title: Enlarged Dural Sac in Idiopathic Bronchiectasis Implicates Heritable Connective Tissue Gene Variants.
abstract: Patients with idiopathic bronchiectasis are predominantly female and have an asthenic body morphotype and frequent nontuberculous mycobacterial respiratory infections. They also demonstrate phenotypic features (scoliosis, pectus deformity, mitral valve prolapse) that are commonly seen in individuals with heritable connective tissue disorders.
  
  
  
  To determine whether lumbar dural sac size is increased in patients with idiopathic bronchiectasis as compared with control subjects, and to assess whether dural sac size is correlated with phenotypic characteristics seen in individuals with heritable connective tissue disorders.
  
  
  
  Two readers blinded to diagnosis measured anterior-posterior and transverse dural sac diameter using L1-L5 magnetic resonance images of 71 patients with idiopathic bronchiectasis, 72 control subjects without lung disease, 29 patients with cystic fibrosis, and 24 patients with Marfan syndrome. We compared groups by pairwise analysis of means, using Tukey's method to adjust for multiple comparisons. Dural sac diameter association with phenotypic and clinical features was also tested.
  
  
  
  The L1-L5 (average) anterior-posterior dural sac diameter of the idiopathic bronchiectasis group was larger than those of the control group (P < 0.001) and the cystic fibrosis group (P = 0.002). There was a strong correlation between increased dural sac size and the presence of pulmonary nontuberculous mycobacterial infection (P = 0.007) and long fingers (P = 0.003). A trend toward larger dural sac diameter was seen in those with scoliosis (P = 0.130) and those with a family history of idiopathic bronchiectasis (P = 0.149).
  
  
  
  Individuals with idiopathic bronchiectasis have an enlarged dural sac diameter, which is associated with pulmonary nontuberculous mycobacterial infection, long fingers, and family history of idiopathic bronchiectasis. These findings support our hypothesis that "idiopathic" bronchiectasis development reflects complex genetic variation in heritable connective tissue and associated transforming growth factor-β-related pathway genes.
authors.affiliation: 1 Department of Medicine and.
authors.forename: M Leigh Anne
authors.identifier: 0000-0001-6979-2681
authors.initials: ML
authors.lastname: Daniels
authors.affiliation: 2 Department of Radiology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
authors.forename: Katherine R
authors.initials: KR
authors.lastname: Birchard
authors.affiliation: 3 Department of Medicine, Duke University School of Medicine, Durham, North Carolina; and.
authors.forename: Jared R
authors.initials: JR
authors.lastname: Lowe
authors.affiliation: 4 Eastern Virginia Medical School, Norfolk, Virginia.
authors.forename: Michael V
authors.initials: MV
authors.lastname: Patrone
authors.affiliation: 1 Department of Medicine and.
authors.forename: Peadar G
authors.identifier: 0000-0003-4059-5419
authors.initials: PG
authors.lastname: Noone
authors.affiliation: 1 Department of Medicine and.
authors.forename: Michael R
authors.identifier: 0000-0002-4672-5969
authors.initials: MR
authors.lastname: Knowles
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001987:Bronchiectasis / Q000235:genetics* / Q000473:pathology*; D003550:Cystic Fibrosis / Q000000981:diagnostic imaging / Q000473:pathology; D004388:Dura Mater / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D014644:Genetic Variation; D006801:Humans; D016014:Linear Models; D008161:Lumbosacral Region; D008279:Magnetic Resonance Imaging; D008297:Male; D008382:Marfan Syndrome / Q000000981:diagnostic imaging / Q000473:pathology; D008875:Middle Aged; D009165:Mycobacterium Infections, Nontuberculous / Q000175:diagnosis*; D009170:Nontuberculous Mycobacteria / Q000302:isolation & purification; D013147:Spirometry; D055815:Young Adult
keywords: bronchiectasis; dural sac diameter; heritable connective tissue disorders; nontuberculous mycobacteria