http://www.mayoclinic.org/gi-rst/mayomodel5.html

The MELD/PELD calculator screen collects data elements used in both the MELD and PELD score calculations. Please note the following:
The MELD score calculation uses:

• Serum Creatinine (mg/dl) **
• Bilirubin (mg/dl)
• INR

**For adult patients who have had dialysis twice within the last week, the creatinine value will be automatically set to 4 mg/dl.

The PELD score calculation uses:

• Albumin (g/dl)
• Bilirubin (mg/dl)
• INR
• Growth failure (based on gender, height and weight)
• Age at listing

Questions and Answers
For Patients and Families
About MELD and PELD

The United Network for Organ Sharing (UNOS), a non-profit
charitable organization, operates the Organ Procurement and
Transplantation Network (OPTN) under federal contract. On
an ongoing basis, the OPTN/UNOS continuously evaluates
new advances and research and adapts these into new organ
transplant policies to best serve patients waiting for transplants.
As part of this process, the OPTN/UNOS has
developed a new system for prioritizing patients waiting
for liver transplants. This system is based on statistical
formulas that are very accurate for predicting which
individuals are most likely to die soon from liver
disease. The MELD (Model for End Stage Liver
Disease) is used for adult patients and the PELD
(Pediatric End Stage Liver Disease Model) is used for
pediatric patients.
This document will explain the reasons for adopting
this system and how it will affect patients on the
waiting list.
 

What is MELD? How will it be used?
 

The Model for End-Stage Liver Disease (MELD) is a
numerical scale, ranging from 6 (less ill) to 40 (gravely
ill), that will be used for adult liver transplant
candidates. It gives each individual a ‘score’ (number)
based on how urgently he or she needs a liver
transplant within the next three months. The number
is calculated by a formula using three routine lab test
results:
• bilirubin, which measures how effectively the
liver excretes bile;
• INR (prothrombin time), which measures the
liver’s ability to make blood clotting factors; and
• creatinine, which measures kidney function.
(Impaired kidney function is often associated
with severe liver disease.)
The MELD score will replace the previous Status 2A,
2B and 3 categories. The status 1 category (patients
who have acute liver failure and a life expectancy of
less than 7 days without a transplant) will remain in
place as the highest priority for receiving an organ and
will not be affected by the MELD system.
A patient’s score may go up or down over time
depending on the status of his or her liver disease.
Many patients will have their MELD score assessed a
number of times while they are on the waiting list.
This will help ensure that donated livers go to the
patients in greatest need at that moment.
 

What is PELD? How does it differ from MELD?
 

Candidates under the age of 18 will be placed in
categories according to the Pediatric End-stage Liver
Disease (PELD) scoring system. PELD will replace
Status 2B and 3 for pediatric patients; Status 1 will
remain in place and will not be affected by PELD.
PELD is similar to MELD but uses some different
criteria to recognize the specific growth and
development needs of children. PELD scores may also
range higher or lower than the range of MELD scores.
The measures used are as follows:
• bilirubin, which measures how effectively the
liver excretes bile;
• INR (prothrombin time), which measures the
liver’s ability to make blood clotting factors;
• albumin, which measures the liver’s ability to
maintain nutrition;
• growth failure; and
• whether the child is less than one year old.
 

What Led To the New System?
 

For the last few years, patients needing liver transplants
have been grouped into four medical urgency
categories. The categories were based on a scoring
system that included some laboratory test results (such
as bilirubin, INR and albumin) and some symptoms of
liver disease (such as ascites and encephalopathy).
One concern with using symptoms in scoring is that
different doctors might interpret the severity of those
symptoms in different ways. In addition, this scoring
system could not easily identify which patients had
more severe liver disease and were in greater need of a
transplant.
Research showed that the MELD formula very
accurately predicts most liver patients’ short-term risk
of death without a transplant. The accuracy of the
formula did not improve when other factors were
added, such as the cause of liver failure or observed
symptoms, such as ascites, encephalopathy, or other
complications of liver diseases. The MELD and PELD
formulas are simple, objective and verifiable, and yield
consistent results whenever the score is calculated.
OPTN/UNOS committees developed the new liver
policy based on MELD and PELD. The policy
proposal was twice published for public comment. It
was approved by the OPTN/UNOS Board of
Directors in November 2001. The OPTN/UNOS
Patient Affairs Committee and patient/family
representatives on the OPTN/UNOS Board of
Directors offered key support for the new system.
 

