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Digestive System Diseases and Disorders 237
Case Studies
■ Stacey Erin is a 32-year-old accountant who has just been diagnosed with peptic ulcer disease. She would
like some information about her disorder and to find out what to expect in the future and how to cope with it.
What would you tell her about peptic ulcer disease? How can she prevent continued problems with her ulcer?
■ Mr. Montgomery was recently diagnosed with colon cancer. He is 67-years-old and was recently widowed.
He has no family members nearby to assist him during the ordeal of coping with the diagnosis, surgical treatment,
and postoperative care. He asks you to explain the treatment and the care that he will need after surgery. He
was told that his cancer has not metastasized, so the surgeon will just do a resection of the colon. What would
you tell him? How can you help Mr. Montgomery with his questions and fear for his future? What resources can
you give him for more information and support?
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12
Liver, Gallbladder,
and Pancreatic
Diseases and
Disorders
Key Terms
Abdominocentesis
(p. 245)
Albumin (p. 245)
Amylase (p. 250)
Ascites (p. 245)
Autodigestion (p. 250)
Caput medusae (p. 244)
Cholecystectomy
(p. 249)
Delirium tremens
(p. 246)
Esophageal varices
(p. 244)
Fulminant (p. 242)
Gynecomastia (p. 246)
Hematemesis (p. 245)
Hepatomegaly (p. 242)
Jaundice (p. 239)
Palmar erythema
(p. 246)
Portal hypertension
(p. 244)
Spider angiomas
(p. 246)
Splenomegaly (p. 244)
Learning Objectives
Upon completion of the chapter, the learner should be able to:
1. Define the terminology common to the liver,
gallbladder, and pancreas, and the disorders of
these organs.
2. Discuss the basic anatomy and physiology of the
liver, gallbladder, and pancreas.
3. Identify the important signs and symptoms
associated with common liver, gallbladder, and
pancreas disorders.
4. Describe the common diagnostics used to
determine the type and cause of liver, gallbladder,
or pancreas disorders.
5. Identify common disorders of the liver,
gallbladder, and pancreas.
6. Describe the typical course and management
of the common liver, gallbladder, and pancreas
disorders.
7. Describe the effects of aging on the liver,
gallbladder, and pancreas and the common
disorders associated with aging of the organs.
Overview
T
he liver, gallbladder, and pancreas are the accessory organs of digestion. Although these organs are not
considered part of the digestive system, they have important roles in the digestive process as well as in
many other functions in the body. Disorders of the liver, gallbladder, or pancreas can cause serious digestive
problems and many other systemic disorders. ■
239
Anatomy and Physiology
The liver is the largest solid organ of the body, taking
second place only to the skin as the largest organ overall
(Figure 12-1). The liver has many functions, most of
which are related to its chemical actions. It plays a role
in digestion, absorption, metabolism, blood clotting,
the manufacture of important chemicals, and storage
of nutrients. The liver is composed of two lobes, weighs
about 3.5 pounds, and lies in the upper-right quadrant
of the abdomen. Some of the most important functions
of the liver include:
■ Production and secretion of bile used for fat digestion.
■ Production of cholesterol.
■ Oxidation of fatty acids and glycerol used for body
energy.
■ Metabolism of carbohydrates, fats, and protein.
■ Conversion of glucose to glycogen for storage and the
reverse process for energy.
■ Synthesis of amino acids.
■ Detoxification of many drugs and other toxins.
■ Storage of vitamins and other minerals.
■ Production of fibrinogen and prothrombin for
blood clotting.
The liver receives blood from the portal system
through the portal vein and the hepatic artery. About
1,450 ml of blood flows through the liver every minute.
The blood returns to the circulatory system through the
hepatic vein to the inferior vena cava.
Bile to emulsify, or break down, lipids in the intes
tine is continually produced in the liver and conducted
through the hepatic duct to the duodenum. When bile
is not needed in the digestive process, excess bile is
stored in the gallbladder until needed by the intestine
in the digestive process.
Consider This...
If the liver were to totally stop working,
without medical intervention, the individual
would die within 24 hours.
Figure 12-1 The liver, gallbladder, and pancreas.
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Liver, Gallbladder, and Pancreatic Diseases and Disorders 241
The gallbladder is a small, pear-shaped organ lying
just under the liver (see Figure 12-1). Bile travels from
the gallbladder to the duodenum via the cystic duct and
the common bile duct.
