As described in our previous study, platelet-rich cryoprecipitate and thrombin were obtained from 300-400ml whole blood of each patient enrolled in the PRFG group and then frozen at -20°C for storage. Prior to application, frozen cryoprecipitate and thrombin stored were thawed in a 37°C water bath. Aminomethylbenzoic Acid (1ml: 1mg, Sigma-Aldrich, St Louis, MO) was added into the cryoprecipitate in the volume ratio of 1:10.

Patients in this group only received standard of care when their fistula output < 200ml/24h.

Commercial FG (Zhejiang Puji Porcine fibrin sealant) was applied to close fistulas.

A forward-viewing fistula-fiberscope (EndoView, Outai Medical Equipment, Shanghai, China), with 15cm length and 5mm width of fiber optical wire, was inserted into the fistula tract to accomplish endoscopic visualization. Briefly, the fistula-fiberscope assisted procedure was carried out percutaneously, allowing the exposure of internal hole and the whole tracts, followed by insertion of this catheter with distal mixing device.

The fraction of patients with complete closure of fistula during 14 days

Incidence of adverse events and severe adverse events up to 180 days (defined as an event that was fatal or life-threatening, led to additional hospitalization or disability, or required an intervention to prevent one of these outcomes)

Hospital cost upon enrollment, Hospital cost during entire hospital stay, Cost between fistula onset and final outcome