Reduced factor XIII activity Factor XIII subunit B deficiency 2016-01-21T17:03:48Z Reduced factor XIII, subunit B Deficiency of factor XIII subunit B, leading to a reduced factor XIII activity. Activated Factor XIII cross-links fibrin polymers solidifying the clot. UMLS:C2750481 Measurement of subunit A or B can be performed by Elisa kits. Adding the more granular term would facilitate mutation analysis as both subunits are encoded by different genes. This is not always performed in the diagnostic workup so 'Reduced factor XIII activity' would sufice. This term has been requested and created by members of the BRIDGE consortium