The pancreas lies in the abdomen behind the
stomach between the duodenum and the spleen (see
Figure 12-1); it is both an endocrine gland (the islet
cells secrete hormones) and an exocrine gland, pro
ducing and secreting most of the digestive enzymes.
The pancreas secretes intestinal juices consisting of
chymotrypsin and trypsin, which break down proteins;
amylase, which breaks down starch; and lipase, which
breaks down fats. The pancreatic juices exit the gland
by way of the pancreatic duct to the duodenum.
Common Signs and Symptoms
Jaundice (JAWN-dis, a yellowish discoloration of the
skin) is an obvious symptom of liver disease and can be
secondary to gallbladder disease as well. If a bile duct
is blocked, for instance, the bile backs up into the liver
and leads to jaundice (Figure 12-7)
Jaundice is caused by high levels of bilirubin in the
blood. Bilirubin is a by-product of the breakdown of
heme, the main component of hemoglobin in red blood
cells. The liver filters bilirubin out of the blood and
excretes it in bile. If the liver is unable to filter bilirubin
and excrete it, hyperbilirubinemia (hyper = too much,
bilirubin, emia = blood), or excessive bilirubin in the
blood, occurs. This excess leaks into the tissues, and
the individual’s skin, mucosa, and sclera (white part of
the eye) become yellowish in color.
Bilirubin can be broken down in the skin by expo
sure to sunlight or direct lighting, which explains the
use of bili lights to clear bilirubin in a jaundiced new
born infant. Excessive bilirubin is also filtered out of the
blood by the kidneys, causing dark brown urine.
Pain is a common symptom of gallbladder disease,
pancreatitis, and end-stage pancreatic cancer. With gall
bladder disease, right-sided abdominal pain commonly
occurs following a meal containing fat. Acute abdomi
nal pain occurs with pancreatitis and pancreatic cancer.
Diagnostic Tests
Liver function tests are blood tests to measure levels of
bilirubin, albumin (blood protein), and alkaline phos
phatase (enzyme). Impaired liver function will lead to
elevated bilirubin and alkaline phosphatase levels and
low albumin levels.
Ultrasound is used to evaluate the liver, gallblad
der, and pancreas for size, shape, and position. X-ray
examinations of the gallbladder and the vessels of
the gallbladder (cholecystogram and cholangiogram,
respectively) use radiopaque dye to show the presence
of gallstones, tumors, and function of the gallbladder.
Ultrasonography is used more often than the previously
mentioned radiologic examinations.
A hepatobiliary iminodiacetic acid (HIDA) scan
also called cholescintigraphy is a test that can be done
to view the gallbladder, bile ducts, liver, and small intes
tine. In this test a radioactive tracer is injected into the
individual and a special camera tracks the material as it
is taken up by the gallbladder.
Computer axial tomography (CAT or CT) scans
can be performed to visualize the liver, gallbladder, and
pancreas. Visualization of these organs aids in the diag
nosis of hepatic and pancreatic cancer. A liver biopsy
can be performed by needle biopsy or during laparo
scopic surgery. Biopsy is the most reliable test for deter
mination of chronic hepatitis, cirrhosis, and cancer.
An endoscopic retrograde cholangiopancreatog
raphy (ERCP) is a test using dye injected into a tube
inserted through the mouth into the stomach and small
intestine. An X-ray is then done to visualize the gall
bladder, liver, and pancreas.
Blood tests to measure pancreatic function com
monly include serum amylase and lipase. Amylase and
lipase are digestive enzymes produced by the pancreas
that break down carbohydrates and fats, respectively.
Common Diseases of the Accessory
Organs of Digestion
Diseases of the accessory organs of digestion can seri
ously affect the digestion and metabolism of nutrients.
Symptoms of these disorders reflect an interference
with the particular organ’s function. Over 30 million
individuals—1 in 10—in the United States have been
diagnosed with liver disease. Obesity is quickly becom
ing the leading cause of liver disease (American Liver
Foundation, 2017).
Liver Diseases
Liver diseases can range from mild inflammation to
those that destroy the liver and result in liver failure.
Any disease of the liver can have serious consequences
by interfering with the many functions of the liver.
Hepatitis
■ Description. Hepatitis is inflammation of the liver
that can lead to abnormal function and other diseases
or conditions.
242 Chapter 12
Healthy Highlight
Keeping Your
Liver Healthy
H ere are some tips for maintaining a healthy liver:
■ Eat a healthy diet and get plenty of exercise. This reduces the chance for developing
non-alcoholic fatty liver disease (NAFLD).
