Spontaneous Quadriceps Hematoma in an Elderly Adult Taking Therapeutic Doses of Warfarin

To the Editor: Oral anticoagulants are effective in preventing ischemic stroke and thromboembolism and have been shown to lower mortality in elderly adults with atrial fibrillation,1 but this needs to be balanced against the bleeding risks. This is a report of an unusual site of hemorrhage in an elderly adult taking therapeutic levels of anticoagulants. A 75-year-old woman was admitted to the hospital for an unrelated problem of hyponatremia. She had been taking warfarin for the past year after a left middle cerebral artery infarction and newly diagnosed atrial fibrillation. Her other medical conditions included hypertension, diabetes mellitus, and coronary artery bypass surgery. Her CHA2DS2-VASc (congestive heart failure, hypertension, aged ≥75, diabetes mellitus, stroke, vascular disease, aged 65–74, female sex) score of 8 placed her in the high-risk category for thromboembolic events.2 Her international normalized ratio (INR) had been maintained within the range of 2.54 to 3.08 in the months before her presentation. Two days after admission, her caregiver observed her to be in some discomfort. It was difficult to elicit a history because of expressive aphasia after her stroke. Her vital signs were normal, and there were no new neurological signs. A careful physical examination revealed her left hip to be slightly flexed, with an overlying tense anterior compartment of the thigh. Passive range of motion was painful. Her extremities appeared well perfused, and distal pulses were strong. Laboratory investigations showed an acute drop in hemoglobin from 12.1 g/dL on admission to 8.8 g/dL. Her platelet count was 212 × 109/L, and INR was 2.8. She was reassessed and found to have no obvious source of bleeding. There was no history of trauma. Magnetic resonance imaging of the lower limbs was performed and revealed a 14.0- by 5.0- by 2.5-cm intramuscular hematoma involving the left quadriceps femoris muscle (Figure 1). Associated edema was seen in the adjacent adductor muscles, obturator externus, piriformis, and iliopsoas muscles. The enlarged muscle bulk was seen abutting the neurovascular bundle, although no significant compression was seen. She was treated conservatively, and warfarin was discontinued. She was given fresh frozen plasma and a single unit of red blood cell transfusion and remained stable. Her INR dropped to 1.3, and she was discharged without oral anticoagulation. She remained well for 3 months after discharge and was started on aspirin. Spontaneous intramuscular bleeding in the thigh is rarely reported. The rectus sheath and the iliopsoas are more common sites of spontaneous bleeds while taking anticoagulants. Warfarin and unfractionated and low-molecular-weight heparin have all been implicated.3 Age is a known risk factor for spontaneous bleeding in the thigh while taking anticoagulants in the absence of trauma or preexisting coagulopathy. The case of an 80-year-old woman with spontaneous quadriceps intramuscular hematoma while taking warfarin was recently reported even though her INR was only 1.4 at the time of hemorrhage.4 Uncomplicated cases of quadriceps hematoma can be managed conservatively with reversal of anticoagulation, bed rest, cold compresses, and bandages.4 Needle aspiration has been successfully used to decompress hemorrhage in the lower extremity muscles.5 Compressive effects are the main cause of major complications. An expanding hematoma within the limited fascial space of the thigh can result in compartment syndrome. In such cases, surgical decompression and fasciotomy may be warranted.6 Timely diagnosis and treatment can prevent serious neurological and muscular dysfunction. In this instance, diagnosis was rendered more challenging in this aphasic woman who was unable to report pain, paraesthesia, or weakness. Signs of nerve compression are also more difficult to discern with preexisting neurological deficits. This underscores the need for careful physical examination and a high index of suspicion. Uncommon areas of hemorrhage should be considered if the source is not immediately apparent. This case also highlights the challenge with anticoagulation targets in elderly adults. This woman had significant bleeding while maintaining an INR of 2.5 to 3.0. At the “usual” INR target of 2.0 to 3.0, the frequency and severity of and mortality from stroke in atrial fibrillation is reduced.7 Joint guidelines by the American College of Cardiology, American Heart Association, and European Society of Cardiology suggest a target INR of 2.0 to 3.0 for high-risk individuals but propose a lower target range of 1.6 to 2.5 in individuals aged 75 and older.8 Anticoagulation targets should be individualized for elderly adults and take into account the greater risk of bleeding from older age, drug interactions, and comorbidities. Newer anticoagulants such as oral thrombin inhibitors are associated with greater extracranial major bleeding risk, and their safety profile remains to be established.9 Conflict of Interest: None. Author Contributions: Preparation of manuscript: Chew, Lim. Case management and critical review of manuscript: All authors. Sponsor's Role: None.