Management of Primary Biliary ...

Management of Primary Biliary Cirrhosis, Lekarski, Choroby zakaźne

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AASLD Practice Guidelines
Management of Primary Biliary Cirrhosis
E. J
ENNY
H
EATHCOTE
Primary biliary cirrhosis (PBC) is a presumed autoim-
mune disease of the liver, which predominantly affects
women once over the age of 20 years. Most cases are
diagnosed when asymptomatic (60%). The antimitochon-
drial antibody is present in serum in most, but not in all,
patients with PBC. The disease generally progresses slowly
but survival is less than an age- and gender-matched general
population. The symptomatic patient may have fatigue,
generalized pruritus, portal hypertension, osteoporosis,
skin xanthomata, fat soluble vitamin deficiencies, and/or
recurrent asymptomatic urinary tract infections. Many
nonhepatic autoimmune diseases are found in association
with PBC and may prompt initial presentation. To date,
immunosuppressive therapy has not been shown to prolong
survival in PBC. The hydrophilic bile acid, ursodeoxycholic
acid (UDCA), has been shown when given in a dose of 13 to
15 mg/kg daily for up to 4 years to delay the time to liver
transplantation or death. This therapy also causes a signifi-
cant improvement of all the biochemical markers of choles-
tasis but has no beneficial effects on any of the symptoms or
associated disorders. Treatment with UDCA does not obvi-
ate the need for liver transplantation. Therapies to prevent
complications arising from malabsorption, portal hyperten-
sion, and/or osteoporosis are required as well. Good control
of pruritus can be achieved in most patients. PBC is
diagnosed with increasing frequency, but the agent(s) respon-
sible for this slowly progressive destruction of the interlobu-
lar bile ducts remains elusive and hence a specific therapy
remains unavailable. (H
EPATOLOGY
2000;31:1005-1013.)
are designed to aid the practicing physician in diagnosing
PBC, establishing the severity of the disease, recognizing the
direct complications of PBC and its associated disorders, and
finally, to advise on the therapies available that will benefit
patients from a symptomatic, preventative, and therapeutic
standpoint. As such, what is written should be taken as
guidelines and not ‘‘standards of care.’’ The strength of each
recommendation is categorized based on the quality of
evidence in the literature according to the rating system
indicated in Table 1.
Where appropriate throughout this report, categories A
through E have been attached to the recommendations to
indicate the benefit to be expected from following the
suggested recommendations (Table 2).
INTRODUCTION
PBC is a presumed autoimmune disease of the liver, which
predominantly affects middle-aged women.
2
PBC is caused by
granulomatous destruction of the interlobular bile ducts,
which leads to progressive ductopenia. The consequent
cholestasis is generally slowly progressive, and fibrosis,
cirrhosis, and eventual liver failure occur.
Currently, the diagnosis of PBC most often is made when
the patient is still asymptomatic, with abnormal liver biochem-
istry and/or antimitochondrial antibodies (AMA) noted in
blood at the time of a routine check-up or as part of the
work-up for an associated disorder.
DIAGNOSIS OF PBC
PREAMBLE
These guidelines have been written to assist physicians in
the recognition, diagnosis, and management of patients with
primary biliary cirrhosis (PBC). The data provided have been
obtained from peer-reviewed articles published since the
hallmark for this disease, namely the antimitochondrial
antibody, was recognized in the early 1960s. These guidelines
GT]) is the most common bio-
chemical abnormality in PBC. Although at diagnosis few
patients have elevation of their serum bilirubin; when pres-
ent, it should be the conjugated fraction that is elevated.
Elevation of serum bilirubin is a late phenomenon and an
excellent predictor of survival.
3
As in any patient with
chronic cholestasis, total serum cholesterol may be elevated.
g
glutamyl transpeptidase; IF, immunofluorescence;
ANA, antinuclear antibodies; SMA, smooth muscle antibodies; UDCA, ursodeoxycholic
acid; HRT, hormone replacement therapy.
