A Case Report of Atypical Hemolytic Uremic Syndrome in the Setting of Idiopathic Acute Pancreatitis

Hemolytic uremic syndrome (HUS) is a thrombotic microangiopathy defined by the triad of sudden onset hemolytic anemia, thrombocytopenia, and acute kidney injury. We describe a rare case of atypical HUS secondary to acute pancreatitis with an unknown etiology in a 20-year-old male who presented with complaint of nausea, vomiting, and abdominal pain. On presentation, the patient’s vitals were stable and physical exam was significant for epigastric abdominal tenderness. Abdominal imaging showed peripancreatic inflammatory changes consistent with acute pancreatitis and patient had an elevated lipase. Initial investigation reveals acute renal failure, thrombocytopenia and acute pancreatitis. Extensive work-up revealed low C3, and CH50 level, low haptoglobin, and elevated total bilirubin. Due to concern for thrombotic microangiopathy, particularly atypical hemolytic uremic syndrome, the patient was started on plasmapheresis. He remained unresponsive to treatment, thus was followed up with Eculizumab. The patient was also started on Hemodialysis due to worsening renal function and eventually recovered completely. Platelet count improved after initiation of eculizumab and remained stable throughout hospital stay.