How will waiting time be counted in the system?
 

Under the previous system, waiting time was often
used to break ties among patients of the same medical
status. Various studies, including one done by the
Institute of Medicine, report that waiting time is a poor
indicator of how urgently a patient needs a liver
transplant. This is because some patients are listed for
a transplant very early in their disease, while others are
listed only when they become much sicker.
Under the new plan, with a greater range of
MELD/PELD scores, waiting time will not have to be
used as often to break ties. Waiting time will only
determine who comes first when there are two or more
patients with the same blood type with the same
MELD or PELD score.
If a patient’s MELD or PELD score increases over
time, only the waiting time at the higher level will
count. (For example, someone who has waited 40 days
with a score of 12, and 5 days with a score of 15, would
only get credit for 5 days of waiting time at the score of
15.) Patients initially listed as a Status 1 would also
retain their waiting time if their condition improves and
they later receive a MELD/PELD score. However, if
the patient’s MELD or PELD score decreases again, he
or she would keep the waiting time gained at the higher
score. (Using the earlier example, if the patient’s score
goes from 12 to 15 and back to 12, he or she would
have 45 days of waiting time at the score of 12.)
Patients with higher MELD/PELD scores will always
be considered before those with lower scores, even if
some patients with lower scores have waited longer.
(For example, a patient waiting for one day with a score
of 30 will come ahead of a patient with a score of 29,
even if the patient with a 29 has waited longer because
the patient with a score of 30 has a higher chance of
dying on the list.)
 

What if I am on the waiting list when the system
changes?
 

A transition plan will allow you to maintain the priority
gained under the previous system. If you are an adult
Status 2A patient, you will be given priority ahead of
new adult patients listed under the MELD system for
the first 30 days after the new system is in effect. If
you do not receive a transplant within 30 days, your
MELD score will be calculated at that time, and you
will receive 30 days of waiting time at that score.
If you are a Status 2B or 3 patient, your MELD or
PELD score will be calculated at the time the new
system goes into effect. If your score stays the same or
decreases within the first year, you will keep the waiting
time gained under the previous system. If your MELD
or PELD score increases within a year, only the waiting
time in the higher status will apply (see the previous
section, “How will waiting time be counted in the
system?”).
Patients who are listed after the new system is put in
place will receive a MELD or PELD score, based on
their current lab results.
Do MELD and PELD account for all conditions?
MELD/PELD scores reflect the medical need of most
liver transplant candidates. However, there may be
special exceptions for patients with medical conditions
not covered by MELD and PELD. If your transplant
team believes your score does not reflect your need for
a transplant, they can seek a higher MELD/PELD
score than the one determined by lab tests alone.
 

Is this system likely to change?
 

As transplant professionals apply and learn from the
new system, some changes will likely be required to
better meet patients’ needs. In fact, this system is
designed to be flexible and allow improvements. In
transplantation, as in all scientific fields, new studies are
taking place all the time to learn how to save more lives
and help people live longer and better.
What if I have more questions?
If you have any further questions or concerns, you
should contact your transplant team for further
information. Additional details about the OPTN,
UNOS, allocation policy and patient informational
resources are available on the following websites:
http://www.optn.org
http://www.unos.org
http://www.patients.unos.org

LIVER TRANSPLANTATION
January 2003 . Volume 9 . Number 1
Editorial

Is the change in MELD score a better indicator of mortality than baseline
MELD score?

Patrick S. Kamath   W. Ray Kim

Liver transplantation should ideally be offered to the patient who has a
high risk of dying without liver transplantation, but who is likely to have
prolonged survival and improved quality of life posttransplantation.
Allocation systems for liver transplantation currently do not identify
patients who benefit the most from liver transplantation. Rather, the
systems are geared toward determining which patients should receive a donor
organ on a priority. Under the previous allocation system, for the vast
majority of patients, waiting time was the major determinant of liver
allocation.1 Patients disadvantaged by that system included sicker patients
with short waiting time, such as those patients with limited access to
medical resources who first receive medical attention when the liver disease
is advanced. In 1998, the Institute of Medicine suggested guidelines
de-emphasizing waiting time and mandated that the sickest patients be
highest on the priority list.2 Therefore, the emphasis changed from waiting
time to selecting the sickest patients for liver transplantation. It was
also obvious that the Child-Turcotte-Pugh classification, which categorized
patients with cirrhosis into only three groups (United Network for Organ
Sharing [UNOS] status 3, 2A, and 2B1) was not an optimal system for ranking
patients at risk for dying without liver transplantation.

