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Liver 

Transplantation 

National Digestive Diseases Information Clearinghouse 

U.S. Department 

of Health and 

Human Services 

NATIONAL 

INSTITUTES 

OF HEALTH 

What is liver 

transplantation? 

Liver transplantation is surgery to remove 

a diseased or injured liver and replace it 

with a healthy whole liver or a segment of a 

liver from another person, called a donor. 

A successful liver transplant is a life-saving 

treatment for people with liver failure, a 

condition in which the liver no longer works 

as it should. 

What does the liver do? 

The body’s largest internal organ, the 

liver has many important functions 

including 

preventing infections 

removing bacteria and toxins from 

the blood 

controlling immune responses 

processing nutrients, medications, 

and hormones 

making proteins that help the 

blood clot 

producing bile, which helps the 

body absorb fats—including 

cholesterol—and fat-soluble vitamins 

storing vitamins, minerals, fats, and 

sugars for use by the body 

A healthy liver is necessary for survival. 

A healthy liver can regenerate most of its 

own cells when they become damaged. 

Who needs a liver 

transplant? 

People with either acute or chronic liver failure may need a liver transplant to survive. 

Acute liver failure (ALF) happens suddenly. Drug-induced liver injury (DILI) 

is the leading cause of ALF in the 

United States. The most common cause 

of DILI is an overdose of acetaminophen (Tylenol). 

Chronic liver failure, also called endstage liver disease, progresses over 

months, years, or decades. Most often, 

chronic liver failure is the result of cirrhosis, a condition in which scar tissue 

replaces healthy liver tissue until the 

liver cannot function adequately. 

In U.S. adults, the most common reason for 

needing a liver transplant is cirrhosis caused 

by chronic hepatitis C, followed by cirrhosis 

caused by long-term alcohol abuse. Many 

other liver diseases also cause cirrhosis, 

including 

other forms of chronic hepatitis, including chronic hepatitis B and autoimmune 

hepatitis 

diseases that affect the bile ducts— 

tubes that carry bile from the liver to 

the gallbladder and small intestine— 

including biliary atresia, Alagille syndrome, primary biliary cirrhosis, and 

primary sclerosing cholangitis 
 

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hemochromatosis, a genetic condition in 

which iron builds up in the liver 

Wilson disease, a genetic condition in 

which copper builds up in the liver 

nonalcoholic steatohepatitis, or NASH, 

a disease caused by fat and inflammation in the liver 

In children, biliary atresia is the most common cause of liver failure and the need for a 

liver transplant. Biliary atresia is a disease in 

newborns in which the bile ducts are absent, 

damaged, or blocked. As a result, toxic bile 

builds up in the liver, resulting in cirrhosis. 

Other reasons for liver transplantation 

include cancers originating in the liver such 

as hepatocellular carcinoma, hepatoblastoma, and cholangiocarcinoma. 

What are the signs and 

symptoms of liver failure? 

The signs and symptoms of liver failure may 

include 

jaundice, a condition that causes yellowing of the skin and the whites of the eyes 

fatigue 

weakness 

loss of appetite 

nausea 

weight loss 

muscle loss 

itching 

bruising or bleeding easily because 

blood does not clot
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bleeding in the stomach 

vomiting blood 

passing black stools 

ascites, the buildup of fluid in the 

abdomen 

forgetfulness or confusion 

What is the process for 

getting a liver transplant? 

The process for getting a liver transplant 

begins with a referral by a doctor to a transplant center. People seeking a liver transplant are carefully evaluated by a team at the 

transplant center to determine whether they 

are suitable candidates for transplantation. 

The evaluation includes a complete medical history, physical examination, blood and 

urine tests, x rays and other imaging tests, 

and tests to check the function of the heart, 

lungs, and kidneys. The transplant team 

usually includes liver transplant surgeons; 

liver specialists, called hepatologists; nurses; 

transplant coordinators; social workers; a 

psychiatrist; and other specialists. A financial counselor may help with making arrangements to pay for the transplant. 

