Spontaneous Neck Hematoma in a Patient with Fibromuscular Dysplasia: A Case Report and a Review of the Literature

Background. Fibromuscular dysplasia (FMD) is a vascular disease that may present as aneurysms in the cervical arteries. Spontaneous neck hematoma is a rare life threatening medical condition. This is the first report of neck hematoma in a patient with FMD. Methods and Results. We present a case of a 69-year-old woman, with diagnosed cervical FMD and a 3-day history of sore throat and neck pain, who presented with enlarging neck hematoma. No active bleeding was noticed on CT angiography, airway was not compromised, and patient was managed conservatively. Next day, invasive angiography was performed, and no bleeding vessel was demonstrated. Patient has improved and was discharged after 5 days of hospitalization. We have discussed the different etiology of this condition, focusing on systemic vascular diseases. Conclusion. Complaint of neck pain in a patient with a FMD should raise suspicion for possible neck hematoma. Conversely, spontaneous neck hematoma without clear etiology should raise suspicion for a systemic vascular disease. 1. Introduction Spontaneous neck hematoma is a rare medical condition which may be life threatening [1–5]. The literature regarding the subject is based solely on case reports. The classic symptoms of cervical hematoma are tracheal and esophageal compression, tracheal displacement, and subsequent appearance of subcutaneous bruising or swelling in the neck, known as the Capps triad [1, 2, 6]. Other symptoms such as dysphagia, hoarseness, and pain have also been described [1, 7]. The etiology of nontraumatic spontaneous neck hematoma includes rupture of aneurysms [1, 8, 9], rupture of parathyroid adenoma [3, 4, 7], infection [10], and an underlying coagulopathy [11]. Fibromuscular dysplasia (FMD) is a noninflammatory, nonatherosclerotic vascular disease that involves small and medium-sized arteries [12, 13]. Its pathogenesis is idiopathic and involves true proliferation of smooth muscle cells and fibrous tissue [14]. The diagnosis of FMD is established by histopathology or angiography [12–15]. The classic angiographic pattern is that of irregular caliber with alternating segments of narrowing and dilatation, also known as the “strings of beads” sign, which has been observed in over 80% of the cases [12, 14, 15]. FMD most commonly involves the renal (60%) and cervicocephalic arteries (30%) [13, 14]. The latter could result in an ischemic or hemorrhagic stroke and cervical artery dissection and could be associated with intracerebral aneurysms [12, 14, 15]. The prevalence of symptomatic cervicocephalic FMD is estimated to be 0.002%