The Model for End-stage Liver Disease (MELD) was developed initially to
determine risk of mortality in patients undergoing transjugular intrahepatic
portosystemic shunts (TIPS).3 This model was subsequently applied to
patients with end-stage liver disease not undergoing liver transplantation.
The model was further validated in outpatients with compensated cirrhosis
from Palermo, Italy; a cohort of patients entered into trials for treatment
of primary biliary cirrhosis; and, finally, in a historical cohort of
patients at a time when liver transplantation was not widely available.4 In
February 2002, the UNOS adopted MELD as the gauge by which to prioritize
organs for liver transplantation. However, the model had not been validated
specifically in a group of patients awaiting liver transplantation. Further,
it was not certain whether the variables used in MELD, namely the
coefficients for prothrombin time, expressed as the International Normalized
Ratio (INR), creatinine, and bilirubin were also applicable to patients
awaiting liver transplantation. Moreover, it was not known whether a certain
MELD score could be used as a cutoff to avoid futile transplantation.

In the current study, Merion et al5 have studied the utility of MELD in
determining survival in patients awaiting liver transplantation. They
studied MELD at the time of listing, updated MELD scores, as well as the
change in MELD over 30 days. They compared MELD against the
Child-Turcotte-Pugh score on which the previous allocation system, namely
UNOS status 2A, 2B, and 3, was based. They concluded that MELD was superior
to the Child-Turcotte-Pugh classification, as well as the UNOS status.
Moreover, they showed that a change in MELD over 30 days was a more
significant determinant of mortality than a one-time MELD score. For
example, they showed that for a patient with a MELD score of 25 who has a
stable score for a month ( MELD = 0), the mortality was lower than in a
patient in whom the MELD score had increased over a month to 25 (positive
MELD), but higher than in patients with a decreasing MELD score over the
previous 30 days (negative  MELD). What do these findings mean and how
should they be applied in the allocation of organs for liver
transplantation?

The MELD score will change with variations in the prothrombin time, serum
bilirubin, and serum creatinine. An increase in score generally indicates
more severe liver disease, and the MELD score may not decrease if the change
is truly related to worsening in liver function, that is, further
decompensation of the liver disease. On the other hand, MELD changes may be
transient and reversible if related to factors such as dehydration,
infection, etc. Thus, the serum creatinine level may increase with
over-enthusiastic use of diuretics, or if the patient has correctable
intrinsic disease; bilirubin and creatinine levels may increase with sepsis;
and prothrombin time may be prolonged in a patient in an intensive care unit
who is not on oral nutrition and is on systemic antibiotics, which causes
vitamin K deficiency. MELD scores, therefore, may increase because of
factors not directly related to worsening of liver disease. On the other
hand, a decrease in MELD score probably indicates correction of a reversible
factor and incorrect application of the MELD scoring system. Accordingly,
before the conclusions of this study are accepted, it is essential to know
what the cause of improving MELD or worsening MELD score in these patients
was. One would suspect that some of the patients who had a rapid increase in
MELD score over 30 days had spontaneous bacterial peritonitis resulting in
hepatorenal syndrome, or sepsis resulting in an increase in serum values for
creatinine, bilirubin, and prothrombin time, and thus an increase in the
MELD score. Similarly, those who had a decrease in MELD score probably had
reversible factors that were corrected. Merion et al suggest that  MELD be
used as a tiebreaker for organ allocation in patients on a waiting list for
liver transplantation with identical MELD scores.5 Taking the example of
three patients with a MELD score of 25, the patient at highest risk of dying
would be the patient with a positive  MELD and so should receive a liver
transplant on higher priority than the other two patients. The patient with
a stable MELD score would have the next higher risk for mortality, and the
patient with a negative  MELD would have the least risk of mortality. Should
we in fact use the  MELD as a tiebreaker when patients have identical MELD
scores, allocating the organ to the patient with positive  MELD as opposed
to stable or negative  MELD?