The evaluation of a transplant candidate 

typically includes assessment of 

the status of the person’s liver disease 

other diseases and conditions the person has 

the likelihood the person will survive 

the transplant operation 

the person’s ability to follow instructions and the complex medical regimen 

required after a transplant 

the person’s mental and emotional 

health
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the person’s support system 

2	� Liver Transplantation 
 

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A liver transplant selection committee 

reviews the results of the evaluation, determines whether the person meets the transplant center’s criteria for a transplant, and 

decides whether to register the person on the 

national waiting list for a transplant. 

The national waiting list is maintained by the 

United Network for Organ Sharing (UNOS), 

which administers the U.S. Organ Procurement and Transplantation Network (OPTN) 

under contract with the Health Resources 

and Services Administration (HRSA) of 

the U.S. Department of Health and Human 

Services. 

Not everyone sent to the transplant center is 

advised to have a transplant, and not every 

person who starts an evaluation is placed on 

the transplant list. While undergoing evaluation, and while waiting for a transplant, 

patients should take care of their health. 

Even if the liver transplant selection committee approves a candidate for a transplant, 

he or she may choose not to proceed with it. 

To ensure the person can make an informed 

decision about having a transplant, the transplant team provides information about the 

selection process for transplantation 

operation and recovery 

long-term demands of living with a liver 

transplant 

Scoring Systems 

When people are registered on the waiting 

list, they are assigned a score that indicates 

how urgently they need a transplant. The 

two scoring systems are the Model for Endstage Liver Disease (MELD) scoring system, 

used for people age 12 and older, and the 

Pediatric End-stage Liver Disease (PELD) 

scoring system, used for children younger 

than 12. 

MELD and PELD scores are calculated by 

computer using the results of blood tests. 

MELD scores range from 6 to 40. PELD 

scores can range from negative numbers to 

99. These scores are used to estimate the 

likelihood of dying within the next 90 days 

without a transplant. A higher score indicates a more urgent need for a liver transplant. While patients are on the national list 

wait for a transplant, their MELD or PELD 

score may go up if their condition worsens or 

go down if their condition improves. 

The MELD score is calculated using the 

results of three blood tests: 

bilirubin, which tests the amount of bile 

pigment in the blood 

creatinine, which tests kidney function 

international normalized ratio (INR), 

which tests the blood’s ability to clot 

The MELD score calculation also considers 

whether a patient who has poor kidney function is on dialysis. 

3	� Liver Transplantation 
4 Liver Transplantation

The PELD score is calculated based on 

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the results of blood tests for bilirubin, 

INR, and albumin, the major protein in 

the blood

the child’s degree of growth failure

the child’s age at time of registration

The MELD and PELD scoring systems have 

been in place since early 2002 and have 

helped reduce the size of the waiting list and 

the amount of time a person has to wait to 

receive a transplant. The MELD and PELD 

scoring systems continue to be studied to see 

whether adding other factors in the calculations can increase the ability to predict 

the risk of death without a transplant. The 

UNOS uses MELD and PELD scores in allocating livers for transplantation to patients 

on the national waiting list. More information about the MELD and PELD scoring 

systems is available from the UNOS at www.

unos.org/resources/meldPeldCalculator.asp 

and www.unos.org/SharedContentDocuments/

MELD_PELD(1).pdf.

Status 1 Patients

Critically ill patients with acute liver failure who are likely to die within a week are 

categorized as status 1 patients and are given 

highest priority for liver transplantation.

What might prevent a 

person from having a liver 

transplant?

Each transplant center has its own guidelines 

regarding eligibility for liver transplantation. 

A center might determine that a person with 

acute or chronic liver failure is not a candidate for a liver transplant if the person has

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cancer outside the liver

infection throughout the body

advanced heart or lung disease

an alcohol or drug abuse problem

AIDS

the inability to follow a treatment 

regimen

a lack of psychosocial support 

In addition, the transplant candidate may 

decide not to go forward with a transplant.
5 Liver Transplantation 

Where do donated livers 

come from? 

Most donated livers come from deceased 

donors—donors who have recently died. 

Adults usually receive the entire liver from a 

deceased donor, although a segment of the 

liver can be transplanted when the donor 

liver is too large. Because few donor livers come from children, pediatric recipients 

more often receive a portion of a liver from 

an adult donor. Occasionally, an adult liver 

is split into two portions and given to two different recipients. For example, the smaller 

left lobe may be given to a child and the 

larger right lobe given to an adult. 

