SP273ATYPICAL HEMOLYTIC UREMIC SYNDROME SUCCESSFULLY TREATED WITH ECULIZUMAB

Introduction and Aims: Atypical hemolytic uremic syndrome (aHUS) is a rare clinical syndrome characterized by hemolysis, thrombocytopenia, and acute kidney injury. In 90% of patients, HUS is triggered with enteric infections by Shiga toxin-producing bacteria. The remaining cases are referred to aHUS related to dysregulation of the alternative complement system, related to various triggers, such as infection with the human immunodeficiency virus, cancer, organ transplantation, pregnancy, use of certain anticancer drugs, immunotherapeutic agents and antiplatelet. aHUS has a poor prognosis, with death rates as high as 25% and progression to end-stage renal disease in half of the patients. Eculizumab is a monoclonal antibody that targets complement C5 to prevent the activation of the terminal membrane attack complex and thus slow down complement-mediated damage. Methods: A 15y boy was admitted with abdominal pain, edema and hematuria on the previous month. After 1 week, he developed hypertension and oligoanuric AKI, hemolytic anemia, thrombocytopenia and increased LDH. Schizocytes were found in blood smear, with high rates of reticulocytes. low C3 and haptoglobin; direct Coombs, anticardiolipin antibody IgG and IgM, ANA and anti-DNAds sorology for HBV, HCV and HIV were negative. Normal ADAMTS 13 activity and C4. He underwent on daily HD. Treatment with eculizumab started 2 weeks after first session of HD. He increased diuresis and recovered renal function, not requiring HD a month beginning the therapy. He underwent a 1-month induction therapy with eculizumab and maintenance. Renal biopsy was done 3 weeks after admission and showed glomerulies with retraction and epithelial cells with hyperplasia. Endothelial proliferation and obliteration of capillary lumens. Also showed mesangiolisis leading to lumens expansion.