title: False findings of low protein C activity in two children with Budd-Chiari syndrome and factor V Leiden mutation.
abstract: Two pediatric patients with Budd-Chiari syndrome are reported, who were heterozygous for factor V Leiden mutation. The first patient was falsely diagnosed with type II protein C deficiency, and the second was initially found to have decreased protein C activity based on a protein C clotting assay. Retesting by protein C chromogenic assay indicated that protein C activity was normal in both children. In patients with Budd-Chiari syndrome, low levels of protein C antigen and activity should be interpreted with caution, and within the context of factor V Leiden mutation status, parents' results, severity of liver dysfunction, and the type of protein C assay performed in order to avoid misdiagnosing protein C deficiency.
authors.affiliation: Department of Pediatrics, Başkent University, Faculty of Medicine, Ankara, Turkey. fozcay@superonline.com
authors.forename: Figen
authors.initials: F
authors.lastname: Ozçay
authors.forename: Namik
authors.initials: N
authors.lastname: Ozbek
mesh_terms: D006502:Budd-Chiari Syndrome / Q000097:blood* / Q000150:complications / Q000235:genetics; D002648:Child; D002863:Chromogenic Compounds; D005165:Factor V / Q000235:genetics*; D005189:False Positive Reactions; D005192:Family Health; D006579:Heterozygote; D006801:Humans; D017093:Liver Failure / Q000209:etiology; D008297:Male; D011486:Protein C / Q000032:analysis*; D020151:Protein C Deficiency / Q000175:diagnosis*
chemical_list: D002863:Chromogenic Compounds; D011486:Protein C; C095381:factor V Leiden; D005165:Factor V