Time course of organ dysfunction in thrombotic microangiopathy patients receiving either plasma perfusion or plasma exchange

Introduction: Few studies have investigated adults with thrombotic microangiopathy (TMA) requiring intensive care unit (ICU) admission, and the treatment remains controversial. Objective. To describe causes, outcomes, prognostic factors, and daily organ-failure score changes in adults with TMA requiring ICU admission. Design. A 3-yr single-center cohort study. Patients. The patients were 36 adults with TMA admitted to a teaching-hospital medical ICU between January 2000 and June 2003. Results: Of the 36 patients, 22 received plasma infusion and 15 underwent plasma exchange. All patients had anemia and thrombocytopenia at ICU admission, and 13 had neurologic impairment. Median creatinine clearance was 55.2 mL/min (interquartile range, 28.8-75.4). No patient had congenital TMA. Causative factors included microbiologically documented infection in 14 patients, allogeneic transplantation in 7 patients, and concomitant or subsequent systemic disease in 7 patients; 6 patients were human immunodeficiency virus-positive, 5 had drug-induced TMA, 2 were pregnant, and 2 had cancer. In 10 patients, no causative factors were identified. Plasma exchange was associated with a statistically significant decrease in hospital mortality (0 vs. 7 deaths; p <.001). Moreover, daily organ-failure scores were significantly lower in the plasma-exchange group from day 3 to day 9. Patients in the plasma-exchange group received a larger volume of plasma. Conclusion: Plasma exchange may be associated with faster resolution of organ failure and with improved survival for patients with TMA requiring ICU admission.