Spectra Optia granulocyte apheresis collections result in higher collection efficiency of viable, functional neutrophils in a randomized, crossover, multicenter trial.

BACKGROUND: Granulocyte transfusion from healthy donors is used in the treatment of patients with granulocyte function defects, or transient neutropenia and severe bacterial or fungal infections resistant to maximal antimicrobial treatment. STUDY DESIGN AND METHODS: This study evaluated the performance and safety of the newly developed granulocyte collection protocol of the Spectra Optia in a prospective, multicenter, open-label, randomized, paired crossover trial compared with the COBE Spectra apheresis system in a population of 32 evaluable healthy subjects. All subjects received granulocyte-colony-stimulating factor and dexamethasone before collection. RESULTS: Granulocyte procedures from Spectra Optia apheresis procedures had an approximately 23% higher polymorphonuclear (PMN) collection efficiency (CE) than the COBE Spectra collections (mean, 53.7% vs. 43.2%; p < 0.01), while the platelet CE (10.9% vs. 10.8%, respectively) and hematocrit (7.4% vs. 7.4%) were comparable between collections on both devices. Spectra Optia collections generated a higher total PMN yield per liter of blood processed than those produced by the COBE Spectra (with means of 8.6 × 10(10) vs. 6.8 × 10(10) , respectively). Granulocyte viability was more than 99% with both devices, and chemotaxic and bacterial killing activities of circulating versus collected granulocytes were similarly preserved. Fewer operator adjustments were required with Spectra Optia and there was no significant difference in the number or intensity of adverse events between instruments. CONCLUSION: CE of the granulocyte collection procedure with the Spectra Optia was approximately 10 percentage points higher than with the COBE Spectra, required less operator involvement, and is safe for clinical implementation.

Does early initiation of therapeutic plasma exchange improve outcome in pediatric stem cell transplant-associated thrombotic microangiopathy?

BACKGROUND: The use of therapeutic plasma exchange (TPE) in hematopoietic stem cell transplant-associated thrombotic microangiopathy (TA-TMA) is controversial because the exact mechanism of injury in TA-TMA is not yet understood. STUDY DESIGN AND METHODS: The study objective was to retrospectively review the outcome of children receiving TPE for TA-TMA at our institution. We hypothesized that patients initiating TPE earlier in their disease course would receive a greater benefit than those starting later, regardless of the therapeutic mechanism. RESULTS: We identified 10 consecutive pediatric patients with TA-TMA treated with TPE. Nine of these patients showed normalization of the laboratory variables associated with microangiopathy during their TPE course, but only five patients recovered renal function and survived TA-TMA. The five survivors started TPE a median of 17 days (range, 4-25 days) after TA-TMA diagnosis while the five patients who died started TPE a median of 32 days (range, 17-73 days) after TA-TMA was diagnosed. Three of the five survivors had multiorgan failure at TA-TMA diagnosis and completely recovered with early institution of TPE. These three survivors were able to discontinue renal replacement therapy, and all achieved a normal posttreatment creatinine. The five patients with later institution of TPE progressed to end-stage renal disease and all died. There were no serious TPE-related complications in either group. CONCLUSION: This is the first report evaluating TPE response in regard to procedure initiation time after TA-TMA diagnosis. Our data suggests that early initiation of TPE might be beneficial even in patients with multiorgan failure due to TA-TMA.

Successful early intervention for hyperacute transplant-associated thrombotic microangiopathy following pediatric hematopoietic stem cell transplantation.

TA-TMA is a serious complication of hematopoietic stem cell transplantation, presenting as microangiopathic hemolytic anemia with severe renal injury and mortality as high as 60%. Diagnosis and treatment of TA-TMA is very challenging after HSCT because anemia, thrombocytopenia, hypertension, and renal impairment are multifactorial, leading to delayed recognition and management of this complication. We report a successful outcome following early intervention for hyperacute TA-TMA after allogeneic HSCT.