18
In a study in 221 patients in Germany, Bork et al reported a
mean age at symptom onset of 11.2 years, with a standard
deviation (SD) of 7.7 years (Figure 7).
31
Even earlier onset of HAE symptoms at a mean age of
6.6 years in 49 pediatric patients with HAE was reported
from the Hungarian HAE Center.
32
In an international
registry funded by the European Commission (PREHAEAT),
the median age at onset of HAE symptoms was 11 years
(range 0 to 38 years) for 1,168 patients from 10 countries.
23
However, the median age at diagnosis was 26 years (range
0 to 90 years).
23,33
Similar observations were made in a
nationwide survey performed in Denmark for 82 patients
with HAE; the mean age at symptom onset was 9.5 years
with a diagnostic delay of 16.3 years.
21
Delay in diagnosis is not uncommon, because of HAE’s
resemblance to more common conditions and low aware-
ness of HAE among healthcare professionals.
5
3.13 Varied Location and Duration of Attacks
Acute episodes of angioedema in HAE can be localized
anywhere in the body, including the trunk (Figure 8).
Age at Onset of Clinical Symptoms
15
10
5
0
Number of Patients
Age at Onset (years)
0
10
30
20
40
Figure 7 – Age at Onset of Clinical Symptoms
in 221 Patients With Hereditary Angioedema
Figure 8 – Common Sites of Attacks
in Hereditary Angioedema
Face
– If left untreated, some disfiguring
facial attacks can progress to the tongue,
larynx, and glottis, compromising the
airway
Larynx, Glottis, or Tongue
– Laryngeal,
glottal, and lingual attacks can lead to
asphyxiation
Gastrointestinal Tract
– Frequent site
of painful attacks, often with dizziness,
nausea, vomiting, diarrhea; rarely,
hypotensive shock ensues
Genitourinary System
– Less typical
Hand and Arm
– Cutaneous attacks
of extremities are common and can
affect dexterity
Leg and Foot
– Cutaneous attacks of
extremities can impede function
Face
– If left untreated, some disfi uring
f ci l attacks can progress to the tongue,
lary x, and glottis, c promising the
irway
Larynx, Glottis, or Tongue
– Laryngeal,
g ottal, a d lingu l attacks c n lead to
asphyxiation
Gastrointestin l Tract
– Frequent site
of painful attacks, often w th dizziness,
n usea, vomiting, di rrhea; rarely,
hypot nsive shock nsues
Genitourinary System
– Less typical
H and Arm
– Cutaneous attacks
of ex r miti s are c mmon and can
aff c dexterity
Leg and Foot
– Cutaneous attacks of
ex r mities can impede fu ction
The mechanism of action and roles of C1-INH
are discussed in greater depth in chapter 7 of
this monograph.
