Patients with a primary nonfunctioning liver transplant have a high mortality and usually need to receive a new transplant as quickly as possible. This needs to be distinguished from initial poor functioning of the transplant, which does not require surgery and which is eventually followed by some degree of liver function.
Tests which were found useful in assessing patients after liver transplantation were:
(1) prothrombin time
(2) factor 5 and 7 activity
(3) transaminases (AST and ALT)
|
Detection of Primary Nonfunction of Liver Transplant |
cutoff |
sensitivity |
specificity |
overall efficiency |
|
PT activity at 36 hours, in percent |
25 |
1.000 |
0.984 |
0.986 |
|
Factor 5 activity at 24 hours, in percent |
25 |
1.000 |
0.905 |
0.914 |
|
Factor 7 activity at 24 hours, in percent |
10 |
0.429 |
0.967 |
0.912 |
|
ALT at 18 hours in U/L |
1900 |
0.857 |
0.889 |
0.886 |
|
AST at 18 hours in U/L |
2600 |
0.714 |
0.936 |
0.914 |
where:
• ALT and AST are in SIU
If the 3 most efficient tests are studied, a score can be generated which correlates with the transplant status.
|
Parameter |
Finding |
Points |
|
PT activity at 36 hours, in percent |
> 25 |
0 |
|
|
15 - 25 |
1 |
|
|
< 15 |
2 |
|
Factor 5 activity at 24 hours, in percent |
> 35 |
0 |
|
|
25 - 35 |
1 |
|
|
< 25 |
2 |
|
AST at 18 hours in U/L |
< 1,500 |
0 |
|
|
1,500 - 2,200 |
1 |
|
|
> 2,200 |
2 |
score =
= (points for PT activity) + (points for Factor 5 activity) + (points for AST)
PT activity in percent concentration is obtained by determining the prothrombin time for dilutions of normal plasma:
(1) As the degree of dilution increases the PT increases
(2) To get a linear plot, log10 (dilution as percent of original) vs log10 (PT in seconds)
(3) In the US the PT is usually given in seconds, along with the PT of normal plasma in seconds
(4) The data in Houghie was analyzed; a 25% activity corresponds to 28.6 seconds; a 15% activity corresponds to 37.4 seconds
(5) On an ACL3000 using a normal control with a mean PT of 13.1 seconds, a 25% solution had a PT of 24 seconds and a 15% solution had a PT of 34 seconds
Interpretation:
• minimum score: 0
• maximum score: 6
• primary nonfunction: scores 5 or 6
• initial poor function: scores 0-4
• immediate function: scores 0-3
Specialty: Gastroenterology, Surgery, general
