Patients with liver disease present with varying severity ranging from being asymptomatic with abnormal liver function tests to those patients with overt florid liver failure. This paper will review extrahepatic features of liver diseases.
Pavithra Indramohan, MD, Elie Aoun, MD
Allegheny Health Network, Division
of Gastroenterology, Pittsburgh, PA
INTRODUCTION
The liver is the largest organ in the body and conducts
a myriad of vital metabolic and excretory functions.
In addition, by virtue of its circulatory relationship
to the absorptive surface of the gastrointestinal tract,
the liver is the initial site where ingested materials
entering via the gastrointestinal tract, such as drugs
and bacterial metabolites are processed. Hepatocytes
perform the function of homeostasis.1 Dysregulation
of the liver or hepatocytes thus produces clinical
effects that are limited not only to the liver, but can
also cause derangement in the internal mileu, thereby
contributing significantly to mortality and morbidity in
liver disease patients. The clinical syndrome produced
by hepatic injury may include systemic manifestations
and evidence of injury not limited only to the liver. It
is therefore essential to recognize the various extra-
hepatic features of liver diseases for timely management
of these disorders. Patients with liver disease present
with varying severity ranging from being asymptomatic
with abnormal liver function tests to those patients
with overt florid liver failure. This paper will review
extrahepatic features of liver diseases.
Effects of Liver Diseases on the Heart
In patients with cirrhosis, there is increased
arteriovenous (AV) shunting thereby increasing
the resting cardiac output, left ventricular diastolic
diameter, and mean velocity of the left ventricular
wall. There is also decreased peripheral resistance and
oxygen consumption related to AV shunting.2 However,
these effects are reversible after transplantation. Long-
term estrogen and anabolic steroids use may aggravate
preexisting vasculopathy, inducing sinusoidal dilation
and subsequent peliosis hepatis and should be considered
in the differential of high output failure in liver disease.3
The prevalence of myocardial infarctions is found
to be lower in cirrhotic patients than in the general
population. For mechanisms that remain unclear but
are probably related to cholesterol metabolism, there
is a protective effect on atherosclerosis in patients
with cirrhosis, with exceptions being in patients with
nonalcoholic steatohepatitis (NASH) and hepatitis
C virus (HCV)-related cirrhosis.4,5 It has been found
that HCV is an independent risk factor for accelerated
atherosclerosis in cirrhotic patients. Similarly, it is
reported that the prevalence of all coronary artery
disease risk factors are significantly higher in NASH-
related cirrhotic patients.6
There is paucity of data regarding the incidence
of HCV infection in non-ischemic cardiomyopathy,
although the association of dilated and hypertrophic
cardiomyopathies with HCV have been reported widely.
In some genetically predisposed individuals, HCV
core protein may damage the myocardium through
either direct or indirect immunological mechanisms.7,8
Fibrinous pericarditis, characterized by the presence
of fibrinous exudates in the pericardial sac that are
sometimes accompanied by a small amount of serous
effusion, has also been described in patients with
cirrhosis, although the underlying pathophysiology is
poorly understood. It has been found that pericarditis
can occur even in the absence of uremia as a result of
decompensated liver disease.9
Effects of Liver Diseases on the Respiratory System
Patients with liver diseases may exhibit dyspnea
due to a variety of cardiopulmonary alterations.
Hepatopulmonary syndrome (HPS) and portopulmonary
hypertension (PPHTN) are two pulmonary vascular
complications of liver disease manifesting as dyspnea.
A careful evaluation of concomitant symptoms, physical
examination, pulmonary function testing including an
arterial blood gas analysis, echocardiographic imaging,
and hemodynamic studies are useful for differentiating
between these conditions and is crucial for selecting
transplant candidates.10 HPS, occurring in 5%-32%
of cirrhotic patients, is a triad of decompensated liver
disease, arterial deoxygenation due to pulmonary gas
exchange abnormalties, and evidence of intrapulmonary
vascular dilatation (IPVD).11 Arterial desaturation (a
resting PA-a,O2 ≥15mmHg and ≥ 20 mmHg in patients
64 yrs) is due to increased intrapulmonary shunting
(99Tc MAA shunting index > 6%) without evidence
of pulmonary arterial hypertension. Intrapulmonary
vascular dilatation can be diagnosed by transthoracic
contrast enhanced echocardiography (CE TTE),
technetium 99m labeled macroaggregated albumin
(99Tc MAA) scan and pulmonary arteriography.
