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All definitions are provided by members of the
C.L.A.S.S.
Scientific Advisory Board.
acholic
Without bile pigment in the stools. Causes stools to be pale in color.
Actigall
Actigall (Ursodiol) is a drug used to treat some biliary disorders.
The drug itself is a bile acid and after being absorbed it is excreted
into bile and can result in the dissolution of certain types of gall
stones that are composed predominantly of cholesterol. It is also
recommended to treat primary biliary cirrhosis and appears to slow the
progression of this disease. It is also used in some cases to treat
biliary atresia, but there is currently insufficient evidence that it
is effective in these patients.
Alagille syndrome
alcoholic
The term alcoholic is generally defined as someone who is addicted to
alcohol. Addiction in turn is defined as a maladaptive pattern of
drinking that leads to significant personal problems as defined by 3
or more of the following in the same 12 month period:
- Drinking larger amounts or over longer period than intended.
- Persistent desire or unsuccessful efforts to cut down or control
drinking.
- Drinking that interferes with family, friends, or job.
- Continued drinking despite negative consequences such as
divorce, lost job, DWI conviction.
- Tolerance, meaning that over time it takes more alcohol to get
drunk than it used to.
- Withdrawal, meaning that the person has unpleasant symptoms if
they stop drinking.
alpha 1-antitrypsin deficiency
ammonia intoxication
Urea and ammonia are two by-products of the metabolism (usage and
break-down) of proteins. They are handled and eliminated via very
sophisticated mechanisms within liver cells. In the case of liver
damage, be it acute or chronic (long-lasting with slow progress), the
ammonia accumulates to become toxic, particularly to the brain which
swells in its presence.
anicteric
A technical term meaning jaundice-free.
ascites
Ascites is fluid within the abdomen. It can occur for a variety of
reasons including liver disease, kidney disease, heart failure, and
malnutrition. The starving children in pictures of famine stricken
areas have large swollen abdomens due to ascites that is from
malnutrition. Their diet contains too little protein which leads to
abnormally low amounts of a protein in the blood called “albumin.”
Albumin normally keeps fluid in the blood stream through a physical
force called “colloid osmotic pressure.” When the albumin level is
too low, either because it is lost in the urine or because of
malnutrition, the colloid osmotic pressure falls. If the colloid
osmotic pressure is below venous pressure, fluid leaks out of the
blood stream and ascites results.
Some people with kidney failure develop leaky kidneys that spill
albumin into the urine, leading to low blood levels of albumin. People
with heart failure develop ascites because pressure builds up the
veins that lead to the heart. If this increased venous pressure
exceeds colloid osmotic pressure, ascites results. People with liver
failure develop ascites for two reasons: Since the liver makes albumin
out of dietary protein, liver failure patients may have a low amount
in their blood stream even if they have adequate nutrition because of
the liver’s decreased ability to make new protein. Also, liver
failure patients develop portal hypertension which can tend to elevate
the venous pressure above colloid osmotic pressure.
avascular necrosis of the
joint (also called “aseptic necrosis”)
A condition where the bone dies for unknown reasons. It is most common
in the femur (thigh bone), but it can also happen in the knees and
arms. The usual symptom is pain and the diagnosis is made by x-rays.
Symptoms can appear before the diagnosis can be made by x-ray.
Sometimes there are little or no symptoms. It is more common after
kidney transplantation compared to liver and heart transplantation.
Treatment may include adjustment of prednisone dosage, pain
management, and sometimes joint replacement.
biliary atresia
A congenital (developmental) malformation of the biliary tract where
the biliary ductules outside the liver do not form to collect the bile
from the liver cells to bring it out into the intestine. According to
the degree or severity of the defect, there may be different types
which usually involve the gallbladder.
biliary cirrhosis
see primary biliary cirrhosis
and secondary cirrhosis
biliary stasis
bilirubin
Bilirubin is a chemical breakdown product of hemoglobin. Hemoglobin is
a substance in red blood cells that grabs onto oxygen in the lungs and
carries it to the tissues in the body where it releases it. When red
blood cells wear out they are trapped in the spleen and destroyed,
releasing bilirubin into the blood. This type of bilirubin is called
unconjugated. The liver takes the bilirubin out of the blood and
conjugates it by attaching a portion of another molecule to the
bilirubin molecule. Conjugated bilirubin can then be excreted in bile
by the liver. The bile then goes through the bile duct into the
intestine. Eventually the bile winds up exiting the body in feces.
