A 3-year-old boy presented to the pediatrics ER with significant dehydration along with irritability, weakness and severe lethargy. His mother says he suffered from bloody diarrhea along with fever and abdominal pain 8 days ago. Lab findings, Anemia Deranged RFTs Thrombocytopenia Severe hyponatremia Leukocytosis. PT and aPTT -normal Coombs test- negative. Urine analysis revealed microscopic haematuria and low-grade proteinuria. Peripheral blood smear If there would not have been any history of diarrhea in the above patient, which of the following drugs could have been given in the above patient: -

This is a case of typical HUS. If history of diarrhoea would had been absent, the diagnosis would had been atypical HU for which FDA has approved eculizumab. Peripheral blood smear shows the presence of burr cells and schistocytes - suggestive of microangiopathic hemolytic anemia. Eculizumab Anti-C5 antibody Inhibits complement activation Approved for the treatment of: - Paroxysmal nocturnal hemoglobinuria (PNH) to reduce hemolysis Atypical hemolytic uremic syndrome to inhibit complement-mediated thrombotic microangiopathy Caplacizumab is a bivalent Single-domain antibody (VHH) designed for the treatment of thrombotic thrombocytopenic purpura and thrombosis Omalizumab and Mepolizumab are given in asthma patients. Hemolytic uremic syndrome Syndrome characterized by: - Progressive renal failure Microangiopathic (nonimmune, coombs-negative) hemolytic anemia Thrombocytopenia Damage to endothelial cells is the primary event in the pathogenesis of hemolytic-uremic syndrome (HUS). Two monoclonal antibodies, eculizumab and ravulizumab, are approved for the treatment of pediatric and adult patients with atypical HUS.