Summary
We investigated tissue factor pathway inhibitor (TFPI) levels in 44 non-dialysis uremic
patients and 36 chronic dialysis patients, as well as the changes of TFPI levels during
hemodialysis sessions using heparin (n = 14), low molecular weight heparin (n = 7),
nafamostat mesilate (n = 5), and argatroban (n = 2). In non-dialysis uremic patients,
TFPI levels increased (mean ± SD: 178 ± 37% of control pooled plasma) along with the
impairment of renal function. In chronic hemodialysis patients, TFPI levels were even
higher (265 ± 72%) before dialysis, but did not depend on the etiology of renal failure
(diabetic or non-diabetic), the interval between dialysis sessions (twice or three
times a week), and the duration of hemodialysis. During hemodialysis sessions using
heparin, TFPI levels increased 1.2-to 3.5-fold compared with the level before hemodialysis
and the degree of increase in TFPI was correlated with the heparin concentration (r
= 0.648, p = 0.0001, n = 29). During dialysis sessions using low molecular weight
heparin, TFPI levels also increased, but the change was less marked than during dialysis
with heparin. TFPI levels did not change during dialysis sessions using nafamostat
mesilate or argatroban. In conclusion, TFPI levels were increased by renal failure
and by long-term repeated injection of heparin, but the hemodialysis procedure itself
did not alter the TFPI level.