When the MELD system was originally developed, scores were taken in patients
hemodynamically stable and great pains were taken to ascertain that all
reversible factors were corrected. Thus, serum creatinine levels were
recorded after the patients were deemed clinically to be isovolemic.
Patients with intrinsic renal disease, as well as hepatocellular carcinoma,
were excluded. In patients with sepsis, scores were recorded after the
infection had cleared and prothrombin time, serum creatinine level, and
serum bilirubin level were stable for a week. Therefore, MELD scores may not
be as accurate an indicator of mortality in patients with cirrhosis who have
intrinsic renal disease, are dehydrated, who are septic, or who have
hepatocellular carcinoma. The implication is that it would be unusual for
MELD to improve significantly once there are no reversible factors.
Moreover, in Merion's study, the increase in MELD may be a result of
multiorgan failure. In other words, an increase in MELD may in fact be part
of the event (that is, an agonal change) rather than a predictor of death.
However, if one can be certain that reversible factors have been ruled out,
and the increase in MELD is not a preterminal event, then the  MELD could be
used to break ties for patients with identical MELD scores. If, on the other
hand, the positive  MELD is related to sepsis, such patients may have a poor
outcome after liver transplantation.

One of our concerns had been that MELD as developed in patients undergoing
TIPS may not be the perfect model to determine either mortality in patients
awaiting liver transplantation or outcome posttransplantation. The current
study, however, confirms that INR for prothrombin time, serum creatinine
level, and serum bilirubin level are the most important determinants of
survival on a waiting list. Although further fine-tuning of the allocation
system using the MELD scale is necessary, continued vigilance is also
required to make certain that patients' correct MELD scores are being
entered. This would require that each center satisfy themselves that they
have corrected reversible factors before recording MELD scores. The current
study suggests that a more rapidly increasing MELD score is likely to be
associated with increasing mortality. If findings are confirmed in
prospectively collected data sets, patients with positive  MELD should
receive organs on priority as compared with patients with identical scores
but with unchanging MELD or negative  MELD.

The MELD scale is being used to determine which patients are most at risk
for mortality and thus are at priority for receiving organs for liver
transplantation. Ideally, the system should take into account
posttransplantation outcome so that patients benefit the most from liver
transplantation and futile transplantation is avoided. In addition, data
from Merion et al suggest that there is a need to determine whether patients
with rapidly increasing MELD score have a worse outcome after liver
transplantation. More importantly, the current study suggests that the
change in the allocation system from Child-Turcotte-Pugh score to MELD score
is a step in the right direction. Using a change in MELD score rather than a
single MELD score may be one further step in finding a system whereby the
benefits of liver transplantation are maximized.


   References
1.  Lucey MR, Brown KA, Everson GT, Fung JJ, Gish R, Keeffe EB, et al.
Minimal criteria for placement of adults on the liver transplant waiting
list: A report of a national conference organized by the American Society of
Transplant Physicians and the American Association for the Study of Liver
Diseases. Liver Transpl Surg 1997;3:628-637.MEDLINE
2.  Institute of Medicine. Analysis of waiting times. In: Committee on Organ
Procurement and Transplantation Policy, (ed). Organ Procurement and
Transplantation: Assessing Current Policies and the Potential Impact of the
DHHS Final Rule. National Academy Press, Washington, DC, 1999:57-78.
3.  Malinchoc M, Kamath PS, Gordon FD, Peine CJ, Rank J, terBorg PL. A model
to predict poor survival in patients undergoing trans-jugular intrahepatic
portosystemic shunts. Hepatology 2000;31:864-871.MEDLINE
 4.  Kamath PS, Wiesner RH, Malinchoc M, Kremers W, Therneau TM, Kosberg CL,
et al. A model to predict survival in patients with end-stage liver disease.
Hepatology 2000;33:464-470.
5.  Merion RM, Wolfe RA, Dykstra DM, Leichtman AB, Gillespie B, Held PJ.
Longitudinal assessment of mortality risk among candidates for liver
transplantation. Liver Transpl 2003;9:12-18.

   Publishing and Reprint Information  From the Advanced Liver Diseases
Study Group, Division of Gastroenterology and Hepatology, Mayo Clinic and
Foundation, Rochester, MN.
Address reprint requests to Patrick S. Kamath, MD, Division of
Gastroenterology and Hepatology, Mayo Clinic and Foundation, 200 First St
SW, Rochester, MN 55905. Telephone: 507-284-1649; FAX: 507-284-0538; E-mail:
kamath.patrick@mayo.edu Copyright © 2003 by the American Association for the
Study of Liver Diseases 1527-6465/03/0901-0003$35.00/0
doi:10.1053/jlts.2003.50031

End Stage Liver Disease
by V. J. Smith, RN, BSN, MA	Article Date: 3/4/2004

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