Liver 

Right lobe 

Left lobe 

The liver 

A small number of liver transplants are 

performed using living donors. Most living 

donors are relatives of the recipient. In living donor transplantation, a segment of the 

donor’s healthy liver is surgically removed 

and transplanted into the recipient. Because 

a healthy liver can regenerate, the donor’s 

liver soon grows back to normal size after 

the surgery, while the segment of the liver 

that was transplanted into the recipient also 

grows to normal size. 

The entire left lobe or a portion of the left 

lobe of the liver from a living adult donor 

is usually sufficient for transplantation in a 

child. For adult recipients, the larger right 

lobe of the liver may be needed. However, 

the removal of the right lobe of the liver 

from a living donor is a challenging and 

complex surgery with significant risks to the 

donor, including death. 

According to the OPTN, about 16,000 people 

in the United States were on the waiting list 

for a liver transplant in 2008, and 6,318 liver 

transplants were performed.1 Because not 

enough donated livers are available, many 

people on the waiting list must wait a long 

time to receive a liver, and up to one out of 

10 die while on the waiting list. More donors 

are needed to meet the demand. Information about organ donation is available from 

the UNOS at www.unos.org and from the 

HRSA at www.organdonor.gov. 

1The Organ Procurement and Transplantation Network 

website. http://optn.transplant.hrsa.gov. Accessed 

October 28, 2009.
 

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How are liver donors 

and potential recipients 

matched? 

Livers for transplantation are identified and 

allocated through policies developed by the 

OPTN. The UNOS maintains a centralized computer network that links all organ 

procurement organizations and transplant 

centers in the United States. Livers are allocated to specific recipients based on the status 1 and MELD and PELD scoring systems, 

which give priority to people with the most 

urgent need for a new liver. Donors and 

recipients are matched on the basis of having 

compatible blood types and ideally should be 

similar in size. 

When a donor liver becomes available, 

information about the donor is entered into 

the UNOS computer system. The computer 

creates a ranked list of potential recipients 

with compatible blood type and size for the 

donor liver. The UNOS then offers the liver 

to the transplant team at the center with the 

patient at the top of the list. The transplant 

team has the right to decline the liver for that 

patient. The team might be forced to decline 

the donated liver if, for example, 

the patient’s condition has improved 

the patient’s condition has deteriorated 

the transplant team’s assessment is that 

the donor liver is unlikely to function 

properly in the recipient 

If a donor liver is declined, the UNOS immediately offers the donated liver to the next 

patient on the list. 

What happens during liver 

transplant surgery? 

When a suitable liver from a deceased donor 

is matched to a person who is ready to 

receive it, the surgery is scheduled as quickly 

as possible. The recipient completes presurgical testing and is prepared for surgery while 

the donor liver is obtained, transported to 

the hospital, and carefully checked to ensure 

it is suitable for transplantation. 

Liver transplant surgery is complex and can 

take up to 12 hours. The patient receiving 

the liver requires general anesthesia given 

through a breathing tube inserted into the 

windpipe, intravenous lines to provide medicine and fluids, and a catheter to drain urine. 

An incision is made in the upper abdomen, 

and the surgical team detaches the diseased 

or injured liver from blood vessels and the 

common bile duct, clamps the vessels and 

duct, and removes the liver. The team then 

attaches the recipient’s blood vessels and 

common bile duct to those in the donor 

liver. The donor liver is typically placed 

in the same location where the diseased 

or injured liver was. Tubes are sometimes 

placed around the transplanted liver to allow 

blood and fluids to drain out of the abdomen. A tube may be used to temporarily 

drain bile from the new liver into an external pouch so the bile can be measured to 

determine whether the liver is producing bile 

as it should. In cases where the recipient’s 

common bile duct cannot be connected to 

the donor’s bile duct, the donor bile duct is 

drained into a loop of small intestine. 

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After surgery, the patient goes to an anesthesia recovery area and then to an intensive 

care unit. After the patient is stabilized, 

the breathing tube used for anesthesia is 

removed and the patient moves out of intensive care and into a regular hospital room. 

Patients usually stay in the hospital from 1 to 

2 weeks after a liver transplant. 

