Gaspari F, Perico N, Ruggenenti P, Mosconi L, Amuchastegui
CS, Guerini E, Daina E, Remuzzi G
Plasma clearance of nonradioactive iohexol as a measure of
glomerular filtration rate
J Am Soc Nephrol
(Aug) 6:257-263 1995
Gaspari et al. describe their experience in the use of
non-radioactive contrast media as a measurement of GFR in humans in the
hope of providing an alternative method to inulin clearance. The method
involves the injection of iohexol as a single dose followed by repetitive
blood sampling to define the plasma disappearance curve of the compound. As
the latter curve becomes linear only after 120 minutes of injection of the
dye, useful sampling is required beyond this time point and at least 4
blood samples or more at sixty minutes intervals are required for accuracy.
The plasma concentration of iohexol is measured by HPLC. This procedure
would require around one hour and a half per patient studied. The data are
then fitted to either a two or one compartment model and clearance is
calculated. Compared to inulin clearance by standard methods, the iohexol
clearance gives accurate estimates of GFR, but only when several blood
samples are used over a long period of time.
Comment: The use of non-radioactive contrast media for measurement of
has been described previously by several authors. Most of these methods are
aimed at replacing inulin because of the difficulties in inulin
measurements. The adavantage of no urine collection with contrast media is
not much different than the use of the so called "single shot" inulin. The
application of these non-radioactive methods requires development of the
assay techniques in clinical laboratories, a proposition less simple than
assumed. For the practicing clinical nephrologist, these new methods offer
little benefit. Their usefulness resides in the area of clinical research.
To go back use the BACK button on your browser.
Otherwise click on the desired link to this article below:
Assessing renal function :