The incidence of heparin-induced thrombocytopenia in patients treated with low molecular weight heparin for superficial vein thrombosis.

Abstract

BACKGROUND:

The risk of heparin induced thrombocytopenia (HIT) associated with low molecular weight heparin (LMWH) for treatment of superficial vein thrombosis (SVT) is uncertain. As a result the necessity of platelet count monitoring is unclear in this setting.

AIMS:

To assess the risk of HIT in outpatients treated with LMWH for SVT.

METHODS:

In a prospective single centre study we included all symptomatic outpatients in whom a real-time B-mode and color Doppler ultrasonography examination revealed SVT without DVT. Patients treated with vitamin K antagonists or fondaparinux were excluded. Patients received full dose enoxaparin for 1week followed by half therapeutic dose for 3weeks or parnaparin 8500UI aXa for 10days followed by 6400UI aXa once daily for 20days. Platelet count was performed on the day of diagnosis (D0) and 7 (D7), and 14 (D14) days afterward. Primary outcomes were the rate of thromboembolic events and of HIT during a 3-month follow-up.

RESULTS:

678 outpatients (age: 64.7±16.2years, male: 42.0%) were evaluated. During follow-up, 7 venous thrombo-embolic events were recorded (1.03% CI 95%: 0.50-2.11%), while no major bleeding was observed (0.0% CI 95%: 0.0-0.56%). Platelet count was 255±93×10(9)/L at D0, 245±93×10(9)/L at D7 (p=0.204 vs. D0) and 261±116×10(9)/L at D14 (p=0.405 vs. D0). No fall in platelet count>50% and no case of HIT were recorded (HR 0.0% CI 95%: 0-0.56%).

CONCLUSIONS:

A 4-week LMWH treatment for SVT is associated with an incidence of HIT lower than 0.6% and platelet count monitoring may be omitted in this setting.

• Authors: Michelangelo Sartori, Elisabetta Favaretto, Ludovica Migliaccio, Giuliana Guazzaloca, Cristina Legnani, Gualtiero Palareti, Benilde Cosmi
• Journal: Thrombosis research (Thromb Res) Vol. 139 Pg. 154-7 (Mar 2016) ISSN: 1879-2472 [Electronic] United States
• PMID: 26916314 (Publication Type: Journal Article)
• Copyright: Copyright © 2016 Elsevier Ltd. All rights reserved.

Chemical References

• Anticoagulants
• Heparin, Low-Molecular-Weight

Topics

• Aged
• Aged, 80 and over
• Anticoagulants (adverse effects, therapeutic use)
• Female
• Heparin, Low-Molecular-Weight (adverse effects, therapeutic use)
• Humans
• Incidence
• Male
• Middle Aged
• Platelet Count
• Prospective Studies
• Thrombocytopenia (chemically induced, epidemiology)
• Venous Thrombosis (drug therapy)