Bardet-Biedl Syndrome

Abstract

SummaryBackground and Objectives Bardet-Biedl Syndrome (BBS) is a rare autosomal recessive ciliopathy with a wide spectrum of clinical features including obesity, retinitis pigmentosa, polydactyly, mental retardation, hypogonadism, and renal abnormalities. The molecular genetic profile of BBS is currently being investigated after the recent identification of 14 BBS genes involved in primary cilia-linked disease. This study aims to characterize the renal and cardiovascular presentations and to analyze possible relationships between genotypes and clinical phenotypes. Design, setting, participants & measurementsThis clinical study was performed in a national cohort of 33 BBS patients, 22 men and 11 women, all aged Ͼ16 years (mean age 26.3 years).Results Renal abnormalities, including impairment of renal function and signs of chronic interstitial nephropathy of dysplastic nature, were documented in 82% of the patients. Cardiovascular evaluations revealed that this group of young patients had significant cardiovascular risk factors. Hypertension was found in Ͼ30% of the patients and hyperlipidemia in Ͼ60%, and almost 50% had other metabolic abnormalities. Overt diabetes was present in only 6%. With regard to genotype-phenotype correlation, patients with a mutation in the BBS6, BBS10, or BBS12 gene (10 of 33 patients) had more severe renal disease. ConclusionsOur study results confirm the frequent occurrence of renal involvement in patients with BBS, underscore the high risk of cardiovascular disease in these patients, and provide new information on a possible genotype-phenotype correlation.

Bardet Biedl syndrome in South Africa: A single founder mutation

“…[8,9] An age-related evolution of the phenotype is well documented in BBS, [1,6] and the younger age distribution of our cohort may have influenced this. Primary enuresis was common into late childhood and adolescence in our cohort, and likely reflects the recognised urinary concentration deficits that occur in BBS.…”

“…[5] Additional reports have expanded both the ocular and systemic phenotype. [6][7][8][9] BBS is typically an autosomal recessive disorder. Although oligogenic inheritance is described, it is a highly heterogeneous condition and to date 21 genes (BBS 1-19, NPHP1 and IFT172) that account for more than 80% of affected individuals have been implicated.…”

“…Primary enuresis was common into late childhood and adolescence in our cohort, and likely reflects the recognised urinary concentration deficits that occur in BBS. [8] Prospective studies have shown cardiovascular abnormalities in up to 52% of BBS patients [9] and an incidence of congenital heart disease in BBS of 7 -19%. [1,7] With the exception of two patients with hypertension, clinically significant cardiovascular abnormalities were not encountered in our cohort.…”

Bardet–Biedl Syndrome: A Rare Cause of Chronic Kidney Disease

“…Prakash [9] reported another 30-yearold patient with BBS who had cysts in the left kidney with normal renal function. ESRD in BBS patients has been reported at age range of 4-57 years [2][3][4][5][15][16][17][18][19]. Management of BBS is supportive and includes training and rehabilitation for blind and mentally retarded patients, hearing aids for deafness, and diet and exercise for obesity.…”

“…Still, it represents a very rare indication for renal transplantation [8,15,16]. Such renal transplant patients are known to be at increased risk for the development of severe obesity, malignancies and cardiovascular complications after transplantation [17].…”