Living donor transplants involve two surgeries performed in the same hospital. In one 

operating room, a surgical team removes 

the transplant recipient’s diseased or injured 

liver. In another operating room, another 

surgical team removes a segment of the 

donor’s healthy liver. Then the segment of 

donor liver is transplanted into the recipient. Otherwise, the surgery and recovery for 

the recipient is similar to that for a recipient 

of a liver from a deceased donor. The living donor typically remains hospitalized for 

about 1 week after surgery. 

What are the complications 

of liver transplantation? 

Possible complications of liver transplant 

surgery include 

bleeding 

damage to the bile ducts 

blood clots in the liver’s blood vessels 

infection 

rejection of the new liver by the body’s 

immune system 

side effects from the immunosuppressive medications liver transplant recipients must take to prevent rejection 

In addition, liver diseases can recur in transplanted livers. The transplanted liver can 

be damaged if, for example, a person who 

had cirrhosis caused by long-term alcohol 

abuse resumes drinking after the transplant. 

Recurrence of certain liver diseases such as 

hepatitis C can also damage the transplanted 

liver. Recurrence of hepatitis B in the transplanted liver can now be prevented. Finally, 

autoimmune diseases, such as autoimmune 

hepatitis, primary biliary cirrhosis, and primary sclerosing cholangitis, may also recur. 

If a person’s transplanted liver fails as a 

result of rejection or recurrent disease, the 

doctors on the transplant team must decide 

whether another transplant is possible. 

What is liver transplant 

rejection and how is it 

treated? 

Rejection occurs when a person’s immune 

system recognizes the transplanted liver as 

“foreign” and tries to destroy it. Rejection 

commonly occurs a week or two after a transplant, although rejection can occur at any 

time that immunosuppressive medications 

fail to control the patient’s immune reaction. 

Rejection does not always cause noticeable 

symptoms. Elevated liver enzyme levels in 

the blood may be the first sign that rejection 

is occurring. Other signs and symptoms of 

rejection may include fatigue, loss of appetite, nausea, abdominal tenderness or pain, 

fever, jaundice, dark-colored urine, or lightcolored stools. 

7	� Liver Transplantation 
 

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A liver biopsy is usually needed to verify that 

rejection is occurring in the transplanted 

liver and exclude other causes of symptoms 

or abnormal liver enzyme levels. A biopsy 

involves using a needle to remove a small 

piece of liver tissue to be examined with a 

microscope. 

Immunosuppressive medications are used 

to decrease the activity of the recipient’s 

immune response to prevent and treat rejection. Transplant recipients must take immunosuppressive medications for the rest of 

their life to prevent rejection. 

Immunosuppressive medications commonly 

given after a transplant include 

intravenous methylprednisolone (DepoMedrol, Solu-Medrol), which is given 

during and immediately after surgery, 

and prednisone (Deltasone, Sterapred), 

once oral medications can be given 

tacrolimus (Prograf) or cyclosporine 

(Neoral, Sandimmune)
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sirolimus (Rapamune), which cannot 

be used for several months after a liver 

transplant because it can cause blood 

clots in the major artery providing blood 

to the transplanted liver and prevents 

the surgical wounds from healing; however, sirolimus is safe once the artery 

and wounds have completely healed 

mycophenolate mofetil (CellCept), 

mycophenolic acid (Myfortic), and 

azathioprine (Azasan, Imuran), which 

may be given along with cyclosporine or 

tacrolimus 

In general, a transplant recipient needs 

to take more medications during the first 

several months after a transplant, and later 

some medications may be eliminated or 

doses may be lowered to minimize side 

effects. One year after transplantation, 

many patients require only tacrolimus, 

cyclosporine, or sirolimus. 

Immunosuppressive medications can have 

significant side effects. By suppressing the 

immune system, the medications can make 

patients more susceptible to infections. 

Other possible side effects include 

weight gain—prednisone 

diabetes—tacrolimus, cyclosporine 

high blood pressure—prednisone, tacrolimus, cyclosporine, sirolimus 

high blood cholesterol or triglycerides— 

cyclosporine, sirolimus 

osteoporosis—prednisone 

kidney damage—tacrolimus, 

cyclosporine, sirolimus
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Long-term use of immunosuppressive 

medications can also increase a person’s risk 

of developing cancers of the skin and other 

sites. Yearly monitoring is required to detect 

any cancers at an early, treatable stage. 

