Rare Diseases Symptoms Automatic Extraction
Home
A random Abstract
Our Project
Our Team
Anti-platelet factor 4/heparin antibodies in patients with impaired graft function after liver transplantation.
[heparin-induced thrombocytopenia]
Heparin
,
the
standard
perioperative
anticoagulant
for
the
prevention
of
graft
vessel
thrombosis
in
patients
undergoing
liver
transplantation
(
LT
)
,
binds
to
the
chemokine
platelet
factor
4
(
PF
4
)
.
Antibodies
that
are
formed
against
the
resulting
PF
4
/
heparin
complexes
can
induce
heparin-induced
thrombocytopenia
.
LT
is
a
clinical
situation
that
allows
the
study
of
T
-
cell
dependency
of
immune
responses
because
T
-
cell
function
is
largely
suppressed
pharmacologically
in
these
patients
to
prevent
graft
rejection
.
To
investigate
the
immune
response
against
PF
4
/
heparin
complexes
in
patients
undergoing
LT
.
In
this
prospective
cohort
study
,
38
consecutive
patients
undergoing
LT
were
systematically
screened
for
anti-
PF
4
/
heparin
antibodies
(
enzyme
immunoassay
and
heparin-induced
platelet
aggregation
assay
)
,
platelet
count
,
liver
function
,
and
engraftment
.
At
baseline
,
5
(
13
%
)
of
38
patients
tested
positive
for
anti-
PF
4
/
heparin
IgG
(
non-
platelet
-activating
)
antibodies
.
By
day
20
,
an
additional
5
(
15
%
)
of
33
patients
seroconverted
for
immunoglobulin
G
(
two
platelet
-activating
)
antibodies
.
No
patient
developed
clinical
heparin-induced
thrombocytopenia
.
Two
of
six
patients
with
graft
function
failure
had
anti-
PF
4
/
heparin
IgG
antibodies
at
the
time
of
graft
function
failure
.
Graft
liver
biopsy
samples
from
these
patients
showed
thrombotic
occlusions
of
the
microcirculation
.
Anti-
PF
4
/
heparin
IgG
antibodies
are
generated
despite
strong
pharmacologic
suppression
of
T
cells
,
indicating
that
T
cells
likely
have
a
limited
role
in
the
immune
response
to
PF
4
/
heparin
complexes
in
humans
.