Contrast enhanced transthoracic echocardiography is
considered the gold standard for the diagnosis of HPS
with detection of microbubbles within the left atrium
considered to be a positive CEE.11,12 Orthotopic liver
transplant can be considered in severe cases and is the
most effective treatment.13
PPHTN is associated with portal hypertension
without evidence of intrapulmonary shunting (99Tc
MAA < 6%) and intravascular pulmonary vascular
dilation differentiating it from HPS. Although the
mechanism of PPHTN remains unclear, it is thought to
be due to accumulation of under-metabolized vasoactive
substances in the pulmonary circulation. Orthotopic
liver transplantation can worsen PPHTN and can
lead to acute right ventricular failure. It is therefore
contraindicated in patients with PPHTN, which makes
distinguishing HPS from PPHTN critical prior to liver
transplant.14,15
Chronic HCV is associated with idiopathic
pulmonary fibrosis and the cumulative rate of
development is 0.9% at 20 years after HCV infection.16
This is evidenced by the higher frequency of HCV
markers in IPF patients, an increase in lymphocyte and
neutrophil numbers in bronchoalveolar lavage of HCV
chronic infection patients.17
Effects of Liver Diseases on the Nervous System
The relationship between the functional status of
the liver and that of the brain has been known for
centuries.18 There are both central and peripheral
neurological manifestations of liver diseases. For the
purpose of understanding the central nervous system
presentations, hepatic encephalopathy related and
non hepatic encephalopathy-related changes will be
reviewed.
Hepatic Encephalopathy Associated Central Nervous System Damage
Hepatic encephalopathy is a spectrum of neuropsychiatric
damage ranging from inversion of sleep rhythm to
deep coma. It can occur both in acute or chronic liver
diseases. It is widely thought that the pathogenesis of
hepatic encephalopathy is multifactorial. Currently,
the two factors considered to be most important in
pathogenesis are raised brain concentration of ammonia
and increased GABA mediated neurotransmission.
Ammonia is normally metabolized by cerebral astrocytes
by converting glutamate to glutamine. However in
hepatic encephalopathy, due to excess ammonia, there
is an excess production of glutamine that causes the
astrocytes to swell resulting in the neuropsychiatric
manifestations of hepatic encephalopathy.19 Potential
mechanisms for increased inhibitory neurotransmitter
GABA in hepatic encephalopathy include increased
availability of GABA in synaptic clefts or increased
blood to brain transfer of GABA and increased brain
concentrations of natural benzodiazepine receptor
agonist ligands.20,21 Hepatic encephalopathy has been
classified into 4 stages based on the severity of the
symptoms (Table 1). Stage I is the mildest form and
includes symptoms such as mild confusion, and Stage
IV is the most advanced and severe form, which
includes coma.22,23
Precipitating factors for hepatic encephalopathy
include hypokalemia, hyponatremia, metabolic
alkalosis, hypoglycemia, gastrointestinal bleeding,
constipation, sedatives, tranquilizers, infection and
portosystemic shunts (spontaneous, surgical, TIPS).24
Asterixis or “liver flap” is often present in the early
stages of hepatic encephalopathy. Asterixis consists of
infrequent involuntary flexion-extension movements
of the hand (one flap every one to two seconds), which
may result in part from an impairment of the normal
inflow of joint position sense to the brain stem reticular
formation. Asterixis should be classified as a negative
myoclonus rather than a tremor.20
Recognizing and treating hepatic encephalopathy
is important, because data from the Healthcare Cost
and Utilization Project (HCUP) show that hepatic
encephalopathy is associated with substantial healthcare
utilization and costs.25 Some management strategies
include: 1) dietary protein restriction to reduce the
ammonia load, 2) non absorbable disaccharides, 3)
gut antibiotics like rifaximin, 4) branched chain AA,
and 5) use of the GABA inhinitor, flumenazil. Non-
absorbable disaccharides were shown to be inferior to
antibiotics in reducing ammonia levels, but there was
no significance in mortality between the two treatment
groups.26 Data suggest a significant improvement in
cognitive function following liver transplantation, but
patients do not return to normal.
Acquired (non-Wilsonian) hepatocerebral
degeneration (AHCD) is a clinico-pathological
syndrome of brain dysfunction resulting from repeated
attacks of hepatic encephalopathy.27
Non-Hepatic Encepahalopathy Related Central Nervous System Damage
Under this entity, Wilson’s disease is the best known.
