Safety of low-dose low-molecular-weight-heparins in thrombocytopenic stem cell transplantation patients: a case series and review of the literature

Abstract

Summary:Few attempts have been made to examine the feasibility of safely administering low-molecular-weight-heparins (LMWHs) in the presence of concurrent thrombocytopenia. We retrospectively investigated the safety of lowdose LMWH in BMT patients, a population at risk of bleeding. In total, 26 patients received at least one dose of low-dose enoxaparin (ie o1 mg/kg/day) during thrombocytopenia. s.c. enoxaparin 40 mg once daily was given in 85% of the cohort. The mean number of platelet days o55 Â 10 9 and o20 Â 10 9 /l were 16.5 days (95% CI ¼ 8.04-24.96) and 4.14 days (95% CI ¼ 2.35-5.93), respectively. The mean number of low-dose enoxaparin administration days when platelet o55 Â 10 9 and 20 Â 10 9 /l were 9.89 days (95% CI ¼ 3.26-16.53) and 2.25 days (95% CI ¼ 0.57-3.93), respectively. Minor bleeding occurred in four patients (15%) whereas major episodes developed in two patients (8%). The latter two events occurred during the transition between full therapeutic (ie 1.5-2 mg/kg/day) and low-dose enoxaparin close to the onset of thrombocytopenia. The present case series, along with the discussed literature, descriptively suggests that low-dose enoxaparin may be safely administered at a platelet count in the range of 20 and 55 Â 10 9 /l in BMT patients who weigh 455 kg.

Management of venous thromboembolism during thrombocytopenia after autologous hematopoietic cell transplantation

“…The lack of association between platelet threshold and risk of bleeding among anticoagulated patients in our analysis is consistent with a previously published retrospective case series, where a total of 31 patients receiving enoxaparin appeared to be safe with a platelet range of 22 to 55 3 10 3 /mL post-HCT. 10,17 If the relative safety of a lower platelet transfusion threshold (30 vs 50 3 10 3 /mL) can be confirmed in a prospective setting, a change in clinical practice could lead to fewer transfusions, conservation of donated platelets, and reduced cost. The strengths of our study include a large patient population, uniform inclusion criteria, similar duration of thrombocytopenia with consecutive platelet values, and excellent short-term follow-up.…”

“…7 Several retrospective case series attempted to address the efficacy and safety of anticoagulation in thrombocytopenic cancer and transplant patients. [8][9][10] However, all reports are limited by the small sample size (N , 100), heterogeneous inclusion criteria, and variable duration and severity of thrombocytopenia. With these limitations in mind, we designed the current study using a large cohort of autologous HCT patients to explore antithrombotic management in patients on active anticoagulation for VTE.…”

Thrombosis in Multiple Myeloma

“…5 Furthermore, LMWH has been used without major bleeding risks in patients with thrombocytopenia after stem-cell transplantation, and is thus an alternative agent. 36 …”

Between Scylla and Charybdis: antithrombotic therapy in hematopoietic progenitor cell transplant patients

“…10 This is based on the excess bleeding rates seen in thrombocytopenic patients with hemophilia and in some case series involving transplant patients. 11,12 In theory, one can give platelet transfusions to patients to try to keep the platelet levels above these thresholds, but in practice this can be difficult and in my experience it can be associated with excess bleeding.…”