From the Division of Gastroenterology, University of Toronto, The Toronto Hospital,
Toronto, Ontario, Canada.
Received January 24, 2000; accepted January 27, 2000.
Written under the Auspices of The American Association for the Study of Liver
Diseases Practice Guidelines Committee.
Address reprint requests to: Jenny Heathcote, M.D., Division of Gastroenterology,
University of Toronto, University Health Network, The Toronto Western Hospital, WW
4-828, 399 Bathurst Street, Toronto, Ontario, Canada M5T 2S8. E-mail:
jheathcote@msn.com; fax: 416-603-9195.
Copyright
g
GT,
g
Radiologic Assessment of the Bile Ducts
Good ultrasound examination of the liver and biliary tree is
mandatory in all patients with biochemical evidence of
cholestasis. If the biliary system appears normal by ultra-
sound and the AMA test is positive (see below), no further
radiologic delineation of the bile ducts is necessary. If the
diagnosis of PBC is uncertain or a sudden rise in the serum
bilirubin takes place, cholangiography may be necessary, but
this should not be a first-line investigation.
4
AMA Testing
The major hallmark of PBC is the presence of AMA in
serum.
5,6
The simplest and most economical test is immuno-
2000 by the American Association for the Study of Liver Diseases.
0270-9139/00/3104-0027$3.00/0
doi:10.1053/he.2000.5984
1005
Biochemical Tests
Elevation in serum alkaline phosphatase (ALP) (with
confirmation of hepatic origin by checking the gamma
glutamyl transpeptidase [
Abbreviations: PBC, primary biliary cirrhosis; AMA, antimitochondrial antibodies;
ALP, alkaline phosphatase;
r
1006
HEATHCOTE
H
EPATOLOGY
April 2000
T
ABLE
1. Quality of Evidence on Which Recommendation Is Based
Grade
Definition
AMA-Negative PBC
Several investigators have reported patients who clinically,
biochemically, and histologically have all the features of
primary biliary cirrhosis but their sera consistently tested
negative for AMA both by IF and with the most specific
immunoblotting techniques.
16-20
These patients have been
described as having ‘‘immune cholangitis’’ or ‘‘autoimmune
cholangitis.’’ Most likely they are cases of PBC, except their
non–organ-specific antibody profile is more in keeping with
that of autoimmune hepatitis;
i.e.
, they have high titer ANA
and/or SMA. The natural history and associated autoimmune
conditions in AMA-positive and AMA-negative PBC appear to
be exactly the same. However, because the autoantibody
profile of AMA-negative PBC is like that of autoimmune
hepatitis, confusion as to the correct diagnosis may arise and
careful review of the liver biochemical pattern (ALP and
g
I
Evidence from multiple well-designed randomized controlled
trials each involving a number of participants to be of suffi-
cient statistical power.
II
Evidence from at least one large well-designed clinical trial with
or without randomization, from cohort or case-control ana-
lytic studies, or well-designed meta-analysis.
III
Evidence based on clinical experience, descriptive studies, or
reports of expert committees.
IV
Not rated
NOTE. These standardized guidelines of the Practice Guideline Commit-
tee of the American Association for The Study of Liver Diseases have been
modified from the Categories of the Infectious Diseases Society of America’s
Quality Standards.
1
fluorescence (IF) using rat stomach and kidney.
5
In PBC
patients, AMA is generally present in high titer. Low-titer
AMA (
GT) and the histology (bile duct injury) is necessary. It is
extremely unusual for a truly positive AMA test to be found in
a patient with otherwise obvious autoimmune hepatitis.
21
A
retrospective chart review of 200 patients diagnosed histologi-
cally as having the typical findings of PBC on liver biopsy
showed that 12% had no autoantibody markers.
22
1:40) may not be specific and may disappear on
retesting.
