Progress in pathogenesis, diagnosis, and treatment of Alstrom syndrome / 国际儿科学杂志

Alstrom syndrome(ALMS)is a rare autosomal recessive disorder involving multiple systems.The main clinical manifestations include nystagmus, hearing loss, obesity, insulin resistance, type 2 diabetes, dilated cardiomyopathy, etc.Primary cilia are key organelles.ALMS is classified as a ciliopathy, mainly related to the mutation of ALMS1 gene which affects cilia function, but the specific mechanism remains unclear.At present, the diagnosis of ALMS mainly relies on clinical manifestations and gene sequencing.There are no specific and effective treatment methods except for symptomatic treatment, but early diagnosis and intervention can delay disease progression and improve patients′ quality of life.This article reviews recent advances in the pathogenesis, diagnosis, and treatment of ALMS.

Progress in pathogenesis, diagnosis, and treatment of Alstrom syndrome / 国际儿科学杂志

Alstrom syndrome (ALMS) is a rare autosomal recessive disorder involving multiple systems.The main clinical manifestations include nystagmus,hearing loss,obesity,insulin resistance,type 2 diabetes,dilated cardiomyopathy,etc.Primary cilia are key organelles.ALMS is classified as a ciliopathy,mainly related to the mutation of ALMS1 gene which affects cilia function,but the specific mechanism remains unclear.At present,the diagnosis of ALMS mainly relies on clinical manifestations and gene sequencing.There are no specific and effective treatment methods except for symptomatic treatment,but early diagnosis and intervention can delay disease progression and improve patients' quality of life.This article reviews recent advances in the pathogenesis,diagnosis,and treatment of ALMS.

Morphological and functional findings in Alström syndrome: a study of two families / Achados morfológicos e funcionais na síndrome de Alström: um estudo de duas famílias

ABSTRACT Alström syndrome is a rare disorder characterized by mutations to the ALMS1 gene and clinical findings of childhood obesity, diabetes mellitus, dilated cardiomyopathy, sensorineural hearing loss, and progressive cone-rod dystrophy, which may result in blindness. Ocular manifestations occur in the first decade of life with nystagmus, blepharospasm, and photophobia leading to progressive and severe reductions in visual acuity. This study describes the retinal structure and functional aspects of four patients (8 eyes) from two different families as determined by optical coherence tomography (OCT), fundus autofluorescence, and full-field electroretinography. There was a correlation between morphological and functional findings, evidenced by typical funduscopic changes of retinal dystrophy in spectral domain-OCT and electrophysiological analyses. Foveal characteristics include a single layer of undifferentiated photoreceptors with retinal disorganization mainly from external segments, in agreement with previous reports in the literature. Fundus autofluorescence showed areas of hyperautofluorescence interspersed by hypoautofluorescence dots suggesting, respectively, involvement and atrophy of retinal pigmented epithelial cells in the macular zone. Electroretinographic analyses showed early dysfunction of the cones followed by rapid rod deterioration.

RESUMO A síndrome de Alström é uma doença rara caracterizada por mutações no gene AMLS 1 e achados clínicos de obesidade infantil, diabetes mellitus, cardiomiopatia dilatada, surdez neurossensorial e distrofia de cones e bastonetes progressiva, que podem resultar em cegueira. Manifestações oftalmológicas ocorrem na primeira década de vida com nistagmo, blefaroespasmo e fotofobia, levando a reduções progressivas e graves na acuidade visual. Este estudo descreve a estrutura da retina e os aspectos funcionais de quatro pacientes (oito olhos) de duas famílias dis tintas, conforme determinado por tomografia de coerência óptica, autoflourescência de fundo de olho e eletrorretinograma de campo total. Houve correlação entre os achados morfológicos e funcionais evidenciados por alterações fundoscópicas típicas da distrofia retiniana no domínio espectral-OCT e análises eletrofisiológicas. As características foveais incluem uma única camada de fotorreceptores indiferenciados com desorganização retiniana principalmente nos segmentos externos, de acordo com relatos prévios da literatura. A autofluorescência de fundo mostrou áreas de hiperautofluorescência, sugerindo, respectivamente, envolvimento e atrofia das células do epitélio pigmentar da retina na região macular. Análises eletrorretinográficas mostram disfunção precoce de cones, seguida de rápida deteriorização da haste.

