RESUMO
Hereditary angioedema (HAE) is a rare genetic disorder characterized by potentially life-threatening episodes of swelling. Most HAE cases are caused by deficient (type I) or dysfunctional (type II) C1-esterase inhibitor (C1-INH) protein. However, some patients present with a subtype of HAE that is associated with normal plasma levels of functional C1-INH protein and complement component 4 (HAE-nC1INH). Treatment of HAE-nC1INH is driven by clinical experience as robust clinical trial data to inform treatment decisions are lacking in this population. This retrospective case series assessed clinical features and treatment outcomes in 15 patients with HAE-nC1INH who initiated long-term prophylaxis with oral berotralstat 150 mg once daily as part of their disease management pathway. Most patients were female (93%), with a median age of 49 years. All patients experienced abdominal swelling attacks. On average, patients tried a mean of 4 different treatments for their HAE, including berotralstat. Although most patients associated prophylactic and on-demand medications that target the bradykinin pathway with improvements in the frequency and/or severity of attacks, treatment outcomes varied considerably between patients, highlighting the importance of a personalized approach to disease management. In this case series, berotralstat was an effective prophylactic treatment option in most patients with HAE-nC1INH. Further studies are required to demonstrate the potential efficacy, safety, and impact on quality of life of currently approved HAE therapies in patients with HAE-nC1INH.
RESUMO
Genetic testing is a state-of-the-art and readily accessible diagnostic tool and is increasingly indicated in the evaluation process when relevant and possible, although incorporation of this modality into the daily practice of allergists-immunologists in both academic and nonacademic or community settings is still a challenge. Educational sessions and resources support the use of genetic testing in the diagnosis and management of primary immunodeficiency by both the American Academy of Allergy, Asthma & Immunology and the Clinical Immunology Society. Genetic testing for primary immunodeficiency has become much more convenient and affordable over the past decade; allergist-immunologists in private practice are now able to offer patients high-quality and comprehensive genetic testing panels to help diagnose or characterize underlying immune abnormalities among patients with recurrent infections, and even patients with allergic disorder and noninfectious complications. Although genetic testing has not been a commonplace consideration in day-to-day practice for many nonacademic specialists, a shift toward adopting this into our standard toolkit should be taking place. Most of the commercial genetic testing is aiming for a panel of genes ranging anywhere from just a few to several hundred, so the specialist can feel comfortable clearly interpreting the data. As the panels are analyzing data from next-generation sequencing and deletion/duplication assays, this evaluation may need to be repeated when panels expand and include new relevant genes. Ultimately, for undiagnosed cases, whole-exome and whole-genome sequencing can be the next step; however, involvement of genetic counselors may be needed to interpret the data. The value of genetic testing is that it may bring the clinician closer to an accurate diagnosis; therefore, we can keep treating our patients more accurately and effectively, which may result in less frequent follow-ups for unresolved or recurrent problems. In addition, we can then provide patients and their families with important information about the root cause of their disease state, risks to other family members, and offer genetic counseling services. Genetic testing results may also aid in recognizing when a referral to expert colleagues for more advanced and specialized treatments is indicated.