- Paper Report
- Open Access
- Richard Venn1
© Biomed Central Ltd 2001
- Received: 2 July 2001
- Published: 4 December 2001
Heparin-induced thrombocytopenia (HIT) is a relatively common antibody-mediated drug reaction in the ICU and paradoxically is associated with thrombosis. Diagnosis is based on finding circulating heparin-dependent antibodies. Onset is usually about a week after the start of heparin therapy (typical-onset HIT), but it can occur more rapidly if the patient has previously been treated with heparin (rapid-onset HIT). This study identifies the timing of onset of HIT in relation to present and previous heparin treatment.
Of patients with typical-onset HIT, 28% (47/170) had received previous treatment with heparin. Typical-onset HIT usually began 5-10 days after starting heparin. All 73 patients with rapid-onset HIT had previously received heparin (within the last 100 days), and the median onset time was 10.5 h. There were no differences in outcome (thrombotic events or mortality) between the typical-onset and rapid-onset HIT groups. Heparin-dependent antibodies fell to undetectable levels at a median of 50-85 days during recovery from HIT. No new episodes of HIT occurred in seven patients with serologically confirmed HIT who received another course of heparin.
15-year retrospective review of medical and laboratory records in patients with serologically confirmed HIT.