Alstrom syndrome in children:a case report and literature review / 临床儿科杂志

Objective To analyze the clinical feature, diagnosis and treatment of Alstrom syndrome. Method The clinical data of a case of Alstrom syndrome and the result of her ALMS1 sequencing by the two generation sequencing were retrospectively reviewed. Results The 12 year and 10 month old female suffered from dilated cardiomyopathy, obesity, optic nerve diseases, sensorineural hearing loss, high blood glucose and irregular menstruation since one month of birth. Laboratory examination showed she had high testosterone level, hyperglycemia, hyperlipidemia and fatty liver. High-throughput sequencing confirmed there was ALMS1 gene mutation which includes hybrid frameshift mutations of c.5418delC and p.Y1807Tfs*23, and heterozygous nonsense mutation of c.10549C>T and p.Q3517*, and c.5418delC was a new variation reported for the first time. Conclusion Alstrom syndrome is an autosomal recessive genetic disease, which is characterized by multiple organ dysfunction and metabolic syndrome, and can be diagnosed by gene detection.

Identification of Two Cases of Ciliopathy-Associated Diabetes and Their Mutation Analysis Using Whole Exome Sequencing

BACKGROUND: Alstrom syndrome and Bardet-Biedl syndrome are autosomal recessively inherited ciliopathies with common characteristics of obesity, diabetes, and blindness. Alstrom syndrome is caused by a mutation in the ALMS1 gene, and Bardet-Biedl syndrome is caused by mutations in BBS1-16 genes. Herein we report genetically confirmed cases of Alstrom syndrome and Bardet-Biedl syndrome in Korea using whole exome sequencing. METHODS: Exome capture was done using SureSelect Human All Exon Kit V4+UTRs (Agilent Technologies). HiSeq2000 system (Illumina) was used for massive parallel sequencing. Sanger sequencing was used for genotype confirmation and familial cosegregation analysis. RESULTS: A 21-year old Korean woman was clinically diagnosed with Alstrom syndrome. She had diabetes, blindness, obesity, severe insulin resistance, and hearing loss. Whole exome sequencing revealed a nonsense mutation in exon 10 of ALMS1 (c.8776C>T, p.R2926X) and a seven base-pair deletion resulting in frameshift mutation in exon 8 (c.6410_6416del, p.2137_2139del). A 24-year-old Korean man had Bardet-Biedl syndrome with diabetes, blindness, obesity, and a history of polydactyly. Whole exome sequencing revealed a nonsynonymous mutation in exon 11 of the BBS1 gene (c.1061A>G, p.E354G) and mutation at the normal splicing recognition site of exon 7 of the BBS1 gene (c.519-1G>T). CONCLUSION: We found novel compound heterozygous mutations of Alstrom syndrome and Bardet-Biedl syndrome using whole exome sequencing. The whole exome sequencing successfully identified novel genetic variants of ciliopathy-associated diabetes.

A Case of Alstrom Syndrome / 대한내분비학회지

The Alstrom syndrome is inherited autosomal recessive disorder, characterized by obesity, diabetes mellitus, pigmentary retinal degeneration, normal intelligence, sensorineural hearing loss, baldness, acanthosis nigricans, male hypogonadism, hyperuricemia and hypertriglyceridemia. There is no reported case of Alstrom syndrome in Korea yet. We experienced a 29-year-old female patient with clinical characteristics similar to Alstrom syndrome who was admitted due to poorly controlled diabetes mellitus and diabetic retinopathy with hemorrhage. We report this case with the review of literatures.