STUDY OBJECTIVES: Heparin-induced thrombocytopenia (HIT) is an immune-mediated adverse drug reaction associated with a decrease of platelet counts that usually begins after at least 5 days of heparin treatment. Uncertainty exists about the risk of early onset of HIT (ie, < 5 days) in relation to previous heparin exposure. We therefore analyzed the temporal pattern of thrombocytopenia in patients with laboratory-confirmed HIT to assess whether patients with previous heparin exposure have an increased risk of early onset of HIT. DESIGN: Platelet count patterns in patients with a laboratory-confirmed diagnosis of HIT were examined in a retrospective chart review of a clinical study database. The onset of thrombocytopenia < 100 x 10(9)/L associated with the current heparin treatment (mainly unfractionated heparin) was analyzed using nonparametric maximum likelihood estimation. RESULTS: A total of 119 patients with 125 treatment episodes were assessed: HIT developed in 79 patients during initial exposure to heparin, and in 46 patients during reexposure. Early onset (< 5 days) of thrombocytopenia was associated with very recent heparin exposure. Patients reexposed to heparin within 3 months had an earlier onset of thrombocytopenia as compared to patients reexposed to heparin after 3 months (4.9 +/- 4.4 days vs 11.5 +/- 5.5 days [mean +/- SD], p = 0.001). There was no difference between onset on thrombocytopenia < 100 x 10(9)/L in patients reexposed to heparin within 3 to 12 months and after 1 year (9.7 +/- 6.4 days vs 12.3 +/- 5.2 days, p = 0.41). Whether platelet counts were obtained daily or less regularly did not affect the analysis. CONCLUSION: Early onset of thrombocytopenia in HIT is associated with recent heparin treatment (< 3 months). In contrast, for patients who did not receive heparin within the previous 3 months, HIT is an unlikely explanation for thrombocytopenia that occurs within the first 5 days.
STUDY OBJECTIVES:Heparin-induced thrombocytopenia (HIT) is an immune-mediated adverse drug reaction associated with a decrease of platelet counts that usually begins after at least 5 days of heparin treatment. Uncertainty exists about the risk of early onset of HIT (ie, < 5 days) in relation to previous heparin exposure. We therefore analyzed the temporal pattern of thrombocytopenia in patients with laboratory-confirmed HIT to assess whether patients with previous heparin exposure have an increased risk of early onset of HIT. DESIGN: Platelet count patterns in patients with a laboratory-confirmed diagnosis of HIT were examined in a retrospective chart review of a clinical study database. The onset of thrombocytopenia < 100 x 10(9)/L associated with the current heparin treatment (mainly unfractionated heparin) was analyzed using nonparametric maximum likelihood estimation. RESULTS: A total of 119 patients with 125 treatment episodes were assessed: HIT developed in 79 patients during initial exposure to heparin, and in 46 patients during reexposure. Early onset (< 5 days) of thrombocytopenia was associated with very recent heparin exposure. Patients reexposed to heparin within 3 months had an earlier onset of thrombocytopenia as compared to patients reexposed to heparin after 3 months (4.9 +/- 4.4 days vs 11.5 +/- 5.5 days [mean +/- SD], p = 0.001). There was no difference between onset on thrombocytopenia < 100 x 10(9)/L in patients reexposed to heparin within 3 to 12 months and after 1 year (9.7 +/- 6.4 days vs 12.3 +/- 5.2 days, p = 0.41). Whether platelet counts were obtained daily or less regularly did not affect the analysis. CONCLUSION: Early onset of thrombocytopenia in HIT is associated with recent heparin treatment (< 3 months). In contrast, for patients who did not receive heparin within the previous 3 months, HIT is an unlikely explanation for thrombocytopenia that occurs within the first 5 days.
Authors: Lori-Ann Linkins; Antonio L Dans; Lisa K Moores; Robert Bona; Bruce L Davidson; Sam Schulman; Mark Crowther Journal: Chest Date: 2012-02 Impact factor: 9.410
Authors: Z Sheng; H Zhao; H Yan; S Jiang; Y Guan; Y Zhang; L Song; C Liu; P Zhou; K Liu; J Liu; Y Tan Journal: Herz Date: 2017-07-19 Impact factor: 1.443
Authors: Linda Shore-Lesserson; Robert A Baker; Victor Ferraris; Philip E Greilich; David Fitzgerald; Philip Roman; John Hammon Journal: J Extra Corpor Technol Date: 2018-03
Authors: Adam Cuker; Gowthami M Arepally; Beng H Chong; Douglas B Cines; Andreas Greinacher; Yves Gruel; Lori A Linkins; Stephen B Rodner; Sixten Selleng; Theodore E Warkentin; Ashleigh Wex; Reem A Mustafa; Rebecca L Morgan; Nancy Santesso Journal: Blood Adv Date: 2018-11-27