Others include congenital diseases like Reye’s
syndrome, congenital hyperammoniemia, kernicterus,
galactosemia, porphyrias, Zellweger syndrome.20
Wilson’s disease is an autosomal recessive
neuropsychiatric disorder that occurs due to excessive
accumulation of copper in various organs, particularly
the liver and brain. Psychiatric manifestations of
Wilson’s disease are protean, but are predominantly
personality changes. Four basic categories of disturbance
have been described: behavioral/personality, affective,
schizophrenia-like, and cognitive dysfunction. The
neuropsychiatric manifestations such as dysarthria,
dyspraxia, ataxia, a tremor-rigidity syndrome
and psychoses, and progressive extrapyramidal
neurological disorder are characteristic of Wilson’s
disease.28,29 Hepatitis A infection can also result in
encephalomyelitis.30 It is also reported that chronic HCV
infection results in neurocognitive damage secondary
to the neuroinvasion of microglia by HCV.31 Hepatic
myelopathy is characterized by spastic paraparesis
with minimal sensory involvement. It is mainly due
to symmetrical demyelination, predominantly of the
lateral pyramidal tracts, sometimes associated with
axonal loss from the cervical cord level. It is thought
to be secondary to nitrogenous products bypassing the
liver through the porto-caval shunt in advanced hepatic
encephalopathy.32
Gullian Barre syndrome is associated with HBV
and rarely in HCV infection due to immune complex
deposition in these infections.33 The precise incidence,
severity and characteristics of neuropathy, and the
relationship of neuropathy to different etiologies of liver
disease have not been defined. Peripheral neuropathy
may be observed in patients with cryogloblunemia in
HCV infection, and usually is a moderate axonal sensory
polyneuropathy. It is also seen in other conditions
like porphyrias and alcoholic liver diseases. Sensory
neuropathy is also a common manifestation of primary
biliary cirrhosis. This contributes to hyperesthesia
leading to itching seen in primary biliary cirrhosis. In
addition, autonomic dysfunction presenting as reduced
24-hour heart rate variability is also seen in primary
biliary cirrhosis.13, 34
Effects of Liver Diseases on the Skin
Understanding and recognizing skin changes that
can occur in patients with liver failure is essential, as
it often leads to prompt diagnosis and treatment of
the underlying liver disease. For instance, jaundice,
the cardinal sign of hyperbilirubinemia, is usually
seen when serum bilirubin levels exceed 2.5 or 3.0
mg/dL.35 The color of the skin typically reflects the
severity of the bilirubin elevation. Another sign of an
underlying liver disorder is evidence of xanthelasma,
which is a painless yellow soft plaque that occurs due
to localized deposition of cholesterol underneath the
skin usually beneath the eyelids. another skin-related
disorder occurring in patients with an underlying liver
condition include hyper-pigmentation or a slate-gray
discoloration of the skin, which occurs in cirrhosis, but
more specifically in hemochromatosis. This is due to
iron deposition in the skin and hence called as Bronze
diabetes. Hyper-pigmentation should be contrasted with
hypo-pigmented macules called Bier’s spots, which
can also occur in liver diseases, secondary to venous
stasis from damage to the small vessels. These however
disappear on pressure and limb elevation.35,36
Pruritus
Until recently, it was thought that pruritus caused during
liver disease was related to toxins deposited in the
skin. However, studies now suggest that neural events
originating from the CNS may cause pruritus. It has been
observed that the central opioidergic tone is increased in
cholestasis causing pruritus, and hence opiate antagonists
ameliorate the pruritus of cholestasis.37 In fact, studies
have demonstrated a striking opioid withdrawal-
like syndrome induced by the oral administration of
a potent opiate antagonist, which further illustrates
that increased central opioidergic tone is the cause of
pruritis in patients with chronic cholestatic liver disease.
Although pruritus is generally resistant to therapy, anion
exchange resin cholestyramine, rifampicin, and opioid
antagonist naltrexone have been used with varying
success. Plasmapharesis has been used successfully in
resistant cases, and liver transplantation has been shown
to ameliorate pruritus completely.38
Prurigo Nodularis
Another skin condition, prurigo nodularis, which
are intensly pruritic, firm, crusty nodules, have been
observed in patients with hepatitis C infection. These
nodules lead to itching, excoriation and diffuse scarring.
