Severe haemorrhages leading to a diagnosis of rare bleeding disorder occur at a very young age: A study from the FranceCoag network.

These data support that any unusual SH should raise a suspicion of IRBD. Particularly before 1-year of age, it is suggested to first confirm moderate or severe haemophilia and severe IRBD by standard coagulation tests (APTT, PT and fibrinogen), combined with a clotting FXIII assay as first-line investigation. Subsequent assays of coagulation factors should be performed in the case of abnormal values, in second-line investigation.