Hemorrhage of a Cavernous Hemangioma of the Brainstem Presenting with Fever of Unknown Origin: A Case Report.

BACKGROUND Cavernous malformations (CMs) or hemangiomas are benign vascular hamartomas of the central nervous system (CNS) that constitute 5-15% of all CNS vascular malformations. Most patients with brainstem CMs present with a sudden onset of seizures, intracranial hemorrhage, cranial nerve deficits, headache, or ataxia. Up to 20% to 50% of patients are asymptomatic, and their CMs are diagnosed incidentally on brain magnetic resonance imaging. CASE REPORT We present a case of a 42-year-old man with a brainstem cavernous hemangioma presenting with fever of unknown origin and mild headache without meningismus. The patient underwent a midline suboccipital craniectomy and removal of a ruptured brainstem cavernous hemangioma and the surrounding thrombus. Postoperatively, the patient developed left facial nerve palsy, left abducens nerve palsy, and xerostomia. Abducens palsy and xerostomia resolved spontaneously days after the operation. At the 6-month follow-up, the patient showed stable improvement with resolution of his neurological deficits. CONCLUSIONS To our knowledge, there is no reported case of a patient with a ruptured brainstem cavernoma presenting with fever of unknown origin as the main symptom. We assume that the minimal intraventricular hemorrhage triggered the hypothalamic thermoregulating mechanism. Thus, it would be useful for physicians to raise the suspicion of a ruptured brainstem cavernous malformation with further imaging evaluation when investigating fever of unknown origin.