Corticosteroid cream, antihistamine, and low-dose
thalidomide, and tumor necrosis factor (TNF) antagonist
have been used to control symptoms.35
Lichen Planus
Also seen in patients with hepatitis C infection are lichen
planus, which are planar, polygonal, purplish pruritic
papules occurring anywhere on the body, but are most
prominent on the wrists and ankles. In approximately
85% of affected individuals, the papules usually resolve
by 18 months. A subtype of this skin disorder, called
lichen planopilaris, occurs on the scalp and results in
permanent hair loss.39
Vitiligo
Vitiligo is an autoimmune destruction of the
melanocytes, and it manifests as depigmented, irregular,
white patches. It occurs in primary biliary cirrhosis
and also in patients with hepatitis C infection who
are being treated with interferon. Interferon-induced
vitiligo resolves after treatment cessation.35 Porphria
Cutanea Tarda results from a deficiency of the hepatic
enzyme uroporphyrin decarboxylase. This causes a
photochemical reaction that generates reactive oxygen
species that activate uroporphyinogen deposited in the
skin, thus leading to the characteristic skin blistering.
In 50% patients with hepatitis C in sun-exposed areas,
as the blisters heal, keratin filled milial cysts develop
in these areas of ulceration.13,40
Dupuyntren’s Contracture
Dupuyntren’s contracture is the fibrotic thickening of
the palmar fascia, resulting in painless stiffness, curling
and loss of function of the involved fingers. Although
the pathogenesis is unknown, it is usually observed in
patients with alcoholic liver diseases. It is amenable to
correction by surgery, radiation, simvastatin, or N acetyl
cysteine. Facial lipodystrophy is also seen in alcoholic
liver disease due to malnutrition.17,41
Cutaneous Vascular Signs
The most common cutaneous vascular sign are
echymoses, which occur due to easy bruising secondary
to platelet function abnormalities in cirrhosis. Spider
vessel, usually in the area drained by the superior vena
cava. It is due to an accumulation of free estradiol in
patients with liver diseases causing these vessels to dilate
and is associated with coexisting gastric and esophageal
varices. Therefore, the presence of echymoses should
prompt the clinician for endoscopic work up in liver
disease.42 Papermoney skin, a random scattering of
needle-thin thread-like capillaries in the upper trunk
resembling American dollar bills, occurs in association
with spider angiomas. Palmar erythema is a crimson
discoloration of the palms and fingertips, more in the
hypothenar eminence occurring in liver disease. It is
thought to be secondary to localized increase in nitric
oxide and prostacyclins resulting in vasodilation and
erythema.36 Advanced liver disease can cause thinning
and loss of hair. Similarly, it can also cause thinning and
damage of the nails. It can lead to clubbing, onycholysis
and leuconychia. Terry’s nails, which is a ground glass
opacity of the proximal 2/3 of the nails can also occur
in patients with cirrhosis.35,43
Effects of Liver Diseases
on the Renal System
Renal manifestations in liver diseases could be hepatitis-
associated nephropathy or hepatorenal syndrome from
cirrhosis, and it is essential to differentiate both.
Hepatorenal Syndrome(HRS)
The incidence of HRS is close to 40 % after 5 years
of cirrhosis. Patients with ascites having dilutional
hyponatremia secondary to renal retention of sodium are
at an increased risk for HRS.44,45 Based on the rapidity of
progression of renal failure, they are classified as having
Type1 or type 2 failure. The predominant clinical feature
of patients with type 1 HRS is severe renal failure, and
that of patients with type 2 HRS is recurrent ascites. The
mechanism is due to increased splancic vasodilation in
portal hypertension. This leads to arterial underfilling,
triggering the vasoconstrictive compensatory
mechanisms including the renal vasculature, thereby
decreasing renal perfusion contributing to HRS.46 The
initial approach to these patients with renal failure,
begins with urinalysis. The diagnosis of HRS is being
made in the absence of parenchymal kidney disease,
proteinuria <500 mg/d with elevated creatinine in a
patient with cirrhosis with ascites in the absence of
shock. Treatment includes volume expansion and
vasoconstricting agents to improve the extremely
dilated splancic bed and to suppress the endogenous
renal vasoconstriction for improved renal circulation.
