Asymptomatic factor VII deficiency: gene analysis and structure-function relationships.
Factor VII Padua is a variant form of factor VII deficiency characterized by a prolongation of the prothrombin time (PT), when the assay is performed using rabbit brain thromboplastin. The PT is normal when performed using either human or ox brain thromboplastin reagents, or a recombinant human tissue factor-based thromboplastin. We report a case of an African-American woman with asymptomatic factor VII deficiency, who had a prolonged PT and factor VII activity levels of 5-8% using rabbit brain thromboplastin, but a normal PT and factor VII activity levels when measured using recombinant human brain thromboplastin or tissue factor. The amino acid substitution (R304Q), which gives rise to factor VII Padua, was found in our patient, making this only the fourth African-American case described to date with this mutation. Our report emphasizes the importance of identifying this benign form of factor VII deficiency in order to avoid unnecessary exposure of patients to treatment with either plasma-derived products or recombinant activated factor VII.
Kirkel
Dean
D
Department of Medicine, Division of Hematology-Oncology, The George Washington University School of Medicine and Health Sciences and the Children's National Medical Center, Washington, District of Columbia 20037, USA.
Lin
Ta-Wei
TW
Fu
Sidney W
SW
Dlott
Jeffrey S
JS
Sahud
Mervyn A
MA
McCaffrey
Timothy
T
Rickles
Frederick R
FR
D000818:Animals; D004252:DNA Mutational Analysis; D017558:Elective Surgical Procedures; D005167:Factor VII / Q000737:chemistry / Q000235:genetics*; D005168:Factor VII Deficiency / Q000235:genetics*; D005169:Factor VIII / Q000032:analysis; D005260:Female; D015390:Gastric Bypass; D006801:Humans; D033162:Incidental Findings; D008875:Middle Aged; D010314:Partial Thromboplastin Time; D011300:Preoperative Care; D011517:Prothrombin Time; D011817:Rabbits; D013329:Structure-Activity Relationship
C080432:Factor VII Padua; D005167:Factor VII; D005169:Factor VIII