Preparation of leukocyte-poor platelets by filtration

There is evidence that leukocyte contaminating red blood cells and platelet concentrates are responsible for refractoriness to platelet transfusions. The efficacy of a cotton-wool filter to remove leukocytes from red blood cells has been documented previously. The present study was designed to evaluate whether the cotton-wool filters can effectively remove leukocytes from platelet concentrates. Sixty pools of random-donor platelets and single-donor plateletpheresis products were filtered through a cotton-wool filter. The efficacy of filtration was determined by measuring the absolute numbers of leukocytes and platelets and subpopulations of mononuclear cells. The average platelet loss was 8% per pool of random platelets and 10% per plateletpheresis product. The average leukocyte removal was 99% from a pool of random platelets and plateletpheresis concentrates collected by CS-3000 and 90% from plateletpheresis concentrates harvested by single-stage COBE/IBM-2997. The filtration removed 100% of granulocytes, 95% of monocytes, 90% of B-lymphocytes, and 85% of T-lymphocytes. We conclude that filtration through a cotton-wool filter is an efficient and cost-effective method for preparation of leukocyte-poor platelets.     

Alice in Wonderland syndrome as a presenting symptom of EBV infection

Four Chinese patients (2 boys, 2 girls), ages 4–9 years, who had episodes of perception error of body schema and objects are reported. The metamorphopsia, which had been named Alice in Wonderland syndrome, is the major presentation. All of them were proved to have acute Epstein-Barr virus infection, as documented by positive heterophil antibody test and/or positive IgM antibody to Epstein-Barr virus capsid antigen. The duration of the perception disorder ranged from 1 week to 3 months. We believe that any young child presenting with Alice in Wonderland syndrome should undergo examination for Epstein-Barr virus infection; complete recovery from the disorder can be expected.