Bullous hemorrhagic dermatosis probably associated with enoxaparin

In July 2014, a 52-year-old man with a history of human immunodeficiency virus infection, hypertension, hypercholesterolemia and cirrhosis as a complication of hepatitis C was, in addition, diagnosed to have a multicentric hepatocellular carcinoma with brain metastases and venous thrombosis of the left sigmoid sinus and the left internal jugular vein. He was started immediately on enoxaparin, 100 IU/kg twice daily by subcutaneous injections. His other medications included enalapril, simvastatin and a combination of antiretroviral drugs (emtricitabine, tenofovir and efavirenz). Palliative chemotherapy was delayed until resolution of venous thrombosis. After a week of treatment with enoxaparin, the patient complained of non-pruritic hemorrhagic blisters on both arms and the left leg. He denied taking any other new medication and application of any topical product. Physical examination revealed five hemorrhagic tense blisters on both the arms and the left leg on otherwise normal skin [Figure 1]. The mucosae were clinically normal. No lesions were detected at the enoxaparin injection sites. A coagulation profile and platelet count were normal. Skin biopsy revealed intraepidermal blisters containg red blood cells. No inflammatory infiltrate or signs of vasculitis were observed [Figure 2]. Direct immunofluorescence did not showed any immunoreactants. A diagnosis of bullous hemorrhagic dermatosis, probably in association with enoxaparin subcutaneous injection, was made. Our differential diagnoses included porphyria cutanea tarda, bullous pemphigoid and acquired bullous epidermolysis; however, normal blood tests, direct immunofluorescence test and the histopathology ruled out these diagnoses. We excluded the others drugs (enalapril, simvastatin and antiretroviral drugs) because the patient had been taking them for many years, the only new drug was enoxaparin. The lesions resolved within days, despite continuation of treatment.