GUILLAIN-BARRÉ SYNDROME
CHANGES IN BODY PROPORTIONS BETWEEN BIRTH AND ADOLESCENCE
As a child grows, the
body proportions
change radically in
relation to the body’s
overall length (see
right). For example, a
newborn baby’s legs
account for only three
eighths of the body
length, while before
adolescence legs
account for one half.
A newborn’s head
accounts for as much
as a quarter of the
total body length,
while an adolescent’s
head accounts for
only one eighth.
G
o f i t s a d u l t s i z e ; i t g r o w s t o a l m o s t f u l l
s i z e i n t h e f i r s t y e a r . T h e r e a f t e r , i t b e -
c o m e s p r o p o r t i o n a t e l y s m a l l e r b e c a u s e
t h e b o d y g r o w s a t a m
u c h f a s t e r r a t e
t h a n t h a t o f t h e h e a d .
G r o w t h c a n b e i n f l u e n c e d b y
heredity
a n d b y
e n v i r o n m e n t a l f a c t o r s , s u c h a s
n u t r i t i o n a n d g e n e r a l h e a l t h .
Hormones
a l s o p l a y a n i m p o r t a n t r o l e , p a r t i c u l a r l y
growth hormone
, thyroid hormones,
a n d , a t
p u b e r t y , t h e
sex hormones
.
A c h r o n i c i l l n e s s , s u c h a s
cystic fibro-
sis
,
m a y r e t a r d g r o w t h .
E v e n a m i n o r
i l l n e s s c a n s l o w t h e g r o w t h r a t e b r i e f l y ,
a l t h o u g h
t h e
r a t e
u s u a l l y
c a t c h e s
u p
w h e n t h e c h i l d r e c o v e r s . I n s o m e c a s e s ,
s l o w g r o w t h i s t h e o n l y s i g n t h a t a c h i l d
i s i l l , m a l n o u r i s h e d , o r e m o t i o n a l l y d i s -
t r e s s e d , w h e n i t i s k n o w n a s
failure to
thrive
.
H o w e v e r ,
short stature
d o e s
n o t
a l w a y s i n d i c a t e p o o r h e a l t h .
A b n o r m a l l y
r a p i d
g r o w t h
i s
r a r e .
U s u a l l y , i t i s a f a m i l i a l t r a i t , b u t i t m a y
o c c a s i o n a l l y i n d i c a t e a n u n d e r l y i n g d i s -
o r d e r , s u c h a s a p i t u i t a r y g l a n d t u m o u r
c a u s i n g
gigantism
.
( S e e
a l s o
age
;
child
development
.)
growth, excessive
S e e
gigantism
.
growth factor
A n y o f v a r i o u s c h e m i c a l s t h a t a r e i n v o l -
v e d
i n
s t i m u l a t i n g
n e w
c e l l
g r o w t h
a n d m a i n t e n a n c e . S o m e g r o w t h f a c t o r s ,
s u c h a s v a s c u l a r e n d o t h e l i a l g r o w t h f a c -
t o r , w h i c h s t i m u l a t e s t h e f o r m a t i o n o f
n e w b l o o d v e s s e l s , a r e s i g n i f i c a n t i n t h e
g r o w t h a n d s p r e a d o f c a n c e r s .
growth hormone
A s u b s t a n c e
p r o d u c e d b y
t h e
pituitary
gland
t h a t
s t i m u l a t e s
n o r m a l
b o d y
g r o w t h . G r o w t h h o r m o n e i n c r e a s e s t h e
p r o d u c t i o n
o f p r o t e i n i n
m u s c l e
c e l l s
a n d
t h e
r e l e a s e
o f
e n e r g y
f r o m
t h e
b r e a k d o w n o f f a t s . O v e r s e c r e t i o n o f t h e
h o r m o n e l e a d s t o
gigantism
i f i t o c c u r s
b e f o r e p u b e r t y o r
acromegaly
i f i t o c c u r s
a f t e r w a r d s . A d e f i c i e n c y o f t h e h o r m o n e
m a y
r e s u l t
i n
short stature
.
