Plasmapheresis in a child with the hemolytic-uremic syndrome.

Plasmapheresis, using fresh-frozen plasma for replacement, has been reported to be of benefit in the treatment of hemolytic-uremic syndrome and in thrombotic thrombocytopenic purpura. Both diseases have the same pathological characteristics and, possibly, the same pathogenesis. The mechanism by which plasma exchange results in clinical improvement is not clearly established, although recent reports indicate that it may be based on prostacyclin replacement rather than the removal of humoral factors toxic for platelets or vascular walls. Exchange plasmapheresis using an intermittent-flow cell processor with a disposable 100-ml pediatric centrifuge bowl is described in a 5-year-old girl with hemolytic-uremic syndrome.