LIVER, CIRRHOSIS OF
L
DISORDERSOFTHE LIVER
The most common cause of liver disease
in developed countries is excessive
alcohol consumption. Alcohol-related
disorders (see
l i v e r d i s e a s e , a l c o h o l i c )
include
h e p a t i t i s
(liver inflammation)
and
c i r r h o s i s .
Many other types of liver
disorder may occur, including infections,
tumours, metabolic disorders, and
congenital defects.
L i v e r f a i l u r e
(complete loss of liver
function) may occur as a result of acute
hepatitis, poisoning, or cirrhosis.
J a u n d i c e
and hepatomegaly (enlargement of the
liver) are common signs of liver disease.
Infection and inflammation
Hepatitis is a general term for
inflammation of the liver. It can be
caused by viruses (see
h e p a t i t i s , v i r a l
)
or bacteria, which may spread up the
biliary system to the liver, causing
c h o l a n g i t i s
(inflammation of the bile
duct) or
l i v e r a b s c e s s
. Parasitic diseases,
including
s c h i s t o s o m i a s i s , l i v e r f l u k e ,
a m o e b i a s i s ,
and
h y d a t i d d i s e a s e ,
can
also affect the liver.
Tumours
The liver is a common site for
cancerous tumours that have spread
from elsewhere in the body (in which
case they are known as secondary
tumours of the liver). Primary tumours
of the liver (those that originate in the
liver) are much rarer. (See
l i v e r c a n c e r . )
Metabolic disorders
Two main
m e t a b o l i c d i s o r d e r s
affect the
liver:
h a e m o c h r o m a t o s i s
(in which there
is too much iron in the body) and
W i l s o n ' s d i s e a s e
(in which there is an
excess of copper in the liver).
Congenitaldefects
Occasionally, defects of liver structure
are present from birth. Abnormalities
such as these principally affect the
bile ducts. A choledochal cyst is a
malformation of a main bile duct.
These cysts require surgery because,
in infants, they may obstruct the flow
of bile, causing jaundice.
B i l i a r y a t r e s i a ,
in which the bile ducts are missing,
also causes jaundice.
Poisoning and drugs
Normally, the liver can break down
drugs and toxins. However, drug
overdose or allergy may damage liver
cells in the process, and overdose of
paracetamol can lead to severe liver
damage. Poisoning by certain types of
mushroom can cause acute liver failure.
Other disorders
In
B u d d - C h i a r i s y n d r o m e ,
the veins
draining the liver become blocked
by blood clots, which causes painful
swelling of the liver. Obstruction of
the portal vein is one cause of
p o r t a l
h y p e r t e n s i o n
(high blood pressure in
the portal vein), which can lead to
o e s o p h a g e a l v a r i c e s
(swollen veins in
the oesophagus) and
a s c i t e s
(collection
of fluid in the abdomen).
Enlargement of the liver is a
common symptom of
l e u k a e m i a s
and
l y m p h o m a s . L i v e r f a i l u r e
(complete loss
of liver function) may be caused by
acute hepatitis, poisoning, or cirrhosis.
INVESTIGATION
Disorders of the liver may be
investigated by
liver biopsy
(removal
of a tissue sample for examination),
liver-function tests,
and
liver imaging
(which includes
ultrasound scanning,
CTscanning,
and MRI).
e y e s ,
d u e t o a c c u m u l a t i o n o f t h e b i l e
p i g m e n t
b i l i r u b i n
)
a n d
a s c i t e s
( e x c e s s
f l u i d i n t h e a b d o m
e n ) .
DIAGNOSIS AND TREATMENT
B l o o d t e s t s ( s e e
l i v e r - f u n c t i o n t e s t s
)
m a y
b e u s e d t o a s s e s s l i v e r f u n c t i o n , w h i c h
c a n b e d i s t u r b e d b y c a n c e r . T u m o u r s a r e
o f t e n d e t e c t e d b y
u l t r a s o u n d s c a n n i n g
,
C T
s c a n n i n g
,
o r
M R I
; d i a g n o s i s m a y b e c o n -
f i r m e d b y
l i v e r b i o p s y
( t i s s u e s a m p l i n g ) .
A h e p a t o c e l l u l a r c a r c i n o m a c a n s o m e -
t i m e s b e c u r e d b y t o t a l r e m o v a l o f t h e
t u m o u r a n d a s u r r o u n d i n g a r e a o f n o r -
m a l t i s s u e . I n o t h e r c a s e s ,
a n t i c a n c e r d r u g s
c a n h e l p t o s l o w t h e t h e d i s e a s e ’s p r o g r e s s .
