Comparison of outcomes in autoimmune acquired factor XIII deficiency with and without underlying diseases: a systematic review.

Autoimmune acquired factor XIII deficiency (AiF13D) is an exceptionally rare and serious bleeding disorder. This condition may occur idiopathically or in association with comorbidities, such as malignancies or autoimmune diseases. Data comparing these distinct etiological subgroups remain limited. Therefore, we conducted a systematic literature review of published case reports, case series, and cohort studies on AiF13D indexed in PubMed, Web of Science, and Scopus up to December 2023. We compared the clinical characteristics, treatment modalities, and outcomes between patients with AiF13D associated with underlying disorders and those with idiopathic AiF13D. Our analysis revealed a higher proportion of female patients in the AiF13D group with underlying diseases compared to the idiopathic group. Statistically significant differences were observed that patients with underlying diseases exhibited slightly higher inhibitor levels and a greater frequency of Grade III bleeding events. Furthermore, fewer AiF13D patients with underlying diseases received combination therapy (prednisone plus rituximab or cyclophosphamide) compared to the idiopathic group. Additionally, this group experienced higher rates of relapse and/or mortality. Collectively, these findings indicated that AiF13D patients with underlying diseases experience more severe bleeding manifestations and poorer outcomes. Consequently, clinicians managing concomitant conditions should maintain vigilance for potential AiF13D development. Regular monitoring of FXIII activity and inhibitor titers is essential, coupled with prompt initiation of anti-inhibitor therapy when indicated.