7
In addition, false-positive tests may occur due to
misreading of the localization of the fluorescence pattern or
failing to dilute the sera prior to testing.
8
Because the specific
substrates for AMA have been identified as being the inner
mitochondrial enzymes of the 2-oxo-acid dehydrogenase
family, more specific and sensitive tests for AMA using the
enzyme-liked immunosorbent assay technique and immuno-
blotting have been developed.
6
The sensitivity and specificity
of AMA for PBC are both greater than 95%, although there is a
report that if all immunoglobulin fractions are examined for
antibodies to the several different members of 2 oxo-acid
dehydrogenase family of mitochondrial enzymes, all PBC sera
test positive.
9
There have been varying reports on prevalence
of AMA in family members of index cases,
10,11
some of which
suggest that the figures are higher than in the blood donor
population where AMA are rarely found.
12
Antinuclear anti-
bodies (ANA) and/or smooth muscle antibodies (SMA) are
found in the serum of one third of patients with otherwise
clear-cut PBC.
13
,
Immunoglobulins
The pattern of the immunoglobulin fractions in PBC is
characterized by an elevation of IgM in particular.
23
IgA levels
are usually normal but PBC has been described in persons
with IgA deficiency.
24
However, testing for the pattern of
immunoglobulins is probably only necessary in doubtful
cases of PBC. In AMA-negative PBC, the IgG fraction is
elevated whereas the IgM fraction is less likely to be in-
creased.
18,20
1:40 and the typical
symptoms and biochemical abnormalities, a liver biopsy may
not be essential to make the diagnosis of PBC. Nevertheless,
the histological features of PBC, particularly in noncirrhotic
patients, are very specific. Although different histological
stages of the disease (stage 1 through 4) have been well
described, it is not unusual to find features typical of several
different stages in the one biopsy specimen. Because this
disease predominantly affects bile ducts, it is essential that
the liver specimen have an adequate number of portal tracts
for the pattern of bile duct damage to be accurately assessed.
25
Stage 1 disease is characterized by a portal hepatitis with
granulomatous destruction of the bile ducts, although granu-
loma are often not seen. Stage 2 is characterized by periportal
hepatitis and bile duct proliferation. The presence of fibrous
septa or bridging necrosis is classified as stage 3 and cirrhosis
as stage 4.
26
The presence of fibrosis or cirrhosis does indicate
a worse prognosis than if no fibrosis is seen on biopsy.
27
If the AMA is negative or in low titer (
$
1:40 by IF) with
normal alkaline phosphatase values.
14
All but 2 had abnormal
liver histology, and in 12 the findings were diagnostic. A
10-year follow-up of these patients reported that 24 of the
surviving 29 subjects remained AMA positive. All 24 devel-
oped biochemical evidence of cholestasis and 22 became
symptomatic.
15
$
T
ABLE
2. Categories Reflecting the Evidence to Support the Use of a
Guideline Recommendation
Category
Definition
1:40) or if the
patient has a biochemical picture with prominent elevation of
transaminase levels,
i.e.
‘‘hepatitic,’’ or has been taking
potentially hepatotoxic drugs, a liver biopsy is essential to
confirm or refute the diagnosis of PBC. There are many other
causes of chronic, intrahepatic cholestasis, mostly due to
vanishing intrahepatic bile ducts (some may involve the
larger ducts as well,
i.e.
, primary sclerosing cholangitis).
28
In
late stage cirrhosis, it may be impossible to make a confident
histological diagnosis of PBC.
,
A
Survival benefit
B
Improved diagnosis
C
Improvement in quality of life
D
Relevant pathophysiologic parameters improved
E
Impacts cost of health care
NOTE. These standardized guidelines of the Practice Guideline Commit-
tee of the American Association for the Study of Liver Diseases have been
modified from the categories of the Infectious Diseases Society of America’s
Quality Standards.
