Factor-XIII activity in patients with mild to moderate ulcerative colitis and active bleeding: a prospective observational study.

Plasma activity of FXIIIa did not show any significant differences during the UC course. FXIIIa was measured below normal range < 70% in only 8 patients during the flare and increased to normal values during follow-up in 7 of these patients. Low FXIIIa during the flare was not associated with an increased bleeding activity. In patients with a mild to moderate UC flare and prolonged bleeding, FXIIIa activity is neither predictive of UC severity nor of any bleeding activity in an outpatient setting. Trial registration This non interventional, non pharmacological prospective study was not obligated to receive a unique identifying number. This trial is registered with the Ethics Committee of the State Medical Chamber of Saxony, Dresden, Germany (Clinical Trials Registry number EK-BR-03/14-1).