Regarding the article “Acetylcysteine and Fenoldopam” (June 2003:39–46), on page 40, it states that “GFR [glomerular filtration rate] . . . decreases as serum levels of creatinine increase. . . .” This implies that an increase in creatinine causes problems with GFR, thereby misleading readers.
The statement concerning serum creatinine rise referred to the known inverse relationship between serum creatinine and GFR. A rising serum creatinine equates to a reduction in GFR and vice versa. Clinicians use this value as a guide only to determine GFR. Creatinine clearance, using the Cockroft-Gualt equation, provides a more definitive value. More recently, clinicians have been using an even more specific value to estimate GFR.1