1
Liver Biopsy
In a patient who has an AMA of
AMA Positive With Normal Liver Biochemistry
There is one small study of the liver pathology in 29
asymptomatic AMA-positive subjects (all
H
EPATOLOGY
Vol. 31, No. 4, 2000
HEATHCOTE
1007
F
IG
. 1. Diagnosis of PBC. Abbreviations: Igs, immunoglobulins; VBDS,
vanishing bile duct syndromes.
there is an association with sleep disorder and depression.
However, which symptom leads to the other remains un-
known.
2.
Pruritus
. The pathogenesis of pruritus in cholestasis
remains unknown. Objective studies indicate there is a
circadian rhythm to pruritus due to cholestasis.
31
The symp-
tom diminishes with time from diagnosis.
32
When present,
pruritus may be so severe as to cause sleep deprivation and
even severe emotional disturbance sufficient to necessitate
liver transplantation. This may been seen in a patient who
otherwise has good liver function.
3.
Portal hypertension
. Patients may, on occasion, present
de novo
with a variceal hemorrhage. This may be caused by
noncirrhotic portal hypertension
33
or secondary to cirrhosis.
Complications of variceal hemorrhage are not predicted by
standard prognostic indices.
4.
Metabolic bone disease
. Both decreased osteoblastic activ-
ity and increased osteoclastic activity contribute to the
development of osteoporosis in PBC patients.
34
Patients may
present with osteoporosis and yet be asymptomatic from their
liver disease. The relative risk of osteopenia,
i.e.
, osteoporosis
greater than expected for gender and age, is 4.4.
35
Because
patients with osteoporosis without fractures have a normal
ALP, the presence of an increased ALP in patients with
osteoporosis should raise a suspicion of PBC. Genetic factors
may also play a role in the pathogenesis of osteoporosis in
PBC.
35,36
Metabolism of vitamin D is normal in PBC, but
malabsorption of both calcium and vitamin D may occur.
Pancreatic insufficiency and celiac disease, which are also
seen in PBC
37-39
may further aggravate malabsorption.
5.
Xanthomata
are much more common in PBC than with
any other chronic cholestatic disease in adults. They predomi-
nantly occur around the eyes (called xanthelasma), although
they may be found on the palms (often painful), buttocks,
and heels. They are not uniquely associated with hypercholes-
terolemia although hypercholesterolemia is common in PBC.
They generally spontaneously disappear with progression of
disease.
6.
Fat soluble vitamin malabsorption
. When biliary secre-
tion of bile acids is insufficient,
i.e.
, below the critical micellar
volume in the duodenum, malabsorption of both fat and fat
soluble vitamins will take place. Serum values for vitamin A
and E have been shown to be low in a minority of patients
with primary biliary cirrhosis prior to jaundice.
40
Night
blindness is infrequently documented. Neurological impair-
ment secondary to vitamin E deficiency is much more
common in children than adults with chronic cholestasis,
although electromyograph changes have been found in PBC
patients with low serum tocopherol levels.
41
Osteomalacia is
now very rarely seen in PBC as a liver transplant is performed
in most patients before the development of this complication
of prolonged deep jaundice.
7.
Urinary tract infections
. Recurrent, but often asymptom-
atic, urinary tract infections may be found in up to 19% of
women with primary biliary cirrhosis.
42
8.
Malignancy in PBC
. There have been two reports that
suggest that the rate of carcinoma of the breast is increased in
Recommendations Regarding the Diagnosis of PBC (Fig. 1)
1. In patients with otherwise unexplained elevation in
alkaline phosphatase (normal bile ducts on ultrasound),
serum testing for AMA is appropriate (III B).
2. The diagnosis of PBC can be made with confidence in a
patient with high-titer AMA (
$
1:40) with a normal
serum alkaline phosphatase, should be followed prospec-
tively with annual reassessment of biochemical testing (III B).