Bile gives the feces its brown color. If the liver is not producing
bile or if the bile duct is blocked, the color of feces is tan.
biopsy
A biopsy is whenever tissue is removed from an organ or tissue in
order to tell something about the organ or tissue. There are many
types of biopsies:
- A fine needle biopsy (sometimes called a “fine needle
aspiration”) involves inserting a long, very thin, needle and
aspirating cells for analysis.
- A core needle biopsy involves placing a specially designed
needle into the organ in order to draw out a tiny cylinder of
tissue for analysis.
- A wedge biopsy involves an actual operation: A sliver of the
organ is taken out with a scalpel for analysis.
Fine needle biopsies are usually used to determine whether a lump
or “mass” is a cancer or something else. Since only a few cells
are provided with a fine needle biopsy, it is not possible to be
certain that a lump is not cancer, but it may be possible to prove the
lump is cancer, or that it is something else.
Core needle biopsies are used when it is necessary to see the cells
and how the cells are arranged, in order to make a diagnosis. Liver
and kidney biopsies are usually core biopsies. In order to tell the
cause of a patient’s kidney disease, or whether a liver transplant
is being rejected, it is often necessary to biopsy the organ in
question.
Open biopsies, or wedge biopsies, are usually done when needle
biopsies are unsafe because of the risk of bleeding. Since the needles
are small, any bleeding will almost always stop on its own after a
needle biopsy. However, in a patient who has an abnormal tendency to
bleed, a needle biopsy may not be safe; therefore, these patients need
open biopsies. During an open biopsy the surgeon can use
electrocautery and sutures to stop bleeding after the biopsy is taken.
CellCept®
An immunosuppressive drug used with other immunosuppressants to
prevent the rejection of the transplanted organ. Also known by its
chemical name, myophenolate mofetil.
chimerism
A term meaning that one organism is made up of cells with more than
one genetic background. All transplant patients are chimera's since
they have cells from another person living within them.
cholangitis
Cholangitis is a bacterial infection in the bile duct. The symptoms
and signs can include fever, elevation in bilirubin level, jaundice,
chills, confusion, low blood pressure, elevations in liver enzymes,
especially alkaline phosphatase. In general, something must be
abnormal for cholangitis to occur: either there is some sort of
obstruction to bile flow, such as a gall stone lodged in the duct, or
scarring of the duct due to an inflammatory disease (e.g. sclerosing
cholangitis), or some other sort of blockage, or the biliary anatomy
is abnormal due to previous surgery. Patients that have abnormal
biliary anatomy because they have had a porto-enterostomy (Kasai) or
an operation that includes a roux-en-y reconstruction of the bile duct
can have cholangitis for no good reason. However, in patients that
have had a Kasai operation, recurrent cholangitis is considered to be
a sign of impending liver failure and is sometimes used as an
indication for liver transplantation. The treatment is antibiotics,
plus relief of the obstruction, if one exists.
cholestyramine
Medication categorized as a resin which acts like a “sticky”
substance that binds many other chemicals including metals, vitamins,
and bile acids. For this last reason it is frequently used to treat
itching in patients with liver disease.
cholestasis
Cholestasis is a non-specific term for a build up of bile in the
liver. This can happen for many different reasons. At times the
cholestasis is related to a transient injury of the liver and it will
often go away on its own. It can also be caused by drugs, in which
case it may go away if the drug is discontinued. Cholestasis can also
be the result of liver diseases such as sclerosing cholangitis,
biliary atresia, primary biliary cirrhosis, and others.
cirrhosis
Cirrhosis is a process in the liver that is characterized on biopsy as
having scarring and nodule formation. It is thought to occur following
the death of many, many liver cells. A simplified explanation is that
something hurts the cells of the liver, which then die, leaving a
scarred liver. A liver with cirrhosis may be small and shrunken, as in
the case of cirrhosis due to hepatitis or excessive alcohol, or it may
be very much enlarged, as in the case of primary biliary cirrhosis and
biliary atresia. In all cases it is nodular and firmer than it should
be. Normal liver is very soft and spongy. A liver with cirrhosis is
very firm and hard. The exact cause of cirrhosis is not known.
