A 48-year-old African American woman was brought to the emergency department by ambulance for evaluation of acute onset of altered mental status and neurological deficits. She was found leaning over the side of her bathtub with aphasia, left-sided facial droop, and left hemiparesis, suggestive of a stroke. Prior to this event, she was able to walk and perform daily activities. At baseline, she had mild dysarthria, minimal expressive aphasia, and right upper extremity weakness and spasticity. These were residual neurological deficits from the cerebrovascular accident (CVA) she had 6 years ago. Her past medical history included ischemic strokes 8 years ago associated with post-CVA seizures, another ischemic stroke 6 years ago, and thrombotic thrombocytopenic purpura (TTP). On physical examination, she appeared lethargic, disoriented to person, place, and time; she was unable to name objects or repeat words; and she was unable to follow commands. She was found to have a left facial droop, partial right-sided gaze preference, left hemianopia, and spastic left hemiparesis. A CT scan of the head without contrast showed two previous middle cerebral artery (MCA) territory cerebral infarctions with an acute right MCA occlusion at the origin of the M2 segment. An additional thrombus was present in a branch of the right MCA along the distribution of the posterior insular cortex. An MRI of her brain revealed a large area of acute ischemia within the distribution of the anterior division of right MCA, small foci of petechial hemorrhage in the right insula around the area of ischemia, and small foci of acute ischemia in the right cerebellar hemisphere. A CT angiogram confirmed these findings.This patient presented with acute stroke involving the distribution of the right MCA. Her vital signs on admission were within normal limits. Given that her clinical presentation was indicative of a stroke and having arrived within 3 hr of the onset of her symptoms, she was given pharmaceutical tissue plasminogen activator (tPA). Intra-arterial thrombolysis and thrombectomy were performed; however, her neurological symptoms did not improve.Her family history was negative for premature strokes or thrombotic disorders. The patient did not smoke, drink alcohol, or use illicit drugs. Her home medications included Keppra and Dilantin for seizure prophylaxis. A transesophageal echocardiogram performed on admission was unremarkable. Her lipid profile and HgbA1c were within normal limits. Admission laboratory data included hemoglobin (Hgb) 13.2 g/dl, hematocrit (Hct) 38.6%, and platelet (PLT) count of 113,000 per cubic mm of whole blood. Other laboratory values included lactate dehydrogenase (LDH) 238 U/l (normal range, 98-192 U/l), reticulocyte count 1.6%, international normalized ratio (INR) 1.22, prothrombin time (PT) 15.6 sec, activated partial thromboplastin time (aPTT) 26.7 sec, blood urea nitrogen (BUN) 6 mg/dl, and serum creatinine 0.8 mg/dl. Peripheral blood smear (PBS) did not show schistocytes. Patient's neurological deficits and alter...