Multigene panel analysis of connective tissue and vascular genes in patients with a bleeding disorder of unknown cause or a cerebrovascular event.

In the bleeding disorder of unknown cause cohort ( n = 69), 61% were children (median age, 13 years) and 61% were female; 75% had a positive International Society on Thrombosis and Hemostasis Bleeding Assessment Tool score, and 54% had a positive family history.

Mucocutaneous bleeding was most common, and 36% had surgery-related bleeding.

Diagnostic yield, including variants of uncertain significance, was 15%, with (likely) pathogenic variants in ENG and COL5A1 ; no significant genotype-phenotype associations were found.