A 36-year-old woman presented with abdominal pain followed by fever, confusion, right sided weakness and nuchal rigidity. The investigation showed severe anemia, thrombocytopenia and left middle cerebral artery (MCA) territory infarction. The platelet was given before the lumbar puncture. After that, the patient’s clinical was deteriorating to quadriplegia and stuporous. Then the patient was referred to Siriraj Hospital. The patient was diagnosed thrombotic thrombocytopenic purpura (TTP) following pentad of clinical features: microangiopathic hemolytic anemia, thrombocytopenia, fever, neurologic, and renal abnormalities. Magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) of brain showed extensive bilateral MCA and mid basilar artery stenosis. That was uncommon findings in TTP. The authors believed that platelet transfusion made the clinical deterioration and develop extensive intracranial vessels stenosis. Even the plasma exchange was performed but the neurological symptoms did not improved. Finally, the patient succumbed from ventilator associated pneumonia at 2 months after diagnosis.

Keyword: Middle cerebral artery infarction, Thrombotic thrombocytopenic purpura, TTP, Platelet transfusion