■ Reduce alcohol intake or drink alcohol in moderation. The guidelines state women
should drink no more than one drink per day and men no more than two.
■ Avoid the risk for developing hepatitis. Use condoms when engaging in sexual activ
ities, do not share needles, toothbrushes, or razors, and get the vaccination for type A
and B. Get tested for hepatitis C because it does not show early symptoms.
■ Be careful when using any cleaning products; avoid inhaling the fumes. The toxins
can harm the liver.
■ Be careful if using dietary supplements. Some supplements are harmful to the liver.
■ Drink a moderate amount of coffee daily. Research is demonstrating the benefit of
drinking three to four cups of coffee daily.
■ Be careful when taking over-the-counter medications. Acetaminophen can cause liver
damage if taken in large quantities or mixed with alcohol. Other prescription medi
cations, such as cholesterol-lowering medications, may also have adverse effects on
the liver. Be sure to talk to your health care provider about this. Routine lab testing
might be indicated.
Pharmacology
Highlight
Common Drugs for Liver, Gallbladder, and Pancreatic Disorders
Category Examples of Medications
Alcohol Abuse Treatment
Acamprosate, or naltrexone
Antineoplastics
Drugs used to treat cancer
Alkylating agents
Antimetabolites
Chlorambucil, cyclophosphamide, or lomustine
5-Fluorouracil, mercaptopurine, or methotrexate
Antitumor antibiotics Mitomycin or streptozocin
Hormones/antihormones Androgens, estrogens, flutamide, or tamoxifen
Kinase inhibitor Cabozantinib
Other substances Bevacizumab, carboplatin, cisplatin, etoposide,
gemcitabine, irinotecan liposome, l-asparaginase,
leucovorin, nivolumab, paclitaxel, pemigatinib,
oxaliplatin, or vincristine
Antivirals
Drugs used to stop the action
of the virus
Acyclovir, cidofovir, or imiquimod, interferon
alfa-2b, ribavirin, simeprevir, or sofosbuvir
Cholesterol Medications
Drugs used to lower levels of
cholesterol or increase levels
of beneficial cholesterol
Atorvastatin, cholestyramine, colestipol, fenofibrate,
gemfibrozil, pravastatin, or simvastatin,
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Liver, Gallbladder, and Pancreatic Diseases and Disorders 243
Common Drugs for Immune Disorders (continued)
Category Examples of Medications
Immune System Booster
Interferon
Vitamins/Minerals
Supplements used to
support or replace low
levels
Calcium, chromium, folate, iodine, iron, magnesium,
niacin, selenium, vitamins A, B6, B
12
, C, D, E, K, or
zinc
These may be prescribed individually or in
combinations.
■ Etiology. Hepatitis might be caused by the chemical
action of drugs or toxic substances. Chronic alcoholism
often leads to hepatitis prior to the functional changes
seen with cirrhosis, but the most common cause of hep
atitis is a group of viruses. This form of hepatitis is often
called viral hepatitis and is the form most commonly
thought of when one considers hepatitis.
Viral hepatitis is the most prevalent liver disease in
the world and is often asymptomatic. When symptoms
do occur, they can be so vague that the disease is often
misdiagnosed. Viral hepatitis occurs in five basic types.
A different virus causes each type. The types of hepatitis
are A, B, C, D, and E.
Hepatitis A (HAV)
The most benign or harmless form of hepatitis. Recov
ery without treatment is common. This virus is spread
by fecal-oral route and commonly affects children and
young adults, especially in areas where there is poor
sanitation and overcrowding. Symptoms are usually
very vague and similar to flu, often leading to misdi
agnosis. The virus is shed in the feces, and the affected
individual does not become a carrier of the disease.
HAV never leads to chronic hepatitis or cirrhosis. A
vaccine is available and is recommended for those trav
eling or living in a high-risk area.
Hepatitis B (HBV)
A serious form of hepatitis formerly called serum hepa
titis. It was once thought that HBV was spread only by
contact with blood, as occurs with blood transfusions
and contaminated needles. However, it is now known
that saliva, urine, feces, and semen can spread the virus,
which also qualifies it as a sexually transmitted disease.