I t i s u s u a l l y n o t p o s s i b l e t o c u r e s e c o n d -
a r y l i v e r c a n c e r , b u t a n t i c a n c e r d r u g s o r ,
i n s o m e c a s e s , r e m o v a l o f a s o l i t a r y
m e t -
a s t a s i s
( s e c o n d a r y
c a n c e r o u s
t u m o u r )
m a y s i g n i f i c a n t l y i m p r o v e t h e o u t l o o k .
liv e r, c ir r h o s is o f
S e e
c i r r h o s i s
.
liv e r d is e a s e , a lc o h o lic
D a m a g e
t o
t h e
l i v e r
r e s u l t i n g
f r o m
e x c e s s i v e
a l c o h o l
c o n s u m p t i o n . A l c o h o l -
r e l a t e d l i v e r d i s e a s e i n c r e a s e s t h e r i s k o f
d e v e l o p i n g
l i v e r c a n c e r
.
T h e l o n g e r t h a t h e a v y a l c o h o l
c o n -
s u m p t i o n g o e s o n , t h e m
o r e s e v e r e t h e
d a m a g e . T h e i n i t i a l e f f e c t i s t h e f o r m
a -
t i o n o f f a t g l o b u l e s i n s i d e l i v e r c e l l s , a
c o n d i t i o n c a l l e d f a t t y l i v e r , f o l l o w e d b y
a l c o h o l i c
h e p a t i t i s
( l i v e r i n f l a m m a t i o n ) .
D a m a g e p r o g r e s s e s t o
c i r r h o s i s
( s c a r r i n g
o f l i v e r t i s s u e ) , r e s u l t i n g i n s e v e r e s t r u c -
t u r a l d a m a g e e v e n t u a l l y l e a d i n g t o l o s s
o f l i v e r f u n c t i o n .
L i v e r - f u n c t i o n t e s t s
s h o w a c h a r a c t e r -
i s t i c p a t t e r n o f a b n o r m
a l i t i e s , a n d
l i v e r
b i o p s y
( t i s s u e s a m p l i n g ) m a y b e n e e d e d
t o a s s e s s t h e s e v e r i t y o f d a m a g e . T h e r e i s
n o p a r t i c u l a r t r e a t m e n t , b u t a b s t i n e n c e
f r o m
a l c o h o l p r e v e n t s f u r t h e r d a m a g e .
T r e a t m e n t f o r
a l c o h o l d e p e n d e n c e
m a y
b e r e q u i r e d i n s o m
e c a s e s .
liv e r fa ilu re
S e v e r e
i m
p a i r m
e n t
o f
l i v e r
f u n c t i o n
t h a t d e v e l o p s s u d d e n l y ( a c u t e l i v e r f a i l -
u r e )
o r a t t h e f i n a l s t a g e s o f a c h r o n i c
l i v e r
d i s e a s e
( c h r o n i c
l i v e r
f a i l u r e ) .
B e c a u s e
t h e
l i v e r b r e a k s
d o w n
t o x i n s
i n t h e
b l o o d ,
l i v e r
f a i l u r e
c a u s e s
t h e
l e v e l s o f t h e t o x i n s t o r i s e , a f f e c t i n g t h e
f u n c t i o n i n g
o f o t h e r
o r g a n s ,
p a r t i c u -
l a r l y t h e b r a i n .
SYMPTOMS
S y m p t o m s o f a c u t e l i v e r f a i l u r e
d e v e -
l o p r a p i d l y ; t h e y m a y i n c l u d e i m p a i r e d
m e m o r y , a g i t a t i o n , a n d c o n f u s i o n , f o l -
l o w e d b y d r o w s i n e s s . T h e f u n c t i o n i n g
o f o t h e r o r g a n s m a y a l s o b e c o m
e i m
-
p a i r e d , a n d t h e c o n d i t i o n m a y l e a d t o
c o m a
a n d d e a t h .
F e a t u r e s o f c h r o n i c l i v e r f a i l u r e d e v e -
l o p m
u c h m o r e g r a d u a l l y . T h e y i n c l u d e
j a u n d i c e
;
i t c h i n g ;
e a s y
b r u i s i n g
a n d
b l e e d i n g ; a s c i t e s ( s w o l l e n a b d o m e n d u e
t o a c c u m u l a t e d f l u i d ) ; r e d p a l m s ; a n d ,
i n
m a l e s ,
g y n a e c o m a s t i a
( e n l a r g e d
b r e a s t s )
a n d
s h r u n k e n
t e s t e s .
C h r o n i c
l i v e r
f a i l u r e
m a y
s u d d e n l y
d e t e r i o r a t e
i n t o a c u t e l i v e r f a i l u r e .
TREATMENT
A c u t e l i v e r f a i l u r e r e q u i r e s u r g e n t h o s -
p i t a l
c a r e . A l t h o u g h
n o
t r e a t m e n t
c a n
r e p a i r d a m a g e t h a t h a s a l r e a d y o c c u r r e d
i n a c u t e o r c h r o n i c l i v e r f a i l u r e , c e r t a i n
m e a s u r e s ,
s u c h
a s
p r e s c r i b i n g
d i u r e t i c
472
previous page 471 BMA A Z Family Medical Encyclopedia   2004 read online next page 473 BMA A Z Family Medical Encyclopedia   2004 read online Home Toggle text on/off