The survival expectancy is dependent on the type of
HRS and the severity of liver disease. Even with liver
transplant, the 3-year survival is lower in comparison
with those patients with no HRS. In type 1, hospital
survival is less than 10% and the expected median
survival time only 2 weeks. By contrast, patients with
type 2 have a much longer median survival time.44,45
Hepatitis Associated Renal Disease
Hepatitis B is directly associated with membranous
nephropathy and membranoproliferative
glomerulonephritis (MPGN). HBV-related MPGN is
due to immune complex deposition in the mesangium
and subendothelial space. Antiviral treatment with
lamivudine or interferon induces complete remission.47,48
Nephrotic syndrome secondary to HBV-related
membranous nephropathy resolves spontaneously in
children unlike in adults, which does not respond to
antiviral treatment either.13
The incidence of mixed cryoglobulinemia, MPGN
and membranous nephropathy is more common with
HCV than HBV. The pathogenesis of HCV related
cyroglobulinemic MPGN is due to glomerular damage
caused by immune complex deposition of HCV, IgG
and IgM rheumatoid factors.49 The combination
treatment of peginterferon and ribavarin has been
shown to effectively cause sustained virologic response,
resolution of proteinuria along with improvement in
creatinine levels. Rituximab has also been shown to be
successful in improving glomerular nephritis.50
Effects of Liver Diseases on the Blood
Platelet Abnormalities
Thrombocytopenia alone or in combination with other
cytopenias is the most common cytopenia associated
with liver disease and occurs in up to 77% of patients
with cirrhosis.51
Multiple mechanisms involving decreased
production and increased peripheral destruction
contribute to this abnormality. Thrombopoietin is
produced in the liver and it can be decreased in
liver failure along with a decreased function of the
synthesized platelets. Increased peripheral destruction
could be related to splenic sequestration or antibody
mediated as in HCV. High affinity binding of HCV to
platelet membrane with subsequent binding of anti-
HCV antibody with subsequent phagocytosis causes
thrombocytopenia. They usually present as chronic ITP
with anti-HCV antibodies positive in 10-30% of these
patients.52 Moderate thrombocytopenia also develops
following orthotopic liver transplantation in the first
week with gradual resolution in the second week and
requires only supportive care. However persisting or
worsening thrombocytopenia may be due to sepsis,
graft dysfunction, persistent portal hypertension or
hypersplenism.53,54
AST/ platelet ratio (APRI) is a predictor of liver
failure in HBV infection and recurrent HCV after
transplantation. APRI values of ≤0.3 and ≤0.5 rule out
significant fibrosis and cirrhosis, and a value of ≥1.5
is indicative of significant fibrosis. In patients with
NAFLD, APRI values tend to increase with the degree
of fibrosis, suggesting that it could be useful in this
disease. APRI appears to be of no value in patients with
autoimmune hepatitis.55
Platelet count to spleen diameter (PC/SD) ratio less
than 909 is one of several parameters proposed for the
noninvasive prediction of esophageal varices.56
Coagulopathy
Coagulation factors are synthesized in the liver and
can cause abnormal coagulation in liver disease similar
to DIC. A decreasing trend in factor VIII, fibrinogen
and platelets is however more consistent with DIC as
factor VIII is not produced in the liver. It also causes
prolongation of PT, hyperfibrinolysis, dysfibrinogenemia
all increasing the incidence of bleeding in liver
diseases.57 Budd Chiari syndrome is hepatic vein
obstruction at various levels from either thrombosis
or fibrosis. Patients should undergo a hypercoagulable
workup for protein C, protein S deficiencies, factor V
Leiden mutations, lupus anticoagulant, prothombin
gene mutataion and antiphospholipid antibody
syndrome.58,59 Paroxysmal nocturnal hemoglobinuria
should be considered as a possibility when a patient
presents with Budd Chiari syndrome -associated with
pancytopenia.53 Hepatocellular carcinoma is the most
common cause of portal vein thrombosis but non-
malignant PVT incidence is reported in 0.6 to 12%
of patients with cirrhosis.59 It can be asymptomatic
or it may present with worsening of liver disease and
complicates the procedure of liver transplantation.
Decreased portal flow, previous abdominal surgery
and sclerotherapy are identified as causes of portal
vein thrombosis. If underlying inherited disorders are
suspected, a thorough evaluation should be done prior
to liver transplant, as it can increase the risk of post-
operative venous thrombosis.54
Erythrocyte Abnormalities
Anemia in liver diseases is multifactorial. Defective
production of red blood cells could be due to nutritional
deficiencies along with myelosuppression. It could also
be due to acute blood loss in variceal hemorrhage.
