Early-onset heparin-induced thrombocytopenia after a 165-day heparin-free interval: case report and review of the literature.
Early- or abrupt-onset immune-mediated heparin-induced thrombocytopenia (HIT) is defined as HIT that occurs less than 5 days after exposure to heparin in patients who have received heparin within the previous 100 days. We identified no reports in the literature of early-onset HIT in patients who had a heparin-free interval longer than 100 days. However, we report a case of early-onset immune-mediated HIT illustrated by a positive HIT result with serotonin release and enzyme-linked immunosorbent assays, and a decrease in platelet count to less than 100 x 10(3)/mm3 with no evidence of thrombosis, approximately 165 days after the patient's last exposure to heparin. We conclude that clinicians should choose alternative forms of anticoagulation in patients with even a remote history of HIT. If clinicians are compelled to reexpose patients to heparin, they should confirm a negative HIT assay result, monitor for clinical signs of HIT, and provide appropriate treatment if HIT is suspected.
Temple University School of Pharmacy, 3307 North Broad Street, Philadelphia, PA 19140, USA. ddeeugen@temple.edu
Deborah L
DL
DeEugenio
Nicholas J
NJ
Ruggiero
Lynda J
LJ
Thomson
L Bernardo
LB
Menajovsky
Jay H
JH
Herman
D000368:Aged; D000925:Anticoagulants / Q000009:adverse effects*; D017984:Enoxaparin / Q000009:adverse effects*; D006801:Humans; D008297:Male; D013921:Thrombocytopenia / Q000139:chemically induced*; D013997:Time Factors
D000925:Anticoagulants; D017984:Enoxaparin