clotting studies
Clotting studies are laboratory measurements of the body’s ability
to clot. Examples include prothrombin time (PT), partial
thromboplastin time (PTT), platelet count, and bleeding time. Each
measurement looks at particular factors that are necessary in order
for one to have a normal ability to clot.
congenital
Describes a condition present from birth. Congenital malformations
include all disorders present from birth whether they are inherited or
caused by environmental factors.
costal margin
Refers to the lower edge of the rib cage.
cyclosporine
A drug, derived from a fungus, that inhibits the body’s immune
responses. It is a standard drug for patients with organ transplants
and is also used in some autoimmune diseases. Most organ recipients
are kept on cyclosporine, or a similar drug called “tacrolimus,”
for as long as they have a functioning organ transplant.
decompensation
Decompensation means simply that a process that was formally stable
has become unstable leading to failure. For example, a person who
develops lung disease will begin to breath deeper and more quickly.
They then are said to have “compensated” lung disease. However, if
the lung disease gets bad enough, the person will not be able to
breath fast enough and deeply enough without tiring. When this
happens, the person is said to have “decompensated” lung disease.
diuretic
A drug that causes the body to excrete sodium (salt). These drugs work
by making the kidneys produce more urine, hence more salt is lost.
esophageal varices
Esophageal varices are enlarged veins in the esophagus. The esophagus
is the muscular tube that connects the back of your throat to your
stomach. It runs down the chest between the two lungs, behind the
heart. Varices usually develop because of a build up in pressure in
the veins leading to the liver. This problem, called “portal
hypertension,” occurs in patients with liver disease. The increased
pressure in the veins leading to the liver causes blood to try to find
a way back to the heart other than through the liver. There are
several channels that allow blood to do this, but ordinarily only a
tiny amount of blood is going through these channels. When portal
hypertension occurs, these channels, called “collateral
circulation,” become swollen with blood. Esophageal varices and
hemorrhoids are examples of these collaterals. Esophageal varices can
burst spontaneously and lead to massive bleeding which may be apparent
because the patient vomits blood or begins to have bloody bowel
movements.
fatty liver
This is just what it sounds like: fat in the liver. It tends to occur
in people that are overweight. Another term used is steatosis.
Non-alcoholic steatohepatitis (NASH) is a problem that has been
recently identified and written about in medical literature. It seems
to be an advanced form of fatty liver. The significance and prognosis
of NASH has not been defined well yet. Fatty liver will often go away
with dietary modifications. Livers that are fatty may function
normally, but for reasons that are unclear they make very poor
transplant grafts. Fatty livers often do not work following the period
of cold time associated with a transplant, therefore if a liver is
extremely fatty it is not used for transplantation.
failure to thrive
fibrosis
Refers to the presence of scar tissue or collagen fibers in any
tissue. In the liver, fibrosis or scarring of the liver damages the
architecture and thus the functionality of the organ. Fibrosis,
combined with the liver’s ability to regenerate, causes cirrhosis
(regeneration within the scar tissue).
gallbladder
graft
A tissue or organ that is removed and placed somewhere else. If the
graft is from one person to themselves (for example, a hair transplant
for bald men where their own hair is moved from the back of the head
to the top), it is called an “autograft.” If the graft is between
identical twins, it is called an “isograft” (this kind of graft is
not rejected). If the graft is between members of the same species
(for example, between father and son), the graft is called an “allograft.”
If the graft is between different species (for example, a heart valve
graft from a pig to a human), it is called a “xenograft”
(pronounced ZEE-no-graft).
hepatomegaly
Enlargement of the liver to such an extent that it can be felt below
the ribs.
histology
The study of the structure of living tissue. For example, the
"histology" of a tumor is determined by a biopsy of the
tumor which is looked at under a microscope.
hyperlipidemia
Hyperlipidemia means that there are excess levels of fats in the
blood. These fats can be triglycerides, or cholesterol. Hyperlipidemia
is often associated with increased risk of heart disease and strokes.
There are genetic disorders that predispose to hyperlipidemia.
