Training Hereditary Angioedema Patients to Self-administer Intravenous C1 Esterase Inhibitor Concentrate

Abstract

Hereditary angioedema (HAE) is a rare disorder that causes periodic attacks of sometimes painful swelling that may affect any organ system. HAE results in significant morbidity and diminished quality of life and requires patients to seek urgent medical care. HAE can be treated with C1 esterase inhibitor concentrate (C1-INH), icatibant, and ecallantide. Recent consensus guidelines recommend that all HAE patients be considered for training in self-administration of therapy to treat acute attacks or to prevent attacks. Many patients have safely and successfully self-administered intravenous infusions of C1-INH, resulting in rapid treatment, shortened attacks, and improved quality of life. With proper patient selection and adequate guidance and follow-up, self-administered C1-INH therapy is a viable and favorable option to treat HAE, particularly in patients with a moderate to high frequency of attacks.

Hereditary Angioedema: An Emergency Nursing Perspective

“…3 Type II HAE is characterized by a mutation that results in a dysfunctional C1 inhibitor protein and low level of C4. [1][2][3]14 Type III HAE is sometimes also called "HAE with normal C1 inhibitor" and is more common in women. 1,3 With type III, the C1 inhibitor has normal levels and functionality.…”

“…Approximately 25% of patients with type III HAE have a mutation for the factor XII gene, which promotes kinin production. 3,9,14 Signs and Symptoms Patients with HAE have episodes of non-pitting, nonpruritic swelling of the extremities, abdomen, face, or upper airway. 1 In a typical episode, the swelling severity gradually increases over the first 24 hours and then gradually decreases over the next 48 to 72 hours.…”

“…Type I HAE is caused by a mutation that results in truncated or misfolded C1 inhibitor proteins. 14 Type I is characterized by low levels of C1 inhibitor and low levels of C4. [1][2][3] Overall, approximately 85% of individuals with HAE have type I.…”

“…Even if episodes are controlled with self-administration, each episode, no matter the severity, should be reported to track frequency and treatment efficacy. 7,14 Methods for managing HAE generally focus on the restoration of the C1 inhibitor deficiency and the prevention of bradykinin accumulation. 2,25 There are 2 preventative approaches: short-term and long-term prophylaxis.…”

Prophylaxis in hereditary angioedema (HAE) with C1 inhibitor deficiency

“…Results from clinical trials show that self‐administration leads to better and more effective treatment, fewer days of sick leave, and an increase in the quality of life . In general, most patients readily learn and successfully employ the injection technique after thorough instruction .…”