Atypical hemolytic uremic syndrome in a patient with protein-losing enteropathy.

Atypical hemolytic uremic syndrome (aHUS) is an ultra-rare disease induced by many triggers, all of which produce a common end phenotype of microangiopathic hemolysis and thrombotic microangiopathy. We herein describe a 63-year-old woman with ongoing protein-losing enteropathy and frequent transudates caused by hypoalbuminemia. The patient was treated with eculizumab with a full hematologic and partial renal response. Protein-losing enteropathy is an inflammatory condition that has been linked with increased complement activation, which can trigger aHUS in patients with loss of CD55 expression. The patient in the present case had an increased estimated glomerular filtration rate but stage IV to V chronic kidney disease. One year later, she remains off dialysis with a stable estimated glomerular filtration rate. We herein report an unusual trigger of complement activation that in turn triggered aHUS in this patient.