title: Significance of red cell distribution width in the differential diagnosis between neurally mediated syncope and arrhythmic syncope in children.
abstract: OBJECTIVE
  The aim of the present study was to explore the predictive value of red cell distribution width as a means to differentiate between neurally mediated syncope and arrhythmic syncope in children.
  
  
  METHODS
  Patients were divided into a neurally mediated syncope group (n=72) and an arrhythmic syncope group (n=21) on the basis of clinical history, results of the head-up tilt test, electrocardiography, and 24-hour ambulatory electrocardiography. As controls, we recruited 55 healthy children. Red cell distribution width was determined for children in all groups. A receiver operating characteristic curve was drawn to study the predictive effect of red cell distribution width to differentiate between neurally mediated syncope and arrhythmic syncope.
  
  
  RESULTS
  Red cell distribution width was significantly higher in children with neurally mediated syncope than in children with arrhythmic syncope and the control group. A receiver operating characteristic curve on the predictive value of red cell distribution width in differentiating neurally mediated syncope from arrhythmic syncope showed that the area under the curve was 0.841 (95% confidence interval: 0.737-0.945, p<0.05). A red cell distribution width value of 12.8% as the cut-off value yielded a sensitivity of 80.6% and a specificity of 76.2% in discriminating between patients with neurally mediated syncope and arrhythmic syncope.
  
  
  CONCLUSIONS
  Red cell distribution width value of ⩾12.8% might be a useful adjunct for primary-care physicians to differentiate neurally mediated syncope from arrhythmic syncope in children.
authors.affiliation: Department of Pediatrics,Peking University First Hospital,Beijing,China.
authors.forename: Qingyou
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Pediatrics,Peking University First Hospital,Beijing,China.
authors.forename: Yaqi
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Pediatrics,Peking University First Hospital,Beijing,China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Liao
authors.affiliation: Department of Pediatrics,Peking University First Hospital,Beijing,China.
authors.forename: Junbao
authors.initials: J
authors.lastname: Du
mesh_terms: D001145:Arrhythmias, Cardiac / Q000150:complications* / Q000175:diagnosis; D000068476:Beijing; D016022:Case-Control Studies; D002648:Child; D003937:Diagnosis, Differential; D015716:Electrocardiography, Ambulatory; D004909:Erythrocyte Indices; D005260:Female; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D012372:ROC Curve; D019462:Syncope, Vasovagal / Q000097:blood* / Q000175:diagnosis*; D018667:Tilt-Table Test
keywords: Red cell distribution width; arrhythmic syncope; children; syncope