title: Capillary electrophoresis for the determination of glomerular filtration rate using nonradioactive iohexol.
abstract: High-performance liquid chromatography (HPLC) has been used as an alternative to the isotopic method to calculate glomerular filtration rate (GFR). With the HPLC method, serum iohexol or iothalamate levels are measured, and the plasma clearance rate of the compound is used as a surrogate for GFR. However, HPLC is a labor-intensive procedure, which limits its usefulness in the clinical setting. Capillary electrophoresis, a newer technique in which electrophoretic separations are performed in capillary tubes, is easier and faster than HPLC. We used capillary electrophoresis for the determination of serum iohexol levels and the calculation of GFR. Patients underwent a simultaneous 125I-iothalamate clearance test and a plasma iohexol clearance test to determine GFR. Mean GFR (+/-SD) was 70.9 +/- 29.9 mL/min (range, 14.5 to 131 mL/min) in 52 patients as determined by standard iothalamate clearance methods. For iohexol clearance, the correlation coefficient and standard error were 0.93 and 10.9 mL/min, respectively, using capillary electrophoresis compared with the iothalamate method. Capillary electrophoresis is a simple, rapid method that can be used to calculate GFR and provides results at least as accurate as those obtained by HPLC and x-ray fluorescence.
authors.affiliation: Department of Internal Medicine/Nephrology, Baptist Hospital, Bowman Gray School of Medicine of Wake Forest University, Winston-Salem, NC 27157-1053, USA.
authors.forename: M V
authors.initials: MV
authors.lastname: Rocco
authors.forename: V M
authors.initials: VM
authors.lastname: Buckalew
authors.forename: L C
authors.initials: LC
authors.lastname: Moore
authors.forename: Z K
authors.initials: ZK
authors.lastname: Shihabi
mesh_terms: D000328:Adult; D000368:Aged; D002851:Chromatography, High Pressure Liquid / Q000379:methods / Q000706:statistics & numerical data; D003287:Contrast Media / Q000032:analysis / Q000493:pharmacokinetics; D019075:Electrophoresis, Capillary / Q000379:methods / Q000706:statistics & numerical data; D005069:Evaluation Studies as Topic; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007457:Iodine Radioisotopes / Q000032:analysis / Q000493:pharmacokinetics; D007472:Iohexol / Q000032:analysis / Q000493:pharmacokinetics; D007483:Iothalamic Acid / Q000032:analysis / Q000493:pharmacokinetics; D008297:Male; D008657:Metabolic Clearance Rate; D008875:Middle Aged; D013997:Time Factors
chemical_list: D003287:Contrast Media; D007457:Iodine Radioisotopes; D007483:Iothalamic Acid; D007472:Iohexol