Impact of prefilter dilution on IgG removal in membrane-based therapeutic plasma exchange.

INTRODUCTION: Previous studies have demonstrated that a "one plasma volume exchange" would result in an estimated 63% decline in pretreatment IgG levels. We evaluated the use of prefilter dilution with normal saline as a method to prevent filter failure without decreasing the efficiency of IgG removal. METHODS: Twenty-one treatment sessions were analyzed and all received prefilter dilution with normal saline. Primary outcome was to determine whether prefilter dilution resulted in decreased treatment efficiency in removing the targeted IgG. Secondary outcome was filter failure in conjunction with the combined use of prefilter heparin and saline infusions. RESULTS: All 21 treatments (100%) received prefilter dilution with saline solution and 19/21 (90.47%) also received prefilter heparin (bolus and/or hourly infusion). We demonstrated a 60%-70% decline in pretreatment IgG levels. CONCLUSION: Prefilter dilution during membrane-based therapeutic plasma exchange based treatment did not result in a demonstrable decrease in efficiency of IgG removal while maintaining filter patency.

Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis in a postpartum patient with preeclampsia: a case report.

Hemophagocytic lymphohystiocytosis is an extremely life-threatening immune deregulatory syndrome. It is characterized by pathologic activation of immune cells, leading to excessive cytokine production, multiorgan failure, and potentially, death. A 28-year-old primigravida at 32 weeks and 3 days of gestation presented with newly-diagnosed preeclampsia with severe features, fever, and fetal tachycardia. She was delivered by cesarean delivery. After delivery, she had a fever of unknown origin, with evidence of a hyperinflammatory state. Extensive infectious work-up was significant for positive Epstein-Barr Virus. A bone marrow biopsy demonstrated hemophagocytosis. She was diagnosed with Epstein-Barr-Virus-associated hemophagocytic lymphohystiocytosis and was treated with immunosuppression and chemotherapy. Hemophagocytic lymphohistiocytosis is a rare, life-threatening immune dysregulatory syndrome with both genetic and extragenic triggers that can occur in the postpartum period. Rituximab is an effective add-on therapy to conventional treatment.