LEUKODYSTROPHIES
LEUKAEMIA
In all forms of leukaemia, abnormal
white cells proliferate in the bone
marrow and spill into the blood.
There are four main types: acute
lymphoblastic leukaemia (ALL), acute
myeloblastic leukaemia (AML), chronic
lymphocytic leukaemia (CLL), and
chronic myeloid leukaemia (CML). The
acute types have a rapid onset. There
Symptoms of
acute leukaemia
Symptoms are caused partly
by the abnormal white cells
crowding outthe bone marrow
(so that it fails to produce
sufficient normal blood cells
of all types) and partly by the
invasion of other body organs
by abnormal cells.
G u m b l e e d i n g
G u m s m a y b l e e d a s a r e s u l t
o f i n s u f f i c i e n t p r o d u c t i o n
o f p l a t e l e t c e l l s b y t h e b o n e
m a r r o w ; p l a t e l e t s a r e n e e d e d
f o r t h e a r r e s t o f b l e e d i n g .
is a risk of death from overwhelming
infection or blood loss, but modern
treatment has greatly improved
survival rates, particularly in
childhood leukaemias.
The chronic forms of leukaemia
progress much more gradually than
the acute types, but many of them
are essentially incurable.
B o n e t e n d e r n e s s
T e n d e r n e s s o f t h e b o n e s m a y
b e f e l t a s t h e b o n e m a r r o w
b e c o m e s p a c k e d w it h
i m m a t u r e w h it e c e l l s .
E a s y b r u i s i n g a n d b l e e d i n g
R e d u c e d n u m b e r s o f p l a t e l e t s
m a y l e a d t o b l e e d i n g f r o m
n o s e a n d g u m s a n d b r u is in g
a f t e r m i l d t r a u m a .
------
H e a d a c h e
H e a d a c h e m a y b e c a u s e d
b y a b n o r m a l w h it e c e l l s
a f f e c t i n g t h e n e r v o u s
s y s t e m .
E n l a r g e d ly m p h n o d e s
T h e l y m p h n o d e s in t h e
n e c k , a r m p i t s , a n d g r o i n
m a y b e s w o l l e n w it h h u g e
n u m b e r s o f i m m a t u r e w h it e
c e l l s . T h e liv e r , s p l e e n , a n d
t e s t e s m a y a l s o b e s w o l le n .
A n a e m i a
A n a e m i a d e v e l o p s i f t h e r e
is i n s u f f i c i e n t p r o d u c t i o n o f
r e d b l o o d c e l l s b y t h e b o n e
m a r r o w . A n a e m i a c a u s e s
t ir e d n e s s , b r e a t h l e s s n e s s
o n e x e r t io n , a n d p a llo r .
I n f e c t i o n s
W h ite b l o o d c e l l s p l a y a
m a j o r p a r t i n t h e d e f e n c e
a g a i n s t i n f e c t i o n . H o w e v e r ,
in a c u t e l e u k a e m i a , o n l y
i m m a t u r e , n o n f u n c t io n in g
w h it e c e l l s a r e m a d e , s o t h e
p a t i e n t m a y s u f f e r f r o m
r e p e a t e d c h e s t o r t h r o a t
i n f e c t i o n s , h e r p e s z o s t e r ,
o r s k i n a n d o t h e r in f e c t i o n s .
HOW LEUKAEMIA
ATTACKS THE BODY
Leukaemia is a form of cancer, but
with the abnormally growing cells
(mutated white blood cells) forming
in the bone marrow rather than
grouped into a tumour in a specific
area. The abnormal cells may spill
into the bloodstream and infiltrate
and interfere with the function of
other organs. But worse, these cells
“take over” the marrow and prevent
it from making enough normal blood
cells (including normal white cells,
red cells, and platelets). This leaves
the sufferer highly susceptible to
serious infections, anaemia, and
bleeding episodes.
W h ite c e l l s f i g h t
in f e c t i o n
P l a t e l e t s h e l p
b l o o d t o c l o t
R e d c e l l s
t r a n s p o r t o x y g e n
Normal appearance of blood
In a normal blood smear, there are large
numbers of red cells, many platelets, and
a few white cells.
A b n o r m a l w h it e
c e l l s ( s u s c e p t i b i l i t y
t o i n f e c t i o n )
F e w e r p l a t e l e t s
( b l e e d i n g t e n d e n c y )
F e w e r r e d c e l l s
( a n a e m i a )
Appearance of blood in leukaemia
In leukaemia, the blood usuallycontains
many abnormal white cells, and fewer red
cells and platelets.
L
SYMPTOMS
D u r i n g t h e c h r o n i c p h a s e , s y m p t o m s a r e
n o t a l w a y s o b v i o u s ,
a l t h o u g h t h e y m a y
i n c l u d e f e v e r ,
n i g h t s w e a t s ,
a n d w e i g h t
l o s s .
H i g h n u m b e r s
o f w h i t e c e l l s m a y
c a u s e t h e b l o o d t o b e c o m e v e r y t h i c k a n d
u n a b l e t o f l o w t h r o u g h t h e s m a l l e s t v e s -
s e l s , l e a v i n g t i s s u e s s t a r v e d o f o x y g e n . T h e
r e s u l t s
i n c l u d e
v i s u a l
d i s t u r b a n c e s ,
a s
b l o o d v e s s e l s i n t h e e y e a r e a f f e c t e d , a n d
a b d o m i n a l p a i n d u e t o t h e d e a t h o f t i s s u e s
i n t h e s p l e e n ;
p r i a p i s m
( p e r s i s t e n t , p a i n f u l
e r e c t i o n o f t h e p e n i s ) m a y a l s o o c c u r .
T h e s y m p t o m s o f t h e a c c e l e r a t e d p h a s e
a r e l i k e t h o s e o f a c u t e l e u k a e m i a
( s e e
l e u k a e m i a
,
a c u t e )
.
DIAGNOSIS AND TREATMENT
T h e d i a g n o s i s i s m a d e f r o m b l o o d t e s t s
a n d a
b o n e m a r r o w b i o p s y
.
T r e a t m e n t o f
t h e
c h r o n i c
p h a s e
i n c l u d e s
a n t i c a n c e r
d r u g s
o r a l p h a
i n t e r f e r o n s
.
A
b o n e m a r r o w
t r a n s p l a n t
i s a l s o p o s s i b l e i f a s u i t a b l e
d o n o r c a n b e f o u n d . W
h e n t h e d i s e a s e
t r a n s f o r m s
i n t o
t h e
a c u t e
p h a s e ,
t h e
t r e a t m e n t i s
s i m i l a r t o
t h a t
g i v e n
f o r
a c u t e l e u k a e m i a .
le u k o c y te
A n y t y p e o f w h i t e
b l o o d c e l l
.
le u k o d y s tro p h ie s
A
r a r e
g r o u p
o f i n h e r i t e d
c h i l d h o o d
d i s e a s e s i n w h i c h t h e
m y e l i n
s h e a t h s t h a t
f o r m
a
p r o t e c t i v e
c o v e r i n g
a r o u n d
m a n y
n e r v e s , p a r t i c u l a r l y i n t h e b r a i n
a n d t h e s p i n a l c o r d , a r e d e s t r o y e d . T h e
l e u k o d y s t r o p h i e s
c a u s e
s e v e r e l y
d i s -
a b l i n g
c o n d i t i o n s ,
s u c h
a s
i m p a i r e d
s p e e c h ,
b l i n d n e s s
,
d e a f n e s s
,
a n d
p a r a -
l y s i s
,
a n d a r e a l w a y s f a t a l .
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