A Portuguese patient homozygous for the -25G>A mutation of the HAMP promoter shows evidence of steady-state transcription but fails to up-regulate hepcidin levels by iron

patients with thrombosis tested antibody positive, compared with 26 (6.1%) of 425 patients without thrombosis (odds ratio [OR], 15.3 [95% CI, 2.94-25.23];P ϭ .005).This supports previous suggestions 6 that formation of platelet-activating HIT antibodies can be associated with thrombosis even in the absence of a significant platelet count fall.Second, among the 87.7% of study patients who underwent serologic testing for HIT antibodies, there was approximately a 60% lower seroconversion rate with LMWH compared with UFH (55.6% and 64.7% by the platelet activation assay and immunoassay, respectively).Nevertheless, despite this moderate reduction in frequency of HIT antibody formation, there was complete avoidance of clinical HIT using LMWH (0 versus 12 cases).This underscores the importance of considering HIT to be a largely preventable adverse drug reaction, at least in postorthopedic surgery patients.