title: Dural ectasia and FBN1 mutation screening of 40 patients with Marfan syndrome and related disorders: role of dural ectasia for the diagnosis.
abstract: Marfan syndrome is an autosomal dominant disorder of connective tissue caused by mutations in the gene encoding fibrillin-1 (FBN1), a matrix component of microfibrils. Dural ectasia, i.e. enlargement of the neural canal mainly located in the lower lumbar and sacral region, frequently occurs in Marfan patients. The aim of our study was to investigate the role of dural ectasia in raising the diagnosis of Marfan syndrome and its association with FBN1 mutations. We studied 40 unrelated patients suspected for MFS, who underwent magnetic resonance imaging searching for dural ectasia. In all of them FBN1 gene analysis was also performed. Thirty-seven patients resulted affected by Marfan syndrome according to the '96 Ghent criteria; in 30 of them the diagnosis was confirmed when revaluated by the recently revised criteria (2010). Thirty-six patients resulted positive for dural ectasia. The degree of dural ectasia was grade 1 in 19 patients, grade 2 in 11 patients, and grade 3 in 6 patients. In 7 (24%) patients, the presence of dural ectasia allowed to reach a positive score for systemic feature criterion. Twenty-four patients carried an FBN1 mutation, that were represented by 13 missense (54%), and 11 (46%) mutations generating a premature termination codon (PTC, frameshifts and stop codons). No mutation was detected in the remaining 16 (6 patients with MFS and 10 with related disorders according to revised Ghent criteria). The prevalence of severe (grade 2 and grade 3) involvement of dura mater was higher in patients harbouring premature termination codon (PTC) mutations than those carrying missense-mutations (8/11 vs 2/13, P = 0.0111). Our data emphasizes the importance of dural ectasia screening to reach the diagnosis of Marfan syndrome especially when it is uncertain and indicates an association between PTC mutations and severe dural ectasia in Marfan patients.
authors.affiliation: Department of Medical and Surgical Critical Care, University of Florence, Viale Morgagni 85, 50134 Florence, Italy. monicattanasioit@yahoo.it
authors.forename: Monica
authors.initials: M
authors.lastname: Attanasio
authors.forename: Elisa
authors.initials: E
authors.lastname: Pratelli
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Porciani
authors.forename: Lucia
authors.initials: L
authors.lastname: Evangelisti
authors.forename: Elena
authors.initials: E
authors.lastname: Torricelli
authors.forename: Giannantonio
authors.initials: G
authors.lastname: Pellicanò
authors.forename: Rosanna
authors.initials: R
authors.lastname: Abbate
authors.forename: Gian Franco
authors.initials: GF
authors.lastname: Gensini
authors.forename: Guglielmina
authors.initials: G
authors.lastname: Pepe
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D004108:Dilatation, Pathologic; D005260:Female; D000071838:Fibrillin-1; D000071837:Fibrillins; D005820:Genetic Testing; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008382:Marfan Syndrome / Q000175:diagnosis* / Q000235:genetics; D008840:Microfilament Proteins / Q000235:genetics*; D008875:Middle Aged; D009154:Mutation; D009436:Neural Tube Defects / Q000175:diagnosis*; D013116:Spinal Cord / Q000473:pathology*; D054392:Adipokines
chemical_list: D000071838:Fibrillin-1; D000071837:Fibrillins; D008840:Microfilament Proteins; C000605722:FBN1 protein, human; D054392:Adipokines
keywords: DE; Dural ectasia; Ectopia Lentis syndrome; FBN1 gene; Genotype–phenotype correlation; MFS; Marfan syndrome; PTC; PTC mutation; SEL; TAA; dural ectasia; premature termination codon; thoracic aortic aneurysm