A Significant but Transient Decrease of Factor XIII in an 8-year-old Boy with Subaponeurotic Hematoma

Abstract

An 8-year-old boy who had a subaponeurotic hematoma with a significantly low level of factor XIII (F XIII) was experienced. There was no abnormality in platelet counts and in the solidification function screening test. But the F XIII level decreased to 13% on the 6th day after onset (the lowest level was 6%). The hematoma was gradually improved by the frequent intravenous administration of F XIII concentrate. The activity of F XIII stayed below 70% for the first 4 months, but the patient recovered well without hemorrhage after that, and the F XIII level has been normal. We suspected that a significant decrease of the F XIII level is caused by a massive hematoma and a transient appearance of antibody against the F XIII subunits. In cases of prolonged bleeding with normal platelet counts and a normal test result of solidification function screening, a decrease of F XIII activity should be suspected.