The physician and hereditary angioedema friend or foe : 62-year diagnostic delay and iatrogenic procedures

Background: Hereditary angioedema due to C1 inhibitor deficiency (C1-INH-HAE) is a rare autosomal dominant disease characterized by episodes of acute subcutaneous swelling, and/or recurrent severe abdominal pain. The disease is potentially fatal if the upper-airway is involved. Iatrogenic harm can occur if HAE is not considered in the differential diagnosis, the specialists are not aware of the natural history, diagnosis and treatment of HAE, or as a result of unnecessary surgical and other iatrogenic interventions. Case presentation: We present the case of a 72-year-old man who began suffering recurrent abdominal pain at the age of 8 years. The pain led to frequent emergency department visits, three emergency surgical interventions, and 5 endoscopies before C1-INH-HAE was diagnosed at the age of 70. Infrequent subcutaneous swellings were attributed to unknown allergic reactions that were not related to the primary diagnosis of abdominal pain. Family history was positive for recurrent abdominal pain and angioedema but was ignored until the propositus' grandson developed recurrent severe oro-facial edema attacks. The boy's mother searched the worldwide web and found educational materials on a patient association website. She suggested complement C4 and C1-INH testing that led to the appropriate diagnosis of C1-INH-HAE type 1 in her son and his grandfather. Conclusion: This report emphasizes the importance of accurately evaluating personal and family history in patients with a long history of recurrent, acute, severe but medically unexplained abdominal pain and cutaneous swellings. Here, the diagnosis of HAE was overlooked for 62 years and the focus on abdominal complaints led to numerous surgical interventions without consideration of the full differential diagnosis. Screening family members from all generations for unrecognized angioedema, abdominal pain, and measurement of C1-INH and C4 are essential for accurate and timely diagnosis of HAE