RESUMEN
Objective: To correlate the incidence of hemorrhage and thrombosis to bleeding time (BT) and platelet aggregation in 27 consecutive patients with myeloproliferative diseases (MPD). Design: Retrospective study. Setting: Public tertiary referral center. Patients: Eighteen patients with chronic myelogenous leukemia (CML), 5 with polycytemia vera (PV), 2 with essential thrombocytemia (ET) and 2 with idiopathic myelofibrosis (MF). Duke's BT and epinephrine-induced platelet aggregation were performed on the patients and on 10 healthy individuals. Results: Eleven patients presented symptoms (41 percent): 9 with hemorrhage (33 percent) and 5 with thrombosis (19 percent). There were less symptomatic patients in the CML group (28 percent) than in the other MPD (67 percent), without statistical significance (Fisher, p=0.06). Duke's BT was longer in symptomatic patients (Mann-Whitney, p<0.05). Platelet aggregation was abnormal in 7 patients (26 percent) and 71 percent of them were symptomatic (Fisher, p=0.07) Conclusions: The high incidence of bleeding and thrombosis in patients with MPD was related to prolonged BT, but not to platelet aggregation abnormalities.