Fondaparinux-sodium
Bullous haemorrhagic dermatosis: case reportA 90-year-old woman developed bullous haemorrhagic dermatosis during anticoagulant therapy with fondaparinux sodium for stroke prophylaxis.The woman was admitted to hospital with hypoxia secondary to pulmonary oedema and ongoing unspecified antibacterials [antibiotics] for infected hip prosthesis. She had history of atrial fibrillation, heparin-induced thrombocytopenia following administration dalteparin sodium [dalteparin] and lower gastrointestinal bleeding related to diverticular disease. Four weeks prior to the admission, right hip hardware was removed and revision to a cemented right hip hemiarthroplasty was performed due to methicillin-sensitive Staphylococcus aureus infection. At the admission, she was receiving 6-week course of cefalexin [cephalexin] and rifampicin [rifampin]. Prior to the admission, she had received apixaban for stroke prophylaxis but, apixaban was switched to warfarin due to its interaction with rifampicin. After admission, given the interaction between warfarin and rifampin, and her complex history of thrombosis, she started receiving anticoagulant therapy with fondaparinux sodium [fondaparinux; dose not stated] injection daily into the abdomen while continuing rifampicin. The dyspnoea resolved with furosemide. On day 4 after the fondaparinux sodium initiation, she developed deep purple haemorrhagic lesions and bullae on the left forearm. Over the following 2 days, the lesions progressed in size and number. Eventually, the right arm was affected. On day 6 of the fondaparinux sodium initiation, the left epicondylar bullae ruptured and resulted in substantial haemorrhage. Haemoglobin decreased from 91 g/L on day 4 of the fondaparinux sodium initiation to 70 g/L on day 6. Coagulation parameters tests revealed the following: INR 1.2, prothrombin time 14.9 seconds and partial thromboplastin time 41 seconds.The woman received 4 units of packed red blood cells over 3 days due to haemodynamic instability. On day 7 of the fondaparinux sodium initiation, fondaparinux sodium was discontinued due to ongoing bleeding. The skin lesions were dressed with tranexamic acid-soaked compression dressings. Her medication review did not show other potential causes of haemorrhagic bullae. On day 6 of the fondaparinux sodium initiation, rheumatologic panels showed positive extractable antibody panel and anti-Ro/SSA52, raising suspicion of vasculitis-related haemorrhagic bullae. However, vasculitis-related haemorrhagic bullae was ruled out based on findings of punch biopsy from the left arm taken on day 10. Then, she was diagnosed with fondaparinux-induced bullous haemorrhagic dermatosis. The rifampicin was discontinued and low-dose apixaban was restarted for stroke prophylaxis. On day 23, the haemorrhagic bullae completely resolved with involution of the skin discoloration and desiccation of the bullae.