Among adults HBV is most commonly spread
through sexual contact. HBV is approximately 100 times
more infectious than human immunodeficiency virus
(HIV), the virus that causes acquired immunodefi
ciency syndrome (AIDS) (Hepatitis B Foundation,
2017). HBV also can spread transplacentally (across the
placenta from mother to unborn infant).
This virus is a major health problem, with over
240 million individuals infected worldwide. Another
major concern is the fact that individuals can
unknowingly become carriers of the virus and carry
it for years or even a lifetime. Carriers are not only
a threat to others, but also are at high risk for devel
oping chronic hepatitis and cirrhosis. Approximately
20,000 new infections occur every year in the United
States (CDC, 2018).
The good news is that the number of new cases of
HBV has decreased approximately 82% over the past
20 years primarily due to childhood vaccinations. Those
at high risk for HBV are individuals with substance use
disorders, gay men and women, blood recipients, and
health care professionals. The best prevention is to get
vaccinated. The HBV vaccine is approximately 90%
effective in prevention of the disease.
Hepatitis C (HCV)
Similar to HBV because it also is spread by blood or
sexual contact but differs from HBV in that it attacks
the RNA of a cell, whereas HBV attacks the DNA. After
HCV was distinguished from HBV, it was found to be
the cause of most cases of hepatitis following blood
transfusion (post-transfusion hepatitis). Today, with
improved blood screening techniques, the most com
mon cause of HCV is related to drug use.
HCV is more likely to become chronic hepatitis
than HBV, with approximately 75% of those affected
with HCV developing chronic hepatitis and cirrhosis.
HCV progresses very slowly and may take 10 to 40 years
before serious liver damage is discovered. There is no
vaccine available for HCV.
244 Chapter 12
Dietary
Supplements
for Hepatitis C
Complementary and Alternative Therapy
R
esearch on the benefit of taking supplements for treating hepatitis C has not demon
strated its effectiveness for relieving symptoms or curing the chronic condition of
the liver. The National Center for Complementary and Integrative Health (NCCIH),
a division of the National Institutes of Health (NIH), has reported that the most com
mon dietary supplements used by individuals with hepatitis C, such as colloidal silver,
silymarin, licorice root, and lactoferrin, have not been shown to have any positive or
curative effects. There are some studies that have shown dietary supplements have some
benefit, but none have been shown to be effective for hepatitis C at this time. In fact,
some may even be dangerous and cause irreversible untoward side effects. One study
showed silymarin to be no more beneficial than a placebo. Consumers should be careful
in their choices of dietary supplements. Some supplements also interact with prescrip
tion medications which could also be harmful.
Source: National Center for Complementary and Integrative Health (2019)
Hepatitis D (HDV)
Also called the delta virus. It requires the presence of
HBV to replicate. Infection with both HBV and HDV
can cause more prominent symptoms and a greater risk
of developing chronic and fulminant (FULL-ma-nant;
to occur suddenly and with great intensity) hepatitis.
The best prevention is to vaccinate against HBV.
Hepatitis E (HEV)
Similar to HAV in that it is spread through the fecal-
oral route. It is commonly due to water contamination.
Chronic hepatitis does not develop with HEV, but this
virus can be fatal in pregnant women.
■ Symptoms. Jaundice is often the first symptom that
signals a liver problem, although not all individuals
become yellow. Interestingly, those who become more
jaundiced are more likely to have a good recovery than
those who are less jaundiced. Individuals with mild jaun
dice are more likely to develop chronic hepatitis. Other
symptoms include malaise, anorexia, myalgia (myo =
muscle, algia = pain), fever, and abdominal pain. Phys
ical examination might reveal hepatomegaly (HEP-ah-
toh-MEG-ah-lee; hepato = liver, megaly = enlargement).
Dark-colored urine and clay- or light-colored stools are
related to the inability of the liver to form normal bile.
■ Diagnosis. A blood test showing hepatitis virus anti
bodies is adequate for diagnosis.
■ Treatment. Treatment for HAV in most cases is symp
tomatic. Antivirals are also used, especially for HBV and
HCV. General treatment includes adequate rest and
good nutrition, which are essential for all types.
The most serious complications with hepatitis are
development of chronic hepatitis and fulminant hep
atitis. Chronic hepatitis develops in one out of four
cases and often leads to cirrhosis of the liver. Fulmi
nant hepatitis is acute liver failure that causes extensive
necrosis of liver tissue. Symptoms include a high fever,
hemorrhages from the skin and mucous membranes,
confusion, and stupor. Acute liver failure is a medical
emergency. Treatment may reverse the failure but often
coma develops and leads to death.
