title: A clinical and cardiovascular survey of Ehlers-Danlos syndrome patients with complete deficiency of tenascin-X.
abstract: BACKGROUND
  We recently described a new autosomal recessive type of Ehlers-Danlos syndrome (EDS) based on a deficiency of the extracellular matrix protein tenascin-X (TNX). TNX-deficient patients have hypermobile joints, hyperextensible skin and show easy bruising. Because of the reported cardiovascular abnormalities in other EDS types and the excessive haematoma formation after mild trauma in TNX-deficient individuals, we investigated whether cardiovascular or coagulation abnormalities occur in these patients.
  
  
  METHODS
  We examined seven TNX-deficient patients. One of them had a mitral valve prolapse and died postoperatively after valve replacement, before the study was completed.
  
  
  RESULTS
  Bleeding time and coagulation factors (INR, APTT, PT and fibrinogen) were all within the normal range. Ultrasonographic examination of the carotid and femoral arteries showed normal vessel wall compliance and distensibility. Echocardiography showed a slight billowing of the mitral valve in two patients from one family. All patients had normal diameters of aortic root and ascending aorta.
  
  
  CONCLUSIONS
  Although the patient group is small, there are no indications of generalised cardiovascular abnormalities in this type of EDS. We would recommend echocardiography for all these patients at the first evaluation and when a cardiac murmur appears.
authors.affiliation: University Medical Centre St Radboud, Nijmegen, The Netherlands.
authors.forename: A C T M
authors.initials: AC
authors.lastname: Peeters
authors.forename: M
authors.initials: M
authors.lastname: Kucharekova
authors.forename: J
authors.initials: J
authors.lastname: Timmermans
authors.forename: F W P J
authors.initials: FW
authors.lastname: van den Berkmortel
authors.forename: G H J
authors.initials: GH
authors.lastname: Boers
authors.forename: I R O
authors.initials: IR
authors.lastname: Nováková
authors.forename: D
authors.initials: D
authors.lastname: Egging
authors.forename: M
authors.initials: M
authors.lastname: den Heijer
authors.forename: J
authors.initials: J
authors.lastname: Schalkwijk
mesh_terms: D004452:Echocardiography; D004535:Ehlers-Danlos Syndrome / Q000150:complications / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008945:Mitral Valve Prolapse / Q000150:complications / Q000000981:diagnostic imaging; D019063:Tenascin / Q000172:deficiency*
chemical_list: D019063:Tenascin; C081865:tenascin X