resistance and diabetes, early puberty, cardiomyopathy, among others. In case of Dandy Walker anomaly, it should be checked the evolution to search intracranial hypertension signs. Due to its autosomal recessive nature, it is important to provide genetic counseling to the parents.