Successful use of daily intravenous infusion of C1 esterase inhibitor concentrate in the treatment of a hereditary angioedema patient with ascites, hypovolemic shock, sepsis, renal and respiratory failure

Hereditary angioedema (HAE) is a rare autosomal dominant disease most commonly associated with defects in C1 esterase inhibitor (C1-INH). HAE manifests as recurrent episodes of edema in various body locations. Atypical symptoms, such as ascites, acute respiratory distress syndrome, and hypovolemic shock, have also been reported. Management of HAE conventionally involves the treatment of acute attacks, as well as short- and long-term prophylaxis. Since attacks can be triggered by several factors, including stress and physical trauma, prophylactic therapy is recommended for patients undergoing surgery. Human plasma-derived C1-INH (pdC1-INH) concentrate is indicated for the treatment of both acute HAE attacks and pre-procedure prevention of HAE episodes in patients undergoing medical, dental, or surgical procedures. We report the first case of a patient with HAE who experienced an abdominal attack precipitated by a retroperitoneal bleed while being converted from warfarin to heparin in preparation for surgery. Subsequently, the patient had a protracted course in hospital with other complications, which included hypovolemic shock, ascites, severe sepsis from nosocomial pneumonia, renal and respiratory failure. Despite intensive interventions, the patient remained in a critical state for months; however, after a trial of daily intravenous infusion of pdC1-INH concentrate (Berinert®, CSL Behring GmbH, Marburg, Germany), clinical status improved, particularly renal function. Therefore, pdC1-INH concentrate may be an effective treatment option to consider for critically-ill patients with HAE.