4. In patients with otherwise unexplained elevation in
alkaline phosphatase (normal bile ducts on ultrasound) and a
negative AMA test, ANA, SMA, and immunoglobulins should
be tested and a liver biopsy should be performed (III B).
$
MANIFESTATIONS OF PBC (Fig. 2)
1.
Fatigue
is present in up to 70% of PBC patients.
29,30
It
does not correlate with the severity of the liver disease but
F
IG
. 2. Manifestations of PBC.
1:40) and a cholestatic
pattern of liver biochemistry in the absence of an alternative
explanation. A liver biopsy may also be considered (III B).
3. Patients who are AMA positive (
1008
HEATHCOTE
H
EPATOLOGY
April 2000
women with PBC,
43,44
but this has not been confirmed in two
other studies.
45,46
It is likely that the perceived increased
prevalence of breast cancer in PBC patients is due to an
increase in the rate of detection, because patients are regu-
larly undergoing medical examination. In contrast, two
recent studies both indicated that hepatocellular carcinoma
complicates late-stage PBC just as it does other causes of
cirrhosis.
47,48
One report suggests that this complication is
more common in men with PBC. The overall incidence of
hepatocellular carcinoma in a sample of 273 PBC patients
with stage III/IV disease was found in one study to be 5.9%
(4.1% in women but 20% in men with advanced disease).
47
symptomatic patients. There have been 4 large trials,
32,61-63
and the raw data from 3 of these trials have been combined as
each used the same formulation of UDCA in the same dose,
i.e.
, 13 to 15 mg/kg/d.
64
The analysis of these data collected
from 548 patients shows that UDCA therapy leads to a
significant increase in survival after up to 4 years of therapy,
as judged by time to liver transplantation.
In the fourth large randomized controlled study in PBC
patients using a slightly lower dose of UDCA (10 mg/kg/d),
the investigators suggest that UDCA is less effective in
patients whose bilirubin is greater than 2 mg/dL at baseline.
63
However, the combined analysis of the other 3 large studies
does not suggest that this is the case.
64
In fact, the greatest
benefit is seen in those with the most severe disease, because
predictably, more events were observed in patients with
severe rather than with mild disease.
UDCA treatment is associated with a marked improvement
in serum biochemical markers of cholestasis,
i.e.
, bilirubin,
ALP, and
MANIFESTATIONS OF PBC—
ASSOCIATED DISORDERS (Fig. 2)
The prevalence of autoimmune disorders found in associa-
tion with PBC is reported in several large series.
49-51
1.
Thyroid dysfunction
is a common autoimmune disorder
associated with PBC and its presentation often predates the
diagnosis of PBC.
52
2. If
sicca symptoms
are sought by direct questioning, they
are present in up to 70% of PBC patients.
53
Symptoms related
to the sicca syndrome include xerophthalmia, xerostomia,
dental caries, dysphagia, tracheobronchitis, and dyspareunia.
If a superimposed motility problem is also present, asymptom-
atic or symptomatic reflux causing esophagitis and possible
stricture formation may develop. This is more common in
patients with the CREST syndrome.
3.
CREST
(calcinosis cutis, Raynaud’s phenomena, esopha-
geal dysmotility, and telangiectasia) in its complete form is
rarely seen in PBC patients.
54
4.
Raynaud’s syndrome
alone is more common and is
particularly troublesome for patients living in cold climates.
5.
Rheumatoid factor
is present in the serum in 25% of
patients with PBC, but symptomatic arthritis is less com-
mon.
55
6.
Celiac disease
, often asymptomatic, is present in 6% of
PBC patients.
40
7.
Inflammatory bowel disease
, namely ulcerative colitis
may be uncommonly seen in association with PBC.
56
GT, including a fall in serum cholesterol levels.
Treatment does not seem to benefit the symptom of fatigue
and has a variable effect on pruritus,
32
no benefit on
osteoporosis,
65
but some benefit on the development of portal
hypertension.
