CARDIOVASCULAR JOURNAL OF AFRICA • Vol 21, No 1, January/February 2010
Cardiovascular Topics
32
AFRICA
Cardiac abnormalities and facial anthropometric
measurements in children from the Free State and
Northern Cape provinces of South Africa with
chromosome 22q11.2 microdeletion
SC BROWN, BD HENDERSON, DA BUYS, M THERON, MA LONG, F SMIT
Summary
Introduction:
Microdeletions of chromosome 22 are common
and have a prevalence of at least 1/4 000. Cardiac abnormali-
ties, abnormal facial features and palatal abnormalities are
frequently present in these patients.
Aim:
To describe the cardiac lesions and selected measurable
facial features in children from the Free State and Northern
Cape presenting at the Cardiology Unit of the Universitas
Academic Hospital complex in Bloemfontein.
Methods:
This was a prospective study in which patients with
abnormal facial characteristics were tested using a fluores-
cence
in situ
hybridisation (FISH) probe for the 22q11.2
microdeletion. Forty children tested positive for the micro-
deletion. All patients underwent an echocardiogram and
where possible, facial anthropometric measurements were
performed.
Results:
The median age at diagnosis was 3.6 years (range
0.04 years, i.e. 2 weeks to 16.2 years). Tetralogy with or
without pulmonary atresia was diagnosed in 43% (
n
=
17) of
the children and truncus arteriosus in 20% (
n
=
8). A right-
sided aortic arch was present in 43% (
n
=
17) of the patients.
Mid-facial height was slightly longer (median
z
=
1.0; range
–0.5 to 3.3) and width narrower (median
z
=
–1.4; range –2.2
to 0.1) than normal. Ear height and width were notably small
compared to normal, with median
z
-scores
=
–3.3 (range –4.8
to –2.6) and
z
=
–2.4 (range –3.4 to –1.4), respectively.
Conclusions:
Microdeletions of chromosome 22q11 are
present in children from the Free State and Northern Cape.
Conotruncal cyanotic heart lesions, especially tetralogy with
or without pulmonary atresia and truncus arteriosus were
the most frequent congenital cardiac diagnoses.A right-sided
aortic arch was also commonly present in these children.
Facial features varied and small ears were the most notewor-
thy anthropometric feature.A right-sided aortic arch with or
without a congenital cardiac lesion, a long, narrow mid-face
and small ears should alert the physician to the possibility of
a microdeletion on the long arm of chromosome 22.
Keywords:
cardiac lesion, 22q11 microdeletion, facial anthro-
pometry, echocardiography
Submitted 11/6/09, accepted 25/7/09
Cardiovasc J Afr
2010;
21
: 32–36
Microdeletion of chromosome 22 at the q11 locus is the most
common contiguous gene-deletion syndrome known to man and
may be second only to Down syndrome in order of frequency.
Prevalence estimates vary from one in 2 000 to one in 7 000, but
it is generally accepted to have a prevalence of at least one in
4 000.
1-5
It is clear therefore, that this disorder poses a significant
health concern and clinicians should take note of this condi-
tion. The deleted region is identical in almost 90% of cases and
consists of three million base pairs of DNA, containing a total
of 32 genes.
4
Nomenclature of this disorder has been confusing, most likely
due to the enormous variability in phenotypic expression. It has
been described using various names (e.g. DiGeorge sequence,
Shprintzen syndrome). However, largely due to the dedication
and work of Dr Robert Shprintzen, it is now generally known
as the velocardiofacial syndrome (VCFS). To date, more than
180 phenotypic features have been described, although the major
features of the syndrome are essentially abnormal facial charac-
teristics as well as cardiac and palatal abnormalities.
4,6-8
Detectable cardiac abnormalities may be found in up to 75%
of patients,
9
and are largely responsible for the morbidity and
mortality related to the syndrome.
10
Facial dysmorphology varies
significantly, with ‘classical’ features consisting of a prominent
nasal root, abnormal ears and eyes, and a small mouth (Fig. 1).
No feature is absolutely characteristic and this may lead to under-
recognition of this condition. Furthermore, study populations
predominantly consist of oriental children and those of European
ancestry. In one study,
9
a paucity of the features was recognised
Department of Paediatric Cardiology, Faculty of Health
Sciences, University of the Free State, Bloemfontein, South
Africa
SC BROWN, MMed, FCP (Paed), DCH
DA BUYS, MMed (Paed)
Division of Human Genetics, Faculty of Health Sciences,
University of the Free State, Bloemfontein, South Africa
BD HENDERSON, MMed (Paed)
M THERON, PhD
Department of Cardiothoracic Surgery, Faculty of Health
Sciences, University of the Free State, Bloemfontein, South
Africa
MA LONG, MMed (Surg)
F SMIT, MMed (Surg)