A number of medications, as well as grapefruit and grapefruit juice, can increase 

or decrease the levels of tacrolimus, 

cyclosporine, and sirolimus in the body. To 

prevent complications caused by the levels 

of these immunosuppressive medications 

becoming either too high or too low, people 

taking these medications should avoid grapefruit and discuss any new medications— 

prescribed or over-the-counter—with their 

transplant team. 

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What is the outlook for 

people who have a liver 

transplant? 

Most liver transplants are successful. About 

80 to 85 percent of transplanted livers are 

functioning after 1 year.2 People who have a 

liver transplant are usually able to return to 

normal activities after recovering for several 

months. 

Liver transplant recipients receive intensive 

medical follow-up during the first year after a 

transplant. They have regular blood tests to 

check whether the liver is being damaged by 

rejection, infections, or problems with blood 

vessels or bile ducts. 

To help achieve a good outcome after a liver 

transplant, recipients need to 

follow instructions for taking 

medications 

keep all medical appointments 

avoid people who are ill and let their 

doctor know when they are ill 

learn to recognize the signs of rejection 

and infection and report them promptly 

to their doctor 

maintain a healthy lifestyle by making 

healthy food choices, exercising, not 

smoking, and not drinking alcohol 

22008 annual report of the U.S. Organ Procurement 

and Transplantation Network and the Scientific 

Registry of Transplant Recipients: transplant 

data 1997–2007. Health Resources and Services 

Administration, Healthcare Systems Bureau, Division 

of Transplantation website. www.ustransplant.org/ 

annual_reports/current. Accessed October 28, 2009. 

9	� Liver Transplantation 

Points to Remember 

Liver transplantation is surgery to 

remove a diseased or injured liver and 

replace it with a healthy whole liver or a 

segment of a liver from another person, 

called a donor. 

People with either acute or chronic liver 

failure may need a liver transplant to 

survive. 

In adults, chronic liver failure due to cirrhosis caused by hepatitis C is the most 

common reason for liver transplantation 

in the United States. The second most 

common reason is cirrhosis caused by 

long-term alcohol abuse. 

In children, biliary atresia is the most 

common cause of liver failure and the 

need for a liver transplant. 

The process for getting a liver transplant begins with referral to a transplant 

center, where a transplant team carefully evaluates candidates to determine 

whether they are suitable candidates for 

transplantation. The transplant center’s 

liver transplant selection committee 

decides whether to register a candidate on the national waiting list for a 

transplant. 

The national waiting list is maintained 

by the United Network for Organ Sharing (UNOS). The UNOS administers 

the U.S. Organ Procurement and Transplantation Network (OPTN) under 

contract with the Health Resources and 

Services Administration (HRSA) of the 

U.S. Department of Health and Human 

Services. 

People on the waiting list are assigned 

a score that indicates how urgently they 

need a transplant. The two scoring 

systems are the Model for End-stage 

Liver Disease (MELD) scoring system, 

used for people age 12 and older, and 
 

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the Pediatric End-stage Liver Disease 

(PELD) scoring system, used for children younger than 12. A higher score 

indicates a more urgent need for a liver 

transplant. 

Critically ill patients with acute liver 

failure who are likely to die within a 

week are categorized as status 1 patients 

and are given highest priority for liver 

transplantation. 

Most livers for transplantation come 

from deceased donors. A small number 

of transplants involve living donors, who 

donate part of their liver, usually to a 

family member. 

Liver transplant surgery is complex 

and can take up to 12 hours. Patients 

usually stay in the hospital from 1 to 

2 weeks after a liver transplant. 

Complications after liver transplant 

surgery may include bleeding, bile leaks, 

blood clots in the liver’s blood vessels, 

infection, rejection of the new liver, and 

side effects from immunosuppressive 

medications. 

Liver transplant recipients must take 

immunosuppressive medications for the 

rest of their life. 

Most liver transplants are successful. 

People who have a liver transplant are 

usually able to return to normal activities after recovering for several months. 

Hope through Research 

The National Institute of Diabetes and 

Digestive and Kidney Diseases (NIDDK), 

through its Liver Disease Research Branch, 

focuses and accelerates research on liver 

disease within the Institute and helps coordinate and stimulate liver-related research 

across the National Institutes of Health and 

within other federal agencies. The NIDDK 

aims to improve long-term success and organ 

availability for liver transplantation as a 

treatment of acute and chronic liver failure 

and to provide a means to reliably diagnose, manage, treat, and prevent its major 

complications. 

