Abstract
A 9 years 2 months old male without consanguinity, was Shown to have congenital factor XIII deficiency whose initial bleeding episodes whre umblical bleeding and cephalohematoma in his newborn period. Thereafter, repeated abnormal bleedings were observed at every traumatic accident and stopped with fresh blood transfusions. At the first visit to our clinic, physical examination revealed tumor of right upper arm due to fresh intramuscular bleeding and ugly scar formation at the forehead and the right femoral area whcih were produced after the surgical manipulation given for hemostatic control at the past bleeding episodes.
Hematologic and coagulation studies revealed no anemia and normal liver function. All of bleeding time, platelet count, PT, PTT and tournique test fell within the normal range. However, remarkable reduction of ma and mε of his thromboelastogram and the increased solubility of patient's clot in 5M urea (75 min.) and 1% monochloracetic acid (within 15 min.) were found. The assay of factor XIII of the patient's plasma was below 1% of normal level by the neutralization test using antiserum of factor XIII and assay of subunits a and b in his plasma were 0% and 45%, respectively Both factor XIII levels of his parents were 50% of normal.
Excellent hemostatic control was obtained by infusion of factor XIII concentrate (500 units) and its half life was three days. The thromboelastogram was also kept within normal range over two weeks after infusion of the concentrates.
Subunit b/a ratio was ∞ in homozygous patient, 1.49 in heterozygous (carriers) and 1.07±0.13 (m±SD, n=9) in control. Analysis of subunit ratio may provide useful method to detect the carriers.