■ Prevention. Prevention of hepatitis involves good
hygiene and special care when handling needles and
body secretions.
Other activities that aid in prevention include:
■ Avoiding excessive alcohol consumption.
■ Avoiding use of illegal drugs.
■ Avoiding unprotected sex, especially with multiple
partners.
■ Receiving the hepatitis vaccines, especially for those
in a high-risk group.
Other Diseases of the Liver
Cirrhosis
■ Description. Cirrhosis (sir-ROH-sis) of the liver is a
chronic, irreversible, degenerative disease also known
as end-stage liver disease. It is characterized by the
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Liver, Gallbladder, and Pancreatic Diseases and Disorders 245
Figure 12-2 Hobnail liver.
replacement of normal liver cells with nonfunctioning,
fibrous scar tissue, giving the surface of the liver a nodular
appearance known as hobnail liver (Figure 12-2). This
change in structure and function of the liver cells leads
to impaired blood flow and altered function of the liver.
■ Etiology. The most common cause of cirrhosis is
chronic alcoholism. Cirrhosis is more common in men
than in women. It also can be idiopathic or the end
result of other diseases such as chronic hepatitis and
congestive heart failure. The development of the dis
ease often takes years. Symptoms usually do not appear
until serious structural and functional changes in the
liver tissue have occurred. If symptoms occur, they are
usually mild and nonspecific and might include loss of
appetite, nausea, indigestion, weakness, and weight loss.
As the disease progresses, the abnormal scar tissue
alters blood flow through the liver and leads to a variety
of complications such as blood backing up in the hepatic
portal vein. The relationship of the liver, the hepatic por
tal system, and the digestive system is as follows:
■ The purpose of the hepatic portal system is to carry
venous blood from the spleen and digestive organs
(esophagus, stomach, and intestines) to the liver
(Figure 12-3). The liver plays a major role in the
digestive system by detoxifying and metabolizing
_______Inferior vena cava
Hepatic veins
Liver
Stomach
Spleen
Splenic vein
Pancreas
Hepatic portal vein '
Superior mesenteric vein
Inferior
mesenteric vein
Descending
colon
Ascending
colon
Small
intestine
Figure 12-3 Hepatic portal system.
246 Chapter 12
nutrients before releasing them into the systemic
blood in the inferior vena cava. For example, if an
individual consumes a meal with an alcoholic bever
age, these nutrients are absorbed into venous blood
in the small intestine and transported to the liver to
be filtered, detoxified, and stored. The liver’s respon
sibility, in part, is to keep blood glucose levels from
soaring when an individual eats a high-carbohydrate
meal. Nutrients are filtered, metabolized, stored, and
released as needed into the systemic circulation by the
liver. Toxins such as alcohol are detoxified. If alcohol
consumption is too great or outpaces the liver’s ability
to detoxify the blood, the blood alcohol level will rise.
■ If the liver is obstructed for any reason, blood will
back up in this portal system. As blood backs up,
pressure increases in the portal vein and is called
portal hypertension.
■ Symptoms. Complications of severe cirrhosis can
include:
1. Varicosities Portal hypertension causes varicosi
ties (varicose veins) of the veins of the digestive
system organs. Varicosities are commonly
located in the esophagus (esophageal varices)
(Figure 12-4). Esophageal varices (VAIR-ah-
SEEZ) are prone to rupture, leading to massive
hemorrhage, shock, and death. Other sites of
varicosities include the rectum (hemorrhoids)
and anterior abdominal wall. Varicosities across
the front of the abdomen are often quite tortuous
and unsightly, a condition called caput medusae
(Medusa’s head) because the physician who named
the condition was reminded of Medusa’s head
when observing the varicosities (Figure 12-5).
Medusa, in Greek mythology, was a woman who
had snakes on her head in place of hair.
2. Splenomegaly Portal hypertension also causes
increased pressure on the organs that are
connected to or drained by the portal system.
Often, this passive congestion in the spleen
leads to splenomegaly (SPLEE-no-MEG-ah-
lee; spleno = spleen, megaly = enlarged). The
normal spleen weighs approximately 150 g
(1/3 pound) and is 11 cm (4 inches) long.
Courtesy of Mark L. Kuss Courtesy of Mark L. Kuss
Figure 12-4 (A) Esophageal varices and splenomegaly. (B) Esophageal varices — internal view. (C) Splenomegaly.
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