title: The prevalence of bleeding disorders among healthy pediatric patients with abnormal preprocedural coagulation studies.
abstract: BACKGROUND
  We evaluated the prevalence of hemostatic disorders among pediatric patients with abnormal screening coagulation tests.
  
  
  METHODS
  We analyzed 48 consecutive referrals for abnormal prothrombin times, partial thromboplastin times, or closure times obtained as preprocedural screens. Patients were evaluated by uniform diagnostic testing.
  
  
  RESULTS
  Seventeen patients (35%) had an isolated nonspecific inhibitor (NSI). Six patients (12.5%) presented with mildly low factor activity with a concomitant NSI. These deficiencies were of unclear clinical significance. One patient (2%) had a lupus anticoagulant. Only 9 patients (19%) had a possible or true mild bleeding disorder: 5 patients (10%) had isolated low von Willebrand factor levels, 2 patients (4%) had possible type I von Willebrand disease, and 2 (4%) had platelet aggregation disorders. In all patients, personal and family bleeding history had a positive predictive value of 45% for hemostatic disorders.
  
  
  CONCLUSIONS
  The most common diagnosis among the patients referred to us for abnormal preoperative coagulation tests was a NSI, which is not associated with an increased risk of operative bleeding complications. Less than 20% had a possible or true mild bleeding disorder. Although certain bleeding disorders can be occult in children and are associated with perioperative bleeding risks, our study demonstrates the inherent limitations in making a laboratory diagnosis of a bleeding disorder in pediatric patients preoperatively. Our findings contribute to existing doubt about the usefulness of prothrombin times, partial thromboplastin times, and closure times to identify occult bleeding disorders in this population.
authors: Division of Hematology/Oncology, University of Pittsburgh School of Medicine and Children's Hospital of Pittsburgh, Pittsburgh, PA 15213-2583, USA. shawph@chp.edu
authors: Peter H
authors: PH
authors: Shaw
authors: Stacy
authors: S
authors: Reynolds
authors: Sriya
authors: S
authors: Gunawardena
authors: Lakshamanan
authors: L
authors: Krishnamurti
authors: Arthur Kim
authors: AK
authors: Ritchey
mesh_terms: D000293:Adolescent; D000328:Adult; D001778:Blood Coagulation Disorders / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D010036:Otolaryngology; D010314:Partial Thromboplastin Time; D015995:Prevalence; D011517:Prothrombin Time; D012017:Referral and Consultation; D014842:von Willebrand Diseases / Q000175:diagnosis