Measurement of glomerular filtration rate by fluorescent excitation of non-radioactive meglumine iothalamate
Guesry, P.; Kaufman, L.; Orloff, S.; Nelson, J.A.; Swann, S.; Holliday, M.
Clinical Nephrology 3(4): 134-138
1975
ISSN/ISBN: 0301-0430 PMID: 1149336 Document Number: 94711
The clearance of non-radioactive meglumine Iothalamate (Conray 60), assayed by fluorescent excitation analysis, has been shown to be a good indicator of the glomerular filtration rate (GFR). Investigations in rats by the constant infusion technique showed a good correlation with insulin clearance. In a group of ten children and one adult, we obtained excellent agreement between GFR determinations by clearance of Conray 60 and I-125 sodium Iothalamate, using the single injection technique, and taking samples from 10 min to 4 hr after injection. The decay curve was resolved into two exponential components. We have also shown that the 3 and 4 hr samples, fitted to a single exponential function, yield good agreement with GFR determinations using a double exponential model. The GFR determination method presented here is accurate, simple, cost effective, and involves no radiation exposure to the patient.