['Hemorrhagic complications are commonly encountered in patients with end-stage renal disease (ESRD). Uremic patients show a bleeding diathesis mainly due to abnormalities in platelet function. There are several tests to detect and measure impairment of hemostasis in these patients, but none appear to be ideal. In recent years, the PFA-100 (platelet function analyzer) was introduced to measure primary, platelet-dependent hemostasis. In this study, the effect of hemodialysis on platelet function was evaluated using the PFA-100 in patients with ESRD.', 'The study was performed on 45 patients with ESRD undergoing regular hemodialysis aged between 20-76 years (median: 54 years). Collagen/epinephrine (CEPI) and collagen/ADP (CADP) closure times were measured before and after the hemodialysis session using the PFA.', 'CEPI (normal range: 85-165 sec) was significantly shortened from 230+/-60 to 206+/-63 sec after hemodialysis (p<0.05). The CADP (normal range: 71-118 sec) was also shortened by hemodialysis from 177+/-69 to 169+/-71 sec (p>0.05). CEPI closure times of 10 (26%) in 38 patients with long CT returned to normal after hemodialysis. CADP closure times of 9 (25%) of 36 patients with long CT returned to normal after hemodialysis.'] Does hemodialysis shorten long in vitro closure times as measured by the PFA-100?