S y n t h e t i c
g r o w t h
h o r m o n e
m a y
b e
g i v e n
b y
i n j e c t i o n t o t r e a t s h o r t s t a t u r e c a u s e d b y
p i t u i t a r y o r g e n e t i c d i s o r d e r s .
growth rate
T h e
i n c r e a s e
i n
s i z e
o f a n
i n d i v i d u a l
o v e r
a
g i v e n
p e r i o d
o f t i m e .
G r o w t h
r a t e m a y b e e x p r e s s e d i n a b s o l u t e t e r m s
o r r e l a t i v e l y , a s a p e r c e n t a g e o f t h e a v e r -
a g e
g r o w t h
r a t e .
( S e e
a l s o
growth,
childhood
; height velocity.)
growth, restricted
S e e
short stature
.
G syndrome
S e e
Opitzsyndrome
.
GTN
T h e a b b r e v i a t i o n f o r
glyceryl trinitrate
.
guaiac
A c h e m i c a l u s e d t o d e t e c t h a e m o g l o b i n
( t h e
o x y g e n - c a r r y i n g
p i g m e n t
i n
r e d
b l o o d c e l l s ) i n f a e c e s . T e s t s u s i n g g u a i a c ,
k n o w n a s
faecal occult blood tests
,
a r e p e r -
f o r m e d t o d e t e c t h i d d e n b l e e d i n g i n t h e
d i g e s t i v e t r a c t ( s e e
occult blood, faecal
).
guar gum
A g u m e x t r a c t e d f r o m t h e c l u s t e r b e a n
( C y a m o p s is
t e t r a g o n o l a b a ) .
G u a r g u m
i s
n o t d i g e s t e d i n t h e b o d y I t i s u s e d t o
h e l p c o n t r o l t h e b l o o d
glucose
l e v e l i n
p e o p l e w i t h
diabetes mellitus
b e c a u s e i t
s l o w s t h e
a b s o r p t i o n
o f g l u c o s e
f r o m
t h e s m a l l i n t e s t i n e . T h e g u m i s t a k e n a s
g r a n u l e s s p r i n k l e d o n f o o d o r d i s s o l v e d
i n w a t e r . I t m a y c a u s e
flatulence
,
n a u s e a ,
a n d a b d o m i n a l d i s c o m f o r t .
Guillain-Barre syndrome
A r a r e c o n d i t i o n a f f e c t i n g t h e
peripheral
nervous system
t h a t
c a u s e s
w e a k n e s s ,
u s u a l l y i n t h e l i m b s .
CAUSES
T h e c a u s e o f G u i l l a i n - B a r r e s y n d r o m e
i s b e l i e v e d t o b e a n a l l e r g i c r e a c t i o n t o
a n
i n f e c t i o n ,
u s u a l l y
v i r a l ;
t h e
n e r v e s
a r e
d a m a g e d
b y
antibodies
p r o d u c e d
a g a i n s t
t h e
v i r u s .
M o s t
c a s e s
d e v e l o p
t w o o r t h r e e w e e k s a f t e r t h e i n f e c t i o n .
SYMPTOMS
W e a k n e s s ,
o f t e n
a c c o m p a n i e d
b y
n u m b n e s s a n d t i n g l i n g , u s u a l l y s t a r t s i n
t h e l e g s a n d s p r e a d s t o t h e a r m s . I t m a y
w o r s e n , r e s u l t i n g i n
paralysis
.
T h e m u s -
c l e s
o f t h e f a c e
a n d t h o s e
c o n t r o l l i n g
s p e e c h , s w a l l o w i n g , a n d b r e a t h i n g m a y
a l s o b e a f f e c t e d .
DIAGNOSIS AND TREATMENT
D i a g n o s i s i s c o n f i r m e d b y e l e c t r i c a l t e s t s
t o m e a s u r e h o w f a s t n e r v e i m p u l s e s a r e
c o n d u c t e d , a n d b y a
lumbar puncture
,
i n
w h i c h a s a m p l e o f c e r e b r o s p i n a l f l u i d i s
t a k e n f r o m t h e s p i n a l c a n a l f o r a n a l y s i s .
M o s t p e o p l e r e c o v e r f u l l y w i t h o n l y
s u p p o r t i v e t r e a t m e n t . S e v e r e c a s e s m a y
351
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