Acquired Factor XIII Deficiency in the Inpatient Setting: Clinical Suspicion, Impact and Treatment: Retrospective Case Series

Introduction: Activated factor XIII (FXIII) stabilizes fibrin clots at the end of the coagulation cascade by bridging fibrin molecules. Disproportionate surgery related bleeding has been reported in association with FXIII deficiency, in patients with normal coagulopathies screening tests, and without a history of previous bleedings. Methods: Retrospective case series. We performed immunological factor XIIIA (FXIIIA) studies in the inpatient setting of the Hospital Italiano de Buenos Aires, between January 2014 and March 2016. FXIIIA below 50% were considered deficient. Patients with suspicion of congenital Factor XIII deficiency or 2 years old or less were excluded. Descriptive statistics were used. Populations were compared with chi-square, Fisher and T test, or Mann Whitney tests with Stata13 software. Results: FXIII was studied in 52 patients; 37 of these (26 females and 11 males) met inclusion and exclusion criteria. Median age was 43 years (range 9-81). Twenty two patients were studied because of disproportionate surgery related bleeding, 11 because of spontaneous bleeding; and 4 not specified. All patients presented normal coagulopathies screening tests, normal Von Willebrand factor and ristocetine cofactor activity and normal platelet function tests. Eleven patients (30%) had FXIIIA less than 50%. Statistically significant differences between groups were found for median drop in hematocrit points [3.5 (IQR 3-10) vs 1.5 (IQR 0-2, p=0.02)] and median number of red cell units transfused [4 (IQR 0-6) vs 0 (0-2), p=0.01]. Differences in rates of minor and major bleedings were not statistically significant. Only one patient of eleven presented FXIII deficiency associated spontaneous bleeding vs 8 out of 20 patients in the postsurgical setting. FXIII concentrate was used in two patients to treat persistent bleeding, resolving in less than 24 hours. Three patients died, none because of bleeding. Five of the 11 patients with FXIII deficiency returned to normal values when FXIII assay was repeated away from acute setting. Discussion: FXIII acquired deficiency is associated with disproportionate bleeding in postsurgical setting in patients without apparent coagulation defects. FXIII deficiency could be underdiagnosed. Patients with FXIII deficiency in our series had more hematocrit drop and more transfusion requirements. We found no association with spontaneous bleeding. Alltough deficiency could be transient, treatment with FXIII concentrate could be useful to manage serious, persistent or life threatening bleedings. Disclosures No relevant conflicts of interest to declare.