The NIDDK supports and conducts a wide 

variety of research related to liver diseases, 

liver failure, and liver transplantation. 

Examples of studies funded by the NIDDK 

include those investigating adult-to-adult 

living donor liver transplantation, ways to 

prevent the recurrence of hepatitis C after 

liver transplantation, and acute liver failure 

in children. 

Participants in clinical trials can play a more 

active role in their own health care, gain 

access to new research treatments before 

they are widely available, and help others 

by contributing to medical research. For 

information about current studies, visit 

www.ClinicalTrials.gov. 

10 Liver Transplantation 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

For More Information 

American Association for the Study of 

Liver Diseases 

1001 North Fairfax, Suite 400 

Alexandria, VA 22314 

Phone: 703–299–9766 

Fax: 703–299–9622 

Email: aasld@aasld.org 

Internet: www.aasld.org 

American Liver Foundation 

75 Maiden Lane, Suite 603 

New York, NY 10038–4810 

Phone: 1–800–GO–LIVER 

(1–800–465–4837) or 212–668–1000 

Fax: 212–483–8179 

Internet: www.liverfoundation.org 

Hepatitis Foundation International 

504 Blick Drive 

Silver Spring, MD 20904 

Phone: 1–800–891–0707 or 301–622–4200 

Fax: 301–622–4702 

Email: hfi@comcast.net 

Internet: www.hepfi.org 

Organ Procurement and Transplantation 

Network 

Internet: http://optn.transplant.hrsa.gov 

United Network for Organ Sharing 

P.O. Box 2484 

Richmond, VA 23218 

Phone: 1–888–894–6361 or 804–782–4800 

Internet: www.unos.org 

Acknowledgments 

Publications produced by the Clearinghouse 

are carefully reviewed by both NIDDK scientists and outside experts. This publication 

was reviewed by Ann Harper, United Network for Organ Sharing; Michael R. Lucey, 

M.D., University of Wisconsin–Madison; and 

John M. Vierling, M.D., Baylor College of 

Medicine, Houston. 

You may also find additional information about this 

topic by visiting MedlinePlus at www.medlineplus.gov. 

This publication may contain information about 

medications. When prepared, this publication 

included the most current information available. 

For updates or for questions about any medications, 

contact the U.S. Food and Drug Administration 

toll-free at 1–888–INFO–FDA (1–888–463–6332) or 

visit www.fda.gov. Consult your doctor for more 

information. 

The U.S. Government does not endorse or favor any 

specific commercial product or company. Trade, 

proprietary, or company names appearing in this 

document are used only because they are considered 

necessary in the context of the information provided. 

If a product is not mentioned, the omission does not 

mean or imply that the product is unsatisfactory. 

11 Liver Transplantation 
 

 

 

 

National Digestive Diseases 

Information Clearinghouse 

2 Information Way 

Bethesda, MD 20892–3570 

Phone: 1–800–891–5389 

TTY: 1–866–569–1162 

Fax: 703–738–4929 

Email: nddic@info.niddk.nih.gov 

Internet: www.digestive.niddk.nih.gov 

The National Digestive Diseases Information 

Clearinghouse (NDDIC) is a service of the 

National Institute of Diabetes and Digestive 

and Kidney Diseases (NIDDK). The 

NIDDK is part of the National Institutes of 

Health of the U.S. Department of Health 

and Human Services. Established in 1980, 

the Clearinghouse provides information 

about digestive diseases to people with 

digestive disorders and to their families, 

health care professionals, and the public. 

The NDDIC answers inquiries, develops and 

distributes publications, and works closely 

with professional and patient organizations 

and Government agencies to coordinate 

resources about digestive diseases. 

This publication is not copyrighted. The Clearinghouse 

encourages users of this publication to duplicate and 

distribute as many copies as desired. 

This publication is available at 

www.digestive.niddk.nih.gov. 

U.S. DEPARTMENT OF HEALTH 

AND HUMAN SERVICES 

National Institutes of Health 

NIH Publication No. 10–4637 

June 2010