Glomerular filtration rate estimation

Lenle, F, V, and Suit, P (1989). Assessment of renal function by serum creatinine and creatinine clearance Glomerular filtration rate estimated by four procedures. Our. Cfiem. 35, 2,326-2330. 

Murthy K, Stevens LA, Stark PC, Levey AS. Variation in serum creatinine assay calibration A practical application to glomerular filtration rate estimation. Kidney Int 2005 68 1884-1887. 

Another key feature of the thiazide-type diuretics is their limited efficacy in patients whose estimated renal function is reduced, such as the elderly. For example, patients with estimates of reduced renal function, such as those with a glomerular filtration rate (GFR) below 30 mL/minute, should be considered for more potent loop type diuretics such as furosemide. Clinicians often fail to either reconsider the role of thiazide diuretics prescribed to individuals whose renal function has been declining or fail to recognize the likely prevalence of renal compromise in the elderly to begin with. 

Within normal limits estimated glomerular filtration rate = 74 mL/minute... 

MDRD Formula for Estimating Glomerular Filtration Rate (from the Modification of Diet in Renal Disease Study)3... 

Levey AS, Bosch JP, Lewis JB, et al. A more accurate method to estimate glomerular filtration rate from serum creatinine A new prediction equation. Modification of Diet in Renal Disease Study Group. Ann Intern Med 1999 130 461 470. 

Creatinine clearance The rate at which creatinine is filtered across the glomerulus an estimate of glomerular filtration rate. 

The glomerular filtration rate (GFR) in normal males is estimated to be 125mL/min, and the results of the example calculation suggest that the drug is cleared by GFR. If the RCR had been less than 125 mL/min, tubular reabsorption of the drug would have been suspected. If it had been greater than 125 mL/min, tubular secretion would have been involved in the drug elimination. 

G. Schwartz, L. Feld, and D. Langford, A simple estimate of glomerular filtration rate in full term infants during the first year of life, J. Pediatr, 104, 849 (1984). 

The glomerular filtration rate (GFR) defines how much plasma water passes from the blood into the top of the nephron per minute. In health, the true GFR for a 70 kg adult is typically 100-120 ml/minute. Expressed another way, we can say that, in health, every minute each of the approximately 2 million glomeruli present in both adult kidneys filters between 0.05 and 0.06 pi of plasma water. The GFR is a good overall measure of renal function and the clinical laboratory has many ways of estimating its value. 

From a scientific point of view, glomerular filtration rate (inulin or creatinine clearance) is the best global estimate of renal function. Other parameters of interest include, but are not limited to ... 

Renal function Impairment- Ceftazidime is excreted by the kidneys, almost exclusively by glomerular filtration. In patients with impaired renal function (glomerular filtration rate (GFR) less than 50 mL/min), reduce dosage to compensate for slower excretion. In patients with suspected renal insufficiency, give an initial loading dose of 1 g. Estimate GFR to determine the appropriate maintenance dose. 

It is well known that both glomerular and tubular renal functions decline with age in at least one third of individuals. As a result there is greater variation in renal function in older subjects. Glomerular filtration rate can be predicted by creatinine clearance, which can be estimated based on measured serum creatinine (Sercr) concentration. One such formula is the Cochrane and Gault formula in which... 

Renal elimination of foreign compounds may change dramatically with increasing age by factors such as reduced renal blood flow, reduced glomerular filtration rate, reduced tubular secretory activity, and a reduction in the number of functional nephrons. It has been estimated that in humans, beginning at age 20 years, renal function declines by about 10% for each decade of life. This decline in renal excretion is particularly important for drugs such as penicillin and digoxin, which are eliminated primarily by the kidney. 

Goldberg TH, Finkelstein MS Difficulties in estimating glomerular filtration rate in the elderly. Arch Intern Med 1987 147 1430. [PMID 3453695]... 

Abbreviations BB, beta blocker BIS, bisoprolol BP, blood pressure EGFR, estimated glomerular filtration rate HCTZ, hydrochlorothiazide. 

Identify the patient at risk for CIN—For patients likely to have reduced kidney function a measurement of the SCr level and estimation of the glomerular filtration rate can be recommended, If the glomerular filtration rate is less than 50 mL/min/l, 73 m2, particularly in combination with other risk factors, consideration should be given to alternative imaging approaches. 

Schwartz GJ, Haydock GB, Edelman CM, Spitzer A (1976) A simple estimate of glomerular filtration rate in children derived from body length and plasma creatinine. Pediatrics, 51 875-878. 

Ronnhedh C, Jacquenod M, Mather LE (1996) Urineless estimation of the glomerular filtration rate and renal plasma flow in the rat. J Pharm Tox Methods 36 123-129 Sapirstein LG, Vidt DC, Mandell MJ, Hanusek G (1955) Volumes of distribution and clearances of intravenously injected creatinine in the dog. Am J Physiol 181 330-336 Sarkar SK, Holland GA, Lenkinski R et al. (1988) Renal imaging studies at 1.5 and 9.4 T effects of diuretics. Magn Reson. Med 7 117-124... 

Estimation of the glomerular filtration rate (GFR) is considered a sensitive index of functional nephron mass (Newman and Price 1999). Point measurements of the plasma levels of several endogenous small molecules (urea, creatinine, 2-(a-mannopyranosyl)-L-tryptophan) or small (less than 66 kDa) proteins (cystatin C (y-trace), prostaglandin D synthase (15-trace protein), ai-microglobulin, p2-microglobulin, and retinol binding protein) have been used to assess GFR in many species. 

Smith SA. Estimation of glomerular filtration rate from the serum creatinine concentration. Postgrad Med 1988 64 204-8. 

---