Feeding, weight gain, and faulure-to

1
Feeding, weight gain,
and faulure-to-thrive
VCFS is caused by a deletion of 22q11.2
One of our 2 copies of chromosome 22 loses 40 genes
Genes (40)
Pseudogenes (8)
R
SERPIND1
SNAP29
CRKL
VCF-E
LZTR
VCF-F
VCF-G
P2RXL1
SLC7A4
R
USP18-p
ZNF74
SRECII
VCF-D
PCQAP
R
DGCR6
PRODH2
DGCR5
CALS2
IDD
TSK-P
TSK-1
DGS-I
GSCL
CTP
CTLD
HIRA
NLVCF
VCF-A
UFD1L
CDC45L
TMVCF
PNUTL
GP1B
TBX-1
WDR14
TRXR2
COMT
ARVCF
T10
DGCR8
HTF9C
RANBP1
KIAA1292
VCF-B
VCF-C
NOGOR
PRODH2-p
DGCR6-L
Genome at 22q11.2
R
R Low copy repeats (4)
Most individuals with VCFS are missing 40 genes on
one copy of chromosome 22. One or more of these
genes may contribute to normal growth or normal
growth velocity as regulated by hormones or some
other timing mechanism
Many (most) children with VCFS
have low weight and short stature
when compared to the CDC
growth charts that are normed for
the general population. This is
especially true for infants, toddlers
and young children.
Is it appropriate to compare children
with VCFS (people missing 40 genes)
to growth velocity curves that are
normed for people who do not have
VCFS (who are not missing 40 genes)?
Research has already demonstrated
that muscle mass in people with VCFS
is reduced for at least some parts of
the body. There are fewer muscle
fibers and the each muscle fiber is
smaller than normal.
Muscle is a dense and heavy tissue
that accounts for a high percentage
of body weight.
Weight proportion is different in
VCFS than in the general population
subcutaneous fat
True failure-to-thrive
subcutaneous fat
VCFS baby with failure-tothrive based on CDC data
There are growth curves specific to
other syndromes such as Down
syndrome and Williams syndrome.
Down syndrome
Williams syndrome
Growth Data for VCFS
Method
Retrospective
data from 1,085 patients with
VCFS who had multiple documented heights and
weights
All data pooled according to age and sex
Presence or absence of heart anomalies assessed
as variables
Presence or absence of feeding difficulties, Gtubes, etc., were assessed as variables
VCFS Growth Chart, males, length and weight, 0 - 36 months of age
VCFS Growth Chart,
Length and Weight,
boys 0 - 36 months of
age compared to CDC
norms used for the
general population
VCFS Growth Chart, males, 2-20 years
VCFS Growth Chart,
Height and Weight,
males 2 - 20 years of
age compared to CDC
norms used for the
general population
VCFS Growth Chart, females, length and weight, 0 - 36 months of age
VCFS Growth Chart,
Height and Weight,
females 0 - 36 months
of age compared to
CDC norms used for
the general population
VCFS Growth Chart, females, 2-20 years
VCFS Growth Chart,
Height and Weight,
females 2 - 20 years of
age compared to CDC
norms used for the
general population
Comparisons
 The
presence of heart anomalies was not a factor in longterm growth except in early infancy and in severe cases
with pulmonic stenosis/atresia
 Males reached averaged parental heights, females tended
to fall slightly short
 In childhood, weight was low compared to height
(typically between the 10th to 25th centile) according to
CDC norms
 Following puberty, weight was proportionate to height
 Growth velocity in VCFS differs from the general
population
Comparisons
Head
circumference growth was independent of
somatic growth and weight
Early feeding difficulties were not predictive of
short stature or low weight as an adolescent or
adult
The presence of alternative feeding in infancy
did not increase linear growth velocity
In other words, the effects of the deletion was the
major influence on growth
The overwhelming majority of people with
chromosomal rearrangements involving multiple
genes have abnormal growth patterns, and the
large majority of them have growth velocities that
do not look like the general population.
Comparing people with genetic or chromosomal
rearrangements to growth charts based on the
general population in order to recommend
treatment is not appropriate.
Therefore, treating children with VCFS
in a manner that is designed to have
them fit the norms for the general
population is inappropriate.