Prognostic significance of computed tomography of the brain in thrombotic thrombocytopenic purpura.

We studied the prognostic value of computed tomography (CT) of the brain for neurologic morbidity in patients with thrombotic thrombocytopenic purpura. On review of Mayo Clinic records for 1975 through 1985, we found 32 patients with thrombotic thrombocytopenic purpura, 20 of whom had undergone CT of the brain during their hospitalization. Despite major neurologic symptoms and signs, normal CT findings were associated with complete neurologic recovery. Seventy percent of patients with normal results of CT of the brain recovered and had no neurologic deficits, whereas 80% of patients with CT abnormalities died or had permanent neurologic sequelae. A review of the literature supports these conclusions. Thus, we suggest that CT of the brain be done in any patient with thrombotic thrombocytopenic purpura and neurologic deficits. Regardless of the severity of neurologic involvement, normal CT findings should encourage continued vigorous treatment of the patient because a normal scan supports the possibility of full clinical recovery.