Possible Interaction: Creatinine and Inulin

“In particular, creatinine clearance significantly overestimated both 51Cr EDTA (18.0 +/- 18.4 ml.min-1, mean difference +/- SD, P less than 0.001) and inulin clearance (26.8 +/- 17.0 ml.min-1, P less than 0.001).”

“In 54 control periods in 15 normal (anesthetized) dogs, the ratios of the clearances of creatinine and ferrocyanide to inulin (Ccr/Cin and Cfer/Cin) differed significantly from unity, averaging 0.9...”

“Thus, creatinine clearance exceeds inulin clearance, the gold standard for GFR.”

“WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT * In burn patients it has been shown ([2]), that there is a correlation between the creatinine clearance (CL(CR)) and the clearance of inulin. *”

“The overestimation of GFR by creatinine was present in 18 of 19 patients and was inversely correlated with inulin clearance (r = -0.452, p < 0.04).”

“An increased tubular secretion of creatinine accounted for the disparity between Ccr and inulin clearance in these patients.”

“The 30-min creatinine clearance and the 24-hr creatinine clearance had poorer agreement with inulin clearance.”

“ Creatinine clearance overestimated inulin clearance by 15-32% but there were no differences between control glucose and mannitol periods.”

“51Cr-EDTA clearance significantly underestimated that of inulin by a mean of -7.4 +/- … (SEM) ml/min per 1.73 m2SA (p less than 0.01) and creatinine clearance significantly … that of inulin by 37.6 +/- 3.3 (SEM) ml/min … 1.73 m2SA (p less than 0.0001).”

“These results show that 51Cr-EDTA clearance underestimates that of inulin to a similar extent in both diabetic children and healthy controls and creatinine clearance overestimates inulin clearance to a greater but similar extent in both groups.”

“ creatinine clearance values calculated over 3 h overestimated standard inulin clearance at all levels of GFR below 100 ml/min.1.73m2 (Y = 25.1 + 0.75 Cin, r = 0.77).”