RESUMO
BACKGROUND: Hemolytic uremic syndrome is a rare thrombotic microangiopathy characterized by acute renal failure, thrombocytopenia and hemolysis. The underlying abnormality is currently thought to involve enothelial injury within the microcirculation. CASE: A 30-year-old woman, gravida 2, para 1, underwent emergency cesarean delivery at 36 +/- 2 weeks' estimated gestational age for repetitive late decelerations and presumed severe preeclampsia. Postoperatively, the blood pressure remained persistently elevated despite multigent hypertensive therapy. By postpartum day 4 the patient continued to display acute oliguric renal failure, persistent severe thrombocytopenia and worsening hemolysis. Percutaneous renal biopsy was consistent with the clinical diagnosis of hemolytic uremic syndrome. Lupus anticoagulant was present, corroborated by markedly abnormal tissue thromboplastin inhibition and platelet neutralization procedures. With supportive therapy and daily plasmapheresis, the patient was discharged 22 days after delivery, with full recovery of renal function and resolution of the hemolytic process. CONCLUSION: Hemolytic uremic syndrome can be associated with lupus anticoagulant. This autoantibody may promote localized platelet aggregation, causing endothelial damage.
