Abstract Background Angioedemas localized in the upper airway are potentially life
threatening, and without proper treatment, they may lead to death by suffocation.
Upper airway edemas (UAE) in bradykinin-mediated angioedemas can even be the first
symptoms of the disease. Methods Our survey was performed with a retrospective long-term
follow-up method from the medical history of 197 hereditary (C1-INH-HAE) and 20 acquired
C1-inhibitor deficiency (C1-INH-AAE), 3 factor XII and 3 plasminogen gene mutation
(FXII-HAE, PLG-HAE) patients treated at our center between 1990 and 2020. The UAE
group included edemas localized to the mesopharynx, hypopharynx, and larynx, as narrowing
of these anatomical regions can lead to suffocation. Results 98/197 C1-INH-HAE (47
families) and 13/20 C1-INH-AAE, 1/3 PLG-HAE, 1/3 FXII-HAE patients had experienced
UAE at least once according to their medical history. In case of C1-INH-HAE patients,
in 6/47 families who had undiagnosed ancestors had 13 members who died of suffocation.
After the diagnosis, 1-1 member of two families died of UAE. 44/64 C1-INH-HAE patients
did not smoke, 20/64 did. The occurrence of UAE was significantly higher in smoker
patients. We analyzed 7607 HAE attacks of 56/98 patients. Out of all attacks, the
incidence of UAE in the C1-INH-HAE group was 4%, and 9.5% in the C1-INH-AAE group,
respectively. Conclusion Early diagnosis is key in bradykinin-mediated angioedemas
cases, since the patient must be provided with adequate treatment; and also it is
essential to inform patients about the importance of avoiding the trigger factors
and the early symptoms of UAE, as these measures could significantly decrease the
incidence of lethal UAEs.
