Endothelial specific isoform of type XVIII collagen (COL-18N): A marker of vascular integrity in haemophilic arthropathy.

Background: Haemophilic arthropathy (HA) is a major complication in haemophilia. Collagens IV, XV and XVIII are responsible for maintaining the integrity of the vessel wall in the joint. Following joint remodelling and damage, the short isoform of collagen type XVIII (COL-18N) is degraded, releasing measurable fragments.