Determination Of Serum Creatinine Research Articles

Impact of removing gentamicin from an antibiotic restriction program.

Prescribing physicians at our institution were required to obtain approval from the Section of Infectious Disease for use of gentamicin sulfate and other aminoglycosides. We studied the effect of removing gentamicin from the list of restricted antibiotics, noting that gentamicin usage increased while tobramycin sulfate usage decreased during the six-month period after decontrol, compared with the previous six-month period. However, the total amount of aminoglycoside antibiotics procured by the pharmacy did not change significantly. Indications for aminoglycoside use, pretreatment evaluation of the patient (other than an initial serum creatinine determination), and rates of nephrotoxicity during treatment did not change. Decontrol of gentamicin resulted in lower aminoglycoside costs for the pharmacy without apparent compromