Deep brain stimulation in Bassen-Kornzweig syndrome: Still effective after 22 years.

Introduction: Bassen-Kornzweig syndrome or abetalipoproteinemia is a rare autosomal recessive disorder characterized by a malabsorption of dietary fat and fat-soluble vitamins. This deficiency can lead to a variety of symptoms, including hematological (acanthocytosis, bleeding tendency), neurological (tremor, spinocerebellar ataxia), neuromuscular (myopathy), ophthalmological symptoms (retinitis pigmentosa). The thalamic ventral intermediate nucleus (VIM) is a well-established target for deep brain stimulation (DBS) in the treatment of refractory tremor. Research question: We evaluated the clinical long-term follow-up (22 years) after VIM-DBS for refractory tremor in abetalipoproteinemia. We also evaluated the adjustments of stimulation settings and medication balance after DBS procedure. Material and methods: We report a 53-year-old male who suffers from abetalipoproteinemia since the age of 17. He underwent bilateral VIM-DBS to treat his disabling refractory intentional tremor at the age of 31. He still has a very good response to his tremor with limited stimulation adaptations over 22 years. For more than two decades follow-up, the treatment significantly improved his ADL functions and therefore also the QoL. Discussion and conclusion: The VIM target for DBS in the treatment of refractory tremor has been extensively reported in the literature. Thalamic VIM-DBS is a safe and effective treatment for a severe, refractory tremor as a neurological symptom caused by abetalipoproteinemia. It also highlights the importance of a multidisciplinary follow-up, to adjust and optimize the stimulation/medication balance after VIM-DBS surgery.

Inborn Errors of Metabolism with Ataxia: Current and Future Treatment Options.

A number of hereditary ataxias are caused by inborn errors of metabolism (IEM), most of which are highly heterogeneous in their clinical presentation. Prompt diagnosis is important because disease-specific therapies may be available. In this review, we offer a comprehensive overview of metabolic ataxias summarized by disease, highlighting novel clinical trials and emerging therapies with a particular emphasis on first-in-human gene therapies. We present disease-specific treatments if they exist and review the current evidence for symptomatic treatments of these highly heterogeneous diseases (where cerebellar ataxia is part of their phenotype) that aim to improve the disease burden and enhance quality of life. In general, a multimodal and holistic approach to the treatment of cerebellar ataxia, irrespective of etiology, is necessary to offer the best medical care. Physical therapy and speech and occupational therapy are obligatory. Genetic counseling is essential for making informed decisions about family planning.

Consideraciones clínicas de la abetalipoproteinemia: revisión de la literatura / Clinical considerations of abetalipoproteinemia: literature review

La abetalipoproteinemia es una enfermedad rara que se suele presentarse en la primera década de la vida; sus principales manifestaciones son esteatorrea, alteración en el desarrollo y niveles plasmáticos lipídicos onsiderablemente disminuidos. Sin embargo, este cuadro suele ser confuso, puesto que existe un grupo de desórdenes genéticos que conllevan a mala absorción lipídica, que requieren un exhaustivo diagnóstico diferencial desde el punto de vista clínico, bioquímico y molecular. Este artículo expone una revisión actualizada sobre la abetalipoproteinemia, enfocándose en su fisiopatología, manifestaciones sistémicas, diagnóstico y abordaje en general, para facilitar su comprensión integral. La estrategia de búsqueda y los métodos de selección de estudios se realizó con base en elementos de la declaración prisma y guías Cochrane, utilizando términos de búsqueda tales como "abetalipoproteinemia" ,"bioquímica" y sinónimos, los cuales fueron combinados con los operadores "and" y "or", en las bases de datos PubMed, Science Direct, Clinical Key y Ebsco. No existe mucha literatura específica sobre esta condición, lo cual explica que sea una entidad subvalorada y poco conocida. Es fundamental realizar más investigaciones en torno al tema, pues en caso de no establecerse un diagnóstico y manejo adecuado, las complicaciones serán muchas y severas..Au

Abetalipoproteinemia is a rare disease that occurs predominantly in the first decade of life, having as main manifestations, steatorrhea, alteration in development and considerably decreased lipid plasma levels. However, this clinical presentation is often confusing, since there is a group of genetic disorders that lead to poor lipid absorption, requiring the need to make a comprehensive differential diagnosis from a clinical, biochemical and molecular point of view. This article will provide an updated review on Abetalipoproteinemia, focusing on its pathophysiology, systemic manifestations, diagnosis and general approach, allowing easy access to an integral knowledge. The search strategy and study selection methods were based on elements of the prisma statement and Cochrane guidelines, using search terms such as "Abetalipoproteinemia" and "Biochemistry", in addition to synonyms, which were combined with "and" and "or" operators, in the PubMed, Science Direct, Clinical Key and Ebsco databases. It is necessary to highlight that there is not much specific literature on this condition, which would support the fact that it is an undervalued and little-known entity, it is essential to carry out more research on the subject, taking into account that if a diagnosis is not established proper management, the complications are many and severe..Au

Normal serum ApoB48 and red cells vitamin E concentrations after supplementation in a novel compound heterozygous case of abetalipoproteinemia.

BACKGROUND AND AIMS: Abetalipoproteinemia (ABL) is a rare recessive monogenic disease due to MTTP (microsomal triglyceride transfer protein) mutations leading to the absence of plasma apoB-containing lipoproteins. Here we characterize a new ABL case with usual clinical phenotype, hypocholesterolemia, hypotriglyceridemia but normal serum apolipoprotein B48 (apoB48) and red blood cell vitamin E concentrations. METHODS: Histology and MTP activity measurements were performed on intestinal biopsies. Mutations in MTTP were identified by Sanger sequencing, quantitative digital droplet and long-range PCR. Functional consequences of the variants were studied in vitro using a minigene splicing assay, measurement of MTP activity and apoB48 secretion. RESULTS: Intestinal steatosis and the absence of measurable lipid transfer activity in intestinal protein extract supported the diagnosis of ABL. A novel MTTP c.1868G>T variant inherited from the patient's father was identified. This variant gives rise to three mRNA transcripts: one normally spliced, found at a low frequency in intestinal biopsy, carrying the p.(Arg623Leu) missense variant, producing in vitro 65% of normal MTP activity and apoB48 secretion, and two abnormally spliced transcripts resulting in a non-functional MTP protein. Digital droplet PCR and long-range sequencing revealed a previously described c.1067+1217_1141del allele inherited from the mother, removing exon 10. Thus, the patient is compound heterozygous for two dysfunctional MTTP alleles. The p.(Arg623Leu) variant may maintain residual secretion of apoB48. CONCLUSIONS: Complex cases of primary dyslipidemia require the use of a cascade of different methodologies to establish the diagnosis in patients with non-classical biological phenotypes and provide better knowledge on the regulation of lipid metabolism.

Causes Of Chronic Non-Infectious Diarrhoea In Infants Less Than 6 Months Of Age: Rarely Recognized Entities.

BACKGROUND: Non-infectious causes of chronic diarrhoea are important and easily missed. The study was done with the objectives to identify different causes of chronic non-infectious diarrhoea in infants less than 6 months of age. METHODS: All patients less than 6 months of age presenting for the first time to a Paediatric Gastroenterology tertiary care centre with a history of chronic diarrhoea and negative stool cultures were enrolled over a period of 8 months. Demographical profile and various factors under observation were recorded in this observational study. Collected data was analysed using SPSS version 20. Chi square test was applied as a test of significance for any qualitative variable, p value (p<0.05) was taken as significant. RESULTS: Among 72 enrolled patients, female to male ratio was1.05:1. Age at onset of symptoms was between 15 days to 6 months. Aetiology found was Cow's milk protein allergy (CMPA) in 58 (80.6%), Primary intestinal lymphangiectasia (PIL) 6 (8.3%), Cystic fibrosis (CF) 3 (4.2%), Immunodeficiency (SCID) 2 (2.8%), 1 (1.4%) for each Abetalipoproteinemia (ABL), Glucose galactose malabsorption (GGM) and Congenital chloride diarrhoea (CCD). CONCLUSIONS: Among noninfectious causes of chronic diarrhoea in early infancy, cow's milk protein allergy is most common followed by Primary intestinal lymphangiectasia and Cystic fibrosis.

Update on the molecular biology of dyslipidemias.

Dyslipidemia is a commonly encountered clinical condition and is an important determinant of cardiovascular disease. Although secondary factors play a role in clinical expression, dyslipidemias have a strong genetic component. Familial hypercholesterolemia is usually due to loss-of-function mutations in LDLR, the gene coding for low density lipoprotein receptor and genes encoding for proteins that interact with the receptor: APOB, PCSK9 and LDLRAP1. Monogenic hypertriglyceridemia is the result of mutations in genes that regulate the metabolism of triglyceride rich lipoproteins (eg LPL, APOC2, APOA5, LMF1, GPIHBP1). Conversely familial hypobetalipoproteinemia is caused by inactivation of the PCSK9 gene which increases the number of LDL receptors and decreases plasma cholesterol. Mutations in the genes APOB, and ANGPTL3 and ANGPTL4 (that encode angiopoietin-like proteins which inhibit lipoprotein lipase activity) can further cause low levels of apoB containing lipoproteins. Abetalipoproteinemia and chylomicron retention disease are due to mutations in the microsomal transfer protein and Sar1b-GTPase genes, which affect the secretion of apoB containing lipoproteins. Dysbetalipoproteinemia stems from dysfunctional apoE and is characterized by the accumulation of remnants of chylomicrons and very low density lipoproteins. ApoE deficiency can cause a similar phenotype or rarely mutations in apoE can be associated with lipoprotein glomerulopathy. Low HDL can result from mutations in a number of genes regulating HDL production or catabolism; apoAI, lecithin: cholesterol acyltransferase and the ATP-binding cassette transporter ABCA1. Patients with cholesteryl ester transfer protein deficiency have markedly increased HDL cholesterol. Both common and rare genetic variants contribute to susceptibility to dyslipidemias. In contrast to rare familial syndromes, in most patients, dyslipidemias have a complex genetic etiology consisting of multiple genetic variants as established by genome wide association studies. Secondary factors, obesity, metabolic syndrome, diabetes, renal disease, estrogen and antipsychotics can increase the likelihood of clinical presentation of an individual with predisposed genetic susceptibility to hyperlipoproteinemia. The genetic profiles studied are far from complete and there is room for further characterization of genes influencing lipid levels. Genetic assessment can help identify patients at risk for developing dyslipidemias and for treatment decisions based on 'risk allele' profiles. This review will present the current information on the genetics and pathophysiology of disorders that cause dyslipidemias.

Hipobetalipoproteinemia primária: relato de caso / Primary Hypobetalipoproteinemia: a case report

Descrevemos o caso de uma paciente de 19 anos diagnosticada com hipobetalipoproteinemia primária. A paciente apresentava sintomas compatíveis com a doença como diarreia desde o primeiro mês de vida, défice de crescimento e retinopatia. A biópsia duodenal evidenciou presença de vacúolos lipídicos intraepiteliais, os quais foram altamente sugestivos para o diagnóstico. Os exames complementares evidenciaram disfunção hepática, baixos níveis séricos de triglicerídeos, e de colesterol total e frações. Após a dosagem de apolipoproteína B abaixo dos valores da normalidade, aliada a clínica e exames complementares, o diagnóstico foi realizado. A relativa escassez de dados na literatura em nosso meio, atrelada à raridade da doença, ilustra a relevância deste relato de caso, somado à importância do diagnóstico precoce

The case of a 19-year-old female patient who was diagnosed with Primary Hypobetalipoproteinemia (HBL) is described.The patient presented symptoms that were consistent with the disease, such as diarrhea from the very first month of life, growth failure and retinopathy. The duodenal biopsy showed the presence of intraepithelial lipid vacuoles that were highly suggestive of the diagnosis. Further tests showed liver dysfunction, low serum levels of triglycerides and total cholesterol and fractions. After the dosage of Apolipoprotein B below normal values, and clinical exam along with laboratory tests, the diagnosis was made. The lack of data in the literature and the rarity of the disease illustrate the importance of this case report,and of an early diagnosis.

A Male Infant with Abetalipoproteinemia: A Case Report from Iran.

Abetalipoproteinemia (ABL) is a very rare autosomal recessive disorder caused by mutations in the microsomal triglyceride transfer protein gene (MTTP). ABL is characterized by lack of lipids and apolipoprotein B (apoB) in plasma, fat malabsorption and various clinical manifestations. We describe a 12-month-old infant boy, born from consanguineous parents and presented with diarrhea, steatorrhea, growth retardation, hypothyroidism, intraventricular brain cyst and kidney stones. The patient was diagnosed to have ABL and treated with dietary modification and oral fat-soluble vitamin replacement and followed until he reached 5 years of age.

O relato de caso como situação gnosiológica: reflexões sobre a prática diagnóstica em patologia a partir de um caso de abetalipoproteinemia / The case report as a gnosiological situation: reflections on diagnostic pathology, based on a case of abetalipoproteinemia

Neste ensaio, aproveita-se um caso raro de abetalipoproteinemia, diagnosticado a partir dos achados anatomopatológicos de biópsia jejunal, para refletir sobre a prática diagnóstica em patologia. Mais do que narrar o caso e comentar seu conteúdo, como usualmente se faz nos relatos de caso, o caso, como objeto de estudo, pode ser empregado como matéria para reflexão sobre a prática. O caso é objeto mediatizador da reflexão que se faz sobre a prática, possibilitando um desvelamento da realidade, na qual se insere o exercício da medicina.

This article draws on a rare case of abetalipoproteinemia, diagnosed from the pathological findings of a jejunal biopsy, as the point of departure for reflecting on practice in diagnostic pathology. Rather than present a case and comment on its content, as usually happens in case reports, the case, as object of study, can be used as material for reflection on practice. The case is the mediating object of reflection on the practice, allowing an unveiling of reality in which medical practice is a part.