66
Side effects from UDCA use are rare, the most
common being diarrhea; it is an extremely safe drug. The
biliary enrichment with UDCA is the same whether it is taken
in divided doses or as a single dose.
67
Compliance is likely
better with the latter regime. However, although UDCA slows
the progression of PBC in treated patients, its use does not
lead to resolution of the disease. Progressive disease contin-
ues to require liver transplantation.
Treatment with UDCA reduces the rate of development of
esophageal varices, but it does not reduce the rate of bleeding
from varices.
68
Small trials of combination therapy using UDCA with
methotrexate, colchicine, or prednisolone, have been re-
ported but have not shown any increased efficacy over UDCA
therapy. The sample sizes of these studies were too small to
adequately evaluate efficacy.
69-71
Recommendations.
Appropriately selected patients with PBC
with abnormal liver biochemistry should be advised to take
UDCA, 13 to 15 mg/kg daily in either divided doses or as a
single daily dose. If cholestyramine is used, 4 hours should
elapse between cholestyramine intake and UDCA administra-
tion (I A, D, E).
SPECIFIC THERAPY FOR PRIMARY BILIARY CIRRHOSIS
All PBC patients with abnormal liver biochemistry should
be considered for specific therapy.
Immunosuppressive Therapy
As primary biliary cirrhosis appears to be an autoimmune
disease, several immunosuppressive drugs have been tested
in randomized controlled trials and none have been shown to
be of great benefit. However, only two of the trials were
sufficiently large to accurately evaluate an effect on survival.
One trial was of azathioprine and the other of cyclospo-
rine.
72,73
Despite sample sizes of 248 and 349, neither trial
showed a beneficial effect of therapy on survival. Neither of
these drugs is without side effects. Cyclosporine use was
associated with a high withdrawal rate because of significant
effects on renal function and systemic blood pressure. There
has been one small randomized controlled trial of predniso-
lone in which a beneficial effect on the biochemical markers
of PBC was observed, but there was some deterioration in
bone mineral density.
74
Methotrexate, used in pilot studies only, has been said to
have beneficial effects on the symptoms and biochemical and
Ursodeoxycholic Acid Therapy
Bile duct destruction leads to the retention of hydrophobic
bile acids within the liver cell, and this most likely contrib-
utes to the gradual deterioration in liver function observed in
patients with primary biliary cirrhosis. Ursodeoxycholic acid
(UDCA) increases the rate of transport of intracellular bile
acids across the liver cell and into the canaliculus in patients
with both primary sclerosing cholangitis and PBC.
57
UDCA
treatment reduces intracellular hydrophobic bile acid levels
and thereby may have a cytoprotective effect on cell mem-
branes.
58,59
agent.
60
There have been many randomized controlled trials of
UDCA in PBC and all included both asymptomatic and
g
UDCA may also act as an immunomodulatory
H
EPATOLOGY
Vol. 31, No. 4, 2000
HEATHCOTE
1009
histological features of PBC.
75
However, one randomized
controlled trial of methotrexate therapy, suggested that even
at low doses (2.5 mg 3 times per week) methotrexate may be
toxic over a 6-year period.
76
Hence at the present time, there
is insufficient data to support the use of immunosuppressive
therapy in PBC.
terol levels may cause unnecessary anxiety, but retrospective
studies do not suggest an increase in atherosclerotic heart
disease in PBC.
87
Fractionation of the triglyceride fractions
show high-density lipoprotein levels to be greater than
low-density lipoprotein, and treatment with UDCA further
lowers low-density lipoprotein and raises high-density lipo-
protein values.
88
Liver Transplantation
PBC is a common indication for transplant.
77
There is some
evidence that PBC may recur in the allograft.
78,79
When it
does so, it is certainly a rare event, progresses only very
slowly, and is no reason for not recommending liver transplan-
tation.
Timing of Liver Transplantation.
