Posterior reversible encephalopathy syndrome with extensive cytotoxic edema after blood transfusion: a case report and literature review.

BACKGROUND: Posterior reversible encephalopathy syndrome (PRES) is described as a clinical-radiological disease entity with good prognosis. In brain MRI, PRES generally presents with vasogenic edema. Although PRES is induced by various causes, a small number of PRES cases have occurred after red cell blood transfusion. It is unclear whether there are characteristic features in PRES after blood transfusion.

CASE PRESENTATION: Here, we report a case of 75-year-old Japanese woman who had acute exacerbation of subacute anemia by bleeding from gastric ulcer. After receiving a red cell blood transfusion, she showed disturbance of consciousness with extensive cytotoxic and small vasogenic edema in the occipitoparietal area on brain MRI. She was diagnosed as PRES and suffered irreversible impairments of visual acuity and fields in both eyes. We summarized and discussed clinical features of cases with PRES after blood transfusion.

CONCLUSIONS: A total of 21 cases including the present one have been reported as PRES after blood transfusion. Of the cases, 20 of 21 were female, and 15 of 17 developed PRES in the course of chronic anemia lasting over 1 month. Anemia was severe in 15 of 20 cases, with hemoglobin levels < 3.5 g/dl. In 14 of 17 cases, hemoglobin levels increased to 5 g/dl by red cell blood transfusion until the onset of PRES. On brain MRI, 2 of 21 cases showed cytotoxic edema and 3 of 21 cases showed irreversible neurological disturbance. In this patient, the occurrence of PRES in subacute anemia and the presence of extensive cytotoxic brain edema with irreversible neurological deficits were characteristic points. When treating severe anemia, even with a subacute progression, we should consider a possibility that PRES occurs after blood transfusion with extensive cytotoxic brain edema and irreversible neurological changes.