Hemolytic anemia occurs as spur cell anemia in NASH
and alcohol liver disease, ribavarin induced hemolysis,
autoimmune hemolytic anemia in autoimmune hepatitis.
Sideroblastic anemia is seen in Wilson’s disease
secondary to treatment with trientene.13,60
Leuckocyte Abnormalities
Leucopenia occurs in cirrhosis secondary to splenic
sequestration, due to circulating hematopoietic
progenitor inhibitory factors, increased apoptosis or
interferon related mechanisms. Decrease in lymphocytes
is probably related to chronic malnutrition.13,60
There is an increased risk of non Hodgkin’s
lymphoma in HCV due to increase monoclonal
proliferation of B cells in HCV.61
Endocrine and the Liver
Endocrine disorders maybe coexistent with underlying
liver diseases. We will highlight only the endocrine
manifestations of liver diseases.
Thyroid Dysfunction in Liver Disease
Various liver diseases can have differing effect on
thyroid hormone metabolism.
Cirrhosis usually produces sick euthyroid
syndrome. As thyroxine- binding globulin is a positive
acute phase reactant, total T4 levels are elevated with
normal freeT4 levels in acute hepatitis. Primary biliary
cirrhosis and autoimmune hepatitis also have associated
autoimmune thyroid diseases. Primary sclerosing
cholangitis is associated with Hashimoto’s thyroiditis,
Grave’s disease and Reidel’s thyroiditis. HCV can
cause thyroid disorders including cancer, independent
of interferon treatment.62
Anti-thyroid antibodies are also seen in 14.7%
of women with chronic HCV infection. Hence it is
essential to screen these patients for thyroid diseases
before treatment.63
Hypothyroidism is also seen with transcatheter
arterial chemoembolization and sorafenib used for
hepatocellular carcinoma treatment. Severe diuretic
resistant ascites can sometimes occur in uncontrolled
hypothyroid cirrhosis. Thyroid hormone replacement
therapy results in regression of the ascites over a few
months. Hypothyroidism should be considered in
patients with portal hypertension when they present
with diuretic resistant ascites, and hormone replacement
therapy often makes them diuretic sensitive.62
Diabetes Mellitus, Lipids and the Liver
The development of diabetes mellitus, metabolic
syndrome and NAFLD is interlinked. HCV infection
is thought to produce diabetes by increasing the insulin
resistance. This defective insulin signaling causes
increased free fatty acid oxidation and triglyceride
accumulation within the liver causing steatosis. This
triggers the inflammatory cascade causing stellate
cell activation and the resultant hepatic fibrosis.
This makes diabetes mellitus and concominant HCV
infection increase the development of hepatocellular
carcinoma.62,64
Screening for diabetes mellitus should be performed
on all HCV patients and the use of hepatotoxic oral
hypoglycemic agents should be used with caution
in these patients. Biguanides, which improve insulin
resistance, and alpha glucosidase inhibitors, which
improve post prandial hypoglycemia, can be used in
this population. that makes them susceptible for central
obesity further aggravating the insulin resistance.65
There is also a 2.3% risk associated hypopituirasim in
patients with NAFLD.13
Adrenal Diseases and the Liver
There is 33 – 66% relative adrenal insufficiency (RAI)
in liver failure and the degree of adrenal dysfunction
correlates with the severity of liver diseases. It is
seen even after orthotopic liver transplantation in the
absence of sepsis. There are improved outcomes with
corticosteroid supplementation.62 However they should
be reserved only for patients with sepsis requiring
vasopressors and at this point recommendations await
further research.
Liver Diseases and Nutrition
The incidence of protein-energy malnutrition in liver
disease is between 30 – 90% and is associated with
adverse survival outcomes. Several studies have shown
that the severe degree of malnutrition was associated
with adverse outcomes even after transplantation.66
Polyunsaturated fatty acid synthesis (PUFA) from
essential fatty acid precursors occur in the liver. PUFA
contributes to the fluidity of the cell membranes. PUFA
deficiency occurs in cirrhosis and is an independent
predicator of mortality of alcoholic cirrhosis. Hepatic
glycogen stores are depleted in chronic liver diseases
and produces severe catabolic state. Branched chain
amino acids (BCAA) has shown to improve energy
metabolism, reduce malnutrition, improve liver function
tests and quality of life in cirrhosis.67 However, as it
may exacerbate glucose intolerance, the use of alpha
glucosidase inhibitors with it is encouraged.