The most reliable determi-
nants of prognosis in PBC are the height of the serum
bilirubin
3
and the Mayo risk score.
80
The Mayo risk score is calculated as R
5
0.871 log
e
(biliru-
MANAGEMENT OF COMPLICATIONS OF PBC (Fig. 3)
Symptomatic Treatment
Pruritus.
There is no evidence that standard topical thera-
pies for the pruritus of PBC are effective. The oral anion
exchange resin, cholestyramine, has been the mainstay of
therapy for pruritus associated with cholestasis. The original
study indicated that this anion-binding resin led to marked
improvement of the symptom of pruritus.
89
It may be that this
drug is most effective in those patients with an intact
gallbladder when taken before and after breakfast,
90
because
the greatest amount of bile is likely to be available for binding
at this time. Many patients find cholestyramine unpleasant to
take and constipating, and they often request other therapy.
Because this drug not only binds bile acids but also oral
medications, notably UDCA, thyroxin, digoxin, and oral
contraceptive hormones, it is advisable that at least 4 hours
should lapse between the taking of cholestyramine and any
other medication. This drug is effective within a few days of
starting treatment. Doses of cholestyramine should start at 4 g
daily and be increased, if the effect is not sufficient, to a
maximum of 16 g. It needs to be made clear to the patient that
the treatment should be taken daily for the best effect.
Rifampicin
is an enzyme-inducing antibiotic that was
fortuitously identified as an agent that improved pruritus in
cholestasis. A subsequent crossover trial indicated that the
drug caused good control of pruritus in PBC patients at doses
bin in mg/dL)
2.53 log
e
(albumin in g/dL)
1
0.039 age in
years
1
2.38 log
e
(prothrombin time in seconds)
1
0.859(edema score of 0, 0.5, or 1).
80
A recent report has reassessed the Mayo risk score taking
into consideration other factors found to be important in the
timing of transplantation in patients with chronic cholestatic
liver disease.
81
Neither the height of the serum bilirubin nor
Mayo risk score are invalidated by UDCA therapy.
82
Treat-
ment with UDCA before liver transplantation does not alter
the posttransplantation outcome.
83
Recommendation.
Liver transplantation in PBC is recom-
mended for liver failure (II A, C, D). Liver transplantation
may be recommended in appropriately selected patients for
(1) uncontrollable pruritus (IV C); and (2) severe osteoporo-
sis (IV C).
THE PROGRESSION OF PBC
The progression of PBC is extremely variable. Studies of
asymptomatic patients suggest that their survival is reduced
when compared with an age- and gender-matched popula-
tion.
84,85
The response to UDCA therapy is not uniform.
Those patients whose liver biochemistry returns to normal
may have a better outcome than those patients where
treatment has a less beneficial effect on serum biochemistry.
86
HYPERBILIRUBINEMIA IN PBC
Serum bilirubin level is a useful guide to subsequent
outcome and may be used to indicate time for transplanta-
tion. However, there are situations in which elevation in the
serum bilirubin may not be caused by progression of PBC.
They include Gilbert’s syndrome, sepsis, pregnancy/hormone
replacement therapy (HRT)/oral contraceptive pill, common
duct stones, untreated thyroid disease, hemolysis, and toxic
liver injury. Hence, a rise in bilirubin that does not appear to
be associated with other signs of deterioration in liver
function should prompt further investigation.
Once signs of liver failure are present,
i.e.
, ascites, hepatic
encephalopathy, and/or a coagulopathy that cannot be cor-
rected by supplemental vitamin K, deterioration in liver
function tends to be rapid. It is unusual, but not unknown,
for ascites to develop before the onset of jaundice.
HYPERCHOLESTEROLEMIA IN PBC
The total serum cholesterol may be elevated in patients
with PBC. It tends to decrease with disease progression and is
significantly reduced by treatment with UDCA. High choles-
F
IG
. 3. Management of the complications of PBC.
12
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