Fondaparinux sodium 2.5mg/0.5ml solution for injection pre-filled syringes

Fondaparinux, a synthetic pentasaccharide, represents the smallest heparin-based molecule and functions as a potent selective indirect inhibitor of activated factor Xa. Its high bioavailability, ease of dosing, and favorable tolerability profile render it an ideal antithrombotic agent for pregnant patients who are intolerant to unfractionated heparin (UFH) and low-molecular-weight heparins (LMWHs). Recent studies have highlighted the advancements in the use of fondaparinux in pregnant patients over the past decades. This research provides a comprehensive summary of the safety profiles of fondaparinux, noting that its application in pregnant women may elevate the risk of bleeding events during pregnancy and postpartum. Caution is advised when administering fondaparinux to patients with renal insufficiency. The advantages of fondaparinux include a lower risk of thrombocytopenia, liver injury, allergic reactions, and osteopenia compared with UFH and LMWHs. Although fondaparinux can cross the placental barrier and be detected in the umbilical-cord blood, real-world data have not established a direct association between fondaparinux and teratogenicity or adverse fetal outcomes. Overall, fondaparinux appears to be a viable option for certain groups of pregnant patients requiring anticoagulation. However, further research is warranted to provide deeper insights into the benefits and risks associated with fondaparinux use in this population. The long-term effects of intrauterine exposure to fondaparinux remain an important area for future investigation.

Abstract licence: CC BY-NC-ND

Heparin-induced thrombocytopenia (HIT), a prothrombotic disorder caused by heparin-dependent antibodies, is often treated with fondaparinux, generally yielding positive outcomes. A 69-year-old male with a history of stage IIIb small cell lung cancer developed severe HIT (platelet count nadir, 11 × 10⁹/L) after receiving heparin for stroke prophylaxis, complicated by deep vein thrombosis (DVT) and acute limb ischemia (ALI). Despite treatment with fondaparinux, thrombocytopenia secondary to HIT persisted, and his arterial thrombosis progressed, leading to urgent angioplasty and thrombectomy. This clinical course raised concerns for autoimmune HIT (aHIT) refractory to fondaparinux or potential fondaparinux cross-reactivity. The patient was transitioned to argatroban postoperatively, resulting in rapid platelet recovery and clinical improvement. Our case highlights the limitations of fondaparinux in select HIT cases, particularly when aHIT is suspected, and underscores the need for vigilance in monitoring for treatment failure. This report adds to emerging data on alternative anticoagulation strategies for refractory HIT, including the potential role of direct thrombin inhibitors in severe cases.

Abstract licence: CC BY

Septic thrombophlebitis of the internal jugular vein (IJV), known as Lemierre's syndrome, is a rare complication secondary to infections in the head and neck. Cholesteatoma of the middle ear complicated with Lemierre's syndrome is rarely observed in clinical practice. Currently, the treatment controversy centers on whether anticoagulation therapy is necessary for IJV and distant metastatic emboli induced by Lemierre's syndrome. A 46-year-old female patient with middle ear cholesteatoma underwent modified radical mastoidectomy and tympanoplasty surgery and complicated with Lemierre's syndrome, presenting with intermittent high fever, chills, headache, and left lateral neck pain. Computed tomography (CT) revealed thrombosis and internal gas in the left IJV, while blood culture and blood pathogenic microorganism metagenomic detection were negative. We administered sodium ceftriaxone (1 g every 12 hours) for 3 days. According to the secretion culture results showing 90% Actinomyces europaeus and 10% Corynebacterium without mycolic acid, penicillin (2.4 million IU) was added intravenously every 6 hours. The patient's infection worsened on the first day after surgery. We adjusted to upgrade anti-infection vancomycin 1 g every 12 hours, combined with meropenem (1 g every 8 hours) and metronidazole (0.5 g) every 8 hours for 4 weeks, and subcutaneous injection of enoxaparin 0.4 mL every 12 hours for 1 week, then adjusted to rivaroxaban tablets (15 mg bid). Amoxicillin-clavulanate for 2 weeks and rivaroxaban 10 mg were administered orally for 3 months after discharge. A follow-up neck CT scan with intravenous contrast suggested that the gas in the left IJV had disappeared, but the thrombus persisted. During the 3 month follow-up, the patient's vital signs, blood routine, and D-dimer levels were within the normal range. The surgical area healed well, and the patient reported no discomfort. Lemierre's syndrome represents a potentially-fatal complication that results in considerable mortality and must be identified early and aggressively treated.

Abstract licence: CC BY-NC