Hence it is important to diagnose these nutritional
deficiencies early to improve mortality. The European
Society for Nutrition and metabolism guidelines state
that subjective global assessment, anthropometry or hand
grip strength are sufficient to identify undernutrition
in this population.68 An intake of 35- 40 kcal/Kg/day
(dry body weight) and 1.2-1.5 g/ kg/ day of protein,
with low sodium content(<2g/day) combined with
supplementation in small frequent meals is generally
recommended in these patients.69
Effects of Liver Diseases
on Other Organ Systems
Advancing liver disease is associated with bone loss
so improved disease progression may improve bone
loss. The pathogenesis is similar to post menopausal
and age related bone loss with estrogen deficiency. The
other factors that either directly or indirectly alter bone
mass such as insulin growth factor-1 (IGF-1) deficiency,
hyperbilirubinemia, alcoholism, excess tissue iron
deposition, subnormal vitamin D levels, vitamin D
receptor genotype, osteprotegerin deficiency, and
immunosuppressive therapy preceding and following
liver transplantation. High turnover osteoporosis
has been described among 20% to 30% of patients
with chronic cholestatic liver disease, primary biliary
cholangitis, and primary sclerosing cholangitis.70
Acclerated osteoporosis has also known to occur in
chronic prednisone use in the setting of autoimmune
hepatitis and post orthotopic liver transplantation
for immunosuppression. Arthritis maybe the first
manifestation of liver disease and it is also the most
common extrahepatic manifestation in primary biliary
cirrhosis, autoimmune hepatitis and hemochromatosis.70
Ophthalmic System
The early recognition of the eye signs can help in
prompt diagnosis of the underlying liver diseases.
Keratoconjunctivitis sicca is particularly common in
50% of patients with primary biliary cirrhosis and 35%
of patients with active hepatitis.
Corneal clouding combined with hepatomegaly is a
feature of several types of storage disorders. The Kayser
Fleischer ring, which is a yellow, red, green or brown
deposit in the peripheral cornea is pathognomic of
Wilson’s disease and resolves completely with treatment.
Lens opacification is a feature of Wilson’s disease,
galactosaemia, Zellwegger’s hepatocerebrorenal
syndrome, neonatal adrenoleukodystrophy, and neonatal
haemolytic jaundice syndrome. Prolonged use of
systemic adrenocorticosteroids for immunosupression
following orthotopic liver transplantation may also be
complicated by cataract formation, opportunistic retinal
and choroidal infections. Mucopolysaccharidoses are
associated with pigmentary retinopathy and two of
the sphingolipidoses manifest macular “cherry red
spot”. Primary biliary cirrhosis may be associated
with treatable night blindness due to malabsorption of
vitamin A. Parinaud’s syndrome is seen in Niemann-
Pick disease, kernicterus and Wilson’s disease. Finally,
there is a rare complication of acquiring hepatitis B
following corneal transplantation, and should be
considered prior to transplant.72
Drug Induced Liver Diseases
Drug-induced liver disease (DILD) occurs in about 25
% of patients of fulminant hepatic failure.73 It accounts
for 2-5% jaundice in hospitalized patients and about
10% of hepatitis in all adult patients.74 The liver is the
primary site of contact of ingested chemicals and the
primary site of biotransformation, thereby making it
especially vulnerable to chemical injury. The factors
that affect vulnerability are related to the conversion
of these ingested agents to a hepatotoxic metabolites.74
It is multifaceted phenomenon and sometimes liver
disease maybe the only clinical manifestation of the
adverse drug effect with or without involvement of
other organs. It may occur either as an idiosyncratic
reaction to the drug (sulfonamides, dapsone, sulindac,
etc.) or a consequence of intrinsic toxicity of the drug
(acetaminophen, inorganic iron, anabolic steroids,
tetracyclines, etc.).75,76 Clinical features most commonly
include fever, eosinophilia and rash. Sometimes also
have lymph node enlargement with atypical circulating
lymphocytes (psuedomononucleosis).76
CONCLUSION
Liver diseases represent an emerging health issue due to
its increasing prevalence and complications worldwide.
It is important for clinicians to be aware of the impact
of liver diseases on the various organ systems to be able
to identify the underlying liver disease early to prevent
long term complications and improve the quality of life
in these patients.
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