Minimal factor XIII activity level to prevent major spontaneous bleeds

Abstract

Essentials: A strong association between bleeding severity and FXIII activity level (FXIII:C) was shown. The range 5-30 IU/dL of FXIII:C was associated with a high variability of bleeding severity. The PROspective study confirmed the association between FXIII:C activity and bleeding severity.A FXIII:C of 15 IU/dl is a proposed target to start prophylaxis for prevention of major bleeding. ABSTRACTBackground: Congenital factor XIII (FXIII) deficiency is a rare bleeding disorder

Minimal factor XIII activity level to prevent major spontaneous bleeds: comment

“…FXIII coagulant activity (FXIII:C) of 15 IU dL −1 was proposed as a cut‐off for this purpose. Surprisingly, in this study, ~ 50% of patients with FXIII:C between the lower detection limit and 29 IU dL −1 experienced these bleeds, and 36% of those with FXIII:C of ≥ 30% had minor spontaneous bleeding . These data are useful and helpful for better understanding the disorder and appropriate management of the disorder, but several issues should be considered.…”

“…Berichrom assay without a blank is one of the most commonly used FXIII:C assays that can overestimate FXIII:C by 2–15%, especially in severely affected patients . Although a very high correlation between local assay and central assay results was observed in 29 patients retested in the central laboratory, in this study, the type of assay used for almost half of the patients was not mentioned . Moreover, the type and duration of the prophylaxis replacement therapy and time of sampling can also affect the results of FXIII:C assays.…”

“…In a recent publication by Menegatti et al . on patients with congenital factor XIII deficiency, an effort was made to suggest a cut‐off for the start of prophylaxis in order to prevent spontaneous major bleeds, including central nervous system (CNS) bleeding, gastrointestinal bleeding, hematoma, and hemarthrosis (grade III bleeding according to the EN‐RBD classification) . FXIII coagulant activity (FXIII:C) of 15 IU dL −1 was proposed as a cut‐off for this purpose.…”

Fibrinogen and factor XIII: newly recognized roles in venous thrombus formation and composition

“…(31) These findings are consistent with clinical observations indicating that although patients with <4% FXIIIa activity have a significantly increased risk of bleeding, individuals with ≥30% FXIIIa activity, including those with acquired FXIII deficiency, are usually asymptomatic. (48) Thus, FXIII(a) antagonists may enjoy a wide therapeutic range and could be used alone or in concert with conventional anticoagulants. Moreover, association of FXIII impact on thrombus RBC retention and size with plasma, but not platelet, FXIII(31) may facilitate development of antagonists that would only need to inhibit the plasma compartment.…”

Minimal factor XIII activity level to prevent major spontaneous bleeds: reply

“…We thank Dorgalaleh et al . for their interest in our report regarding the minimal factor XIII activity level needed to prevent major spontaneous bleeding , and for describing their experience with low‐dose prophylaxis in patients with severe FXIII deficiency .…”