Hyperlipidemia can also be caused by some medications including
prednisone and others.
icteric
A technical term for jaundice.
immune system
The cells and proteins in the body that respond to infection and fight
it off.
immunosuppressant
Anything that inhibits or weakens the immune system.
Immunosuppressants can be drugs like prednisone and cyclosporine or
can be diseases like cancer and AIDS.
Imuran
A drug that suppresses the immune system by inhibiting cells that
divide rapidly.
infection
Anything that invades the body and reproduces. Infections can be
bacteria, protozoa, fungi, or viruses. Bacteria and fungi are one
celled creatures that cause many infections including strep throat,
bladder infections, and some lung infections. Fungi cause
“athlete’s foot” and thrush, an infection in the mouth. Protozoa
are small organisms with many cells that can cause infections in the
guts or in the lungs. Most healthy people do not get protozoal
infections, but people with suppressed immune systems can. Viruses are
not really organisms; they are tiny particles that can live only
inside another cell. They reproduce by taking over a cell and causing
that cell to make more virus particles, rather than doing what the
cell is supposed to do. Viruses cause most colds and flu cases.
intravenous
Within the blood stream.
jaundice
Yellowish discoloration of all the tissues in the body, including the
white of the eyes and the skin, that occurs when the blood contains
abnormal amounts of the pigment bilirubin, which is normally excreted
in the bile.
Kasai procedure
malabsorption
Malabsorption is a problem with absorbing nutrients from the
intestines. Malabsorption can happen for a variety of reasons
including diseases of the bowels that impair absorption. Another
example is pernicious anemia, a disease of the stomach that results in
impairment of vitamin B12 absorption. Some vitamins (A, D, E, and K)
require bile for absorption. In patients with liver diseases that lead
to insufficient bile production, absorption of these vitamins is often
impaired.
metabolism
The way in which chemicals in the body are changed by the body.
Poisons and toxins are disposed of by metabolism. Nutrients are used
to build cells by metabolism.
milk thistle
Milk thistle is an herb that is said to be good for people with liver
problems. It is thought that the active component in the herb is a
substance named silymarin. Silymarin has been studied scientifically
many times and to date no evidence has appeared that it has an
important beneficial effect.
ophthalmologist
A doctor that specializes in eyes.
OTK3
OKT3 is a monoclonal antibody. Antibodies are proteins that are made
by the immune system to fight infections. Antibodies usually attach to
the surface of cells in the body and can cause the cell to die by a
variety of mechanisms. Monoclonal antibodies are antibodies that are
all exactly the same. They are made by taking the cell from an animal
that makes antibodies and fusing that cell with a cancer cell from the
same species of animal. This results in a cell that will live forever
and make lots and lots of the same antibody. Most monoclonal
antibodies are made in mice.
The OKT3 monoclonal antibody binds to a protein on the surface of T
cells called CD3. When this happens, the cell doesn't die, but it
"activates" as if it had encountered a germ to fight
against. The cell then secretes a number of chemicals into the blood
and becomes dormant for a period of days. These chemicals tend to make
the person receiving the antibody sick as if they have a bad
infection: fever, headache, joint aches, nausea, diarrhea, muscle
pain. Generally OKT3 is given either at the time of a transplant to
prevent rejection from occurring, or to patients that have received a
transplant and later developed rejection. OKT3 is very effective in
both settings, but the side effects are very bothersome to the patient
for the first 3-4 days.
pathology
The study of disease. Pathologists tend not to work with living
patients, but with specimens of tissue or blood which are analyzed in
order to provide information that will benefit the patient.
Pathologists oversee the labs where blood tests are run and look at
specimens from biopsies under microscopes to diagnose diseases like
cancer. Pathologists also do autopsies on cadavers to find the cause
of death.
phenobarbital
Medication derived from a barbiturate which acts in the nerve cells of
the nervous system. It is broken down and metabolized in the liver
creating an increase in several enzymes that handle other medications
or chemical substances. Even though it’s a sedative and anti-seizure
medication, it was used in the past as a way to try to enhance the
excretion of bile. Because of those ‘metabolic’ characteristics,
it also alters the way the liver handles many other medications.
prophylactic antibiotics
Antibiotics prescribed or used to prevent certain specific infections.
portal hypertension
Portal hypertension is high pressure in the portal system. The portal
system is made up of the veins that collect blood from the stomach,
bowels, pancreas, and spleen. These veins come together and make up
the portal vein which leads to the liver. When the liver is diseased,
the blood cannot get through the liver very easily, so the pressure in
the portal vein increases. This causes a number of problems including
an enlarged spleen (splenomegaly), the
collection of fluid in the abdomen (ascites),
and a tendency to bleed from enlarged veins in the stomach and
esophagus (varices).
primary biliary cirrhosis
A disease of the liver that leads to liver failure. It is more common
in women than men and is thought to have an autoimmune cause, meaning
that the body's own immune system damages the liver.
pruritus
A technical term for itching.
PTLD
PTLD stands for post transplant lymphoproliferative disease. This is a
problem that occurs in transplant patients and is believed to be
caused by an interaction between immunosuppression medications and a
chronic viral infection called EBV (Epstein Barr Virus). PTLD occurs
in a small percentage of transplanted patients and can progress to
lymphoma, a cancer of the blood cells. PTLD can sometimes be treated
by decreasing or stopping the immunosuppression medications.
rejection
When the body fights against a tissue or organ as if it were infected
or damaged. This process usually results in damage to that organ or
tissue.
rickets
A disease of weak bones caused by not getting enough vitamin D.
Patients with liver disease can get rickets because their liver may
not make enough bile, which is necessary to absorb vitamin D. Patients
with kidney disease can get rickets because vitamin D is activated in
the kidneys.
secondary biliary cirrhosis
Liver disease due to chronic obstruction of the bile duct. The bile
duct can be obstructed by many different things including: Gall stones
that migrate out of the gall bladder and get lodged in the bile duct.
A tumor of the bile duct or a nearby structure like the duodenum
(first portion of the small intestine). Inflammation (swelling) of the
pancreas.
spleen
Organ that belongs to the Reticulo-endothelial, Hematological and
Immune Systems. Localized in the abdomen, opposite the liver, under
the rib cage on the left side of the abdomen. The spleen removes old
or used and deformed blood cells including red cells, white cells, and
platelets and generates a type of white cells, called
“lymphocytes” which are responsible for the production of
antibodies. The spleen is connected to the Portal System which
explains why it becomes larger when blood gets congested in the portal
vein in the presence of cirrhosis or a clot.
splenomegaly
Splenomegaly is an enlarged spleen. The spleen is located on the left
side of the abdomen just beneath the diaphragm. If you place your left
palm flat on your abdomen with the middle finger touching the
umbilicus and pointing to your right hip, the heel of your palm is
approximately in the spot where your spleen is. Splenomegaly occurs
when the spleen has a disease, or when portal hypertension develops
due to liver disease. Splenomegaly often occurs during the disease
mononucleosis (called the “kissing disease”).
Splenomegaly can cause a decrease in one’s platelet count.
Platelets are little cells that circulate in the blood just like red
blood cells that carry oxygen and white blood cells that fight
infection. Platelets plug up holes in blood vessels and form a plug so
that bleeding stops. When you cut your finger, the bleeding stops
because platelets have plugged up the holes in all the blood vessels
that were cut. In patients with splenomegaly, the platelets get
trapped in the spleen more than they should, leading to a decreased
number of platelets in the blood stream.
Stasis
Refers to things that are not moving or changing.
steroid
A hormone that controls metabolism in the body.
tacrolimus
A drug, derived from a fungus, that inhibits the body’s immune
responses. It is a standard drug for patients with organ transplants.
Most organ recipients are kept on either tacrolimus or a similar drug
called “cyclosporine” for as long as they have a functioning organ
transplant.
T cells
T cells are cells that fight infection. T cells are a kind of
lymphocytes. Lymphocytes are white blood cells that are involved in
acquired immunity. Acquired immunity is the ability to fight off
something that we were exposed to in the past. This is how vaccines
work: once the immune system is exposed to a particular structure of
an organism, it will respond vigorously the next that that organism is
encountered, usually fighting the organism off before it makes one
sick. T cells are lymphocytes that originally developed in the thymus,
an organ in the chest in front of the heart. The other lymphocytes are
B cells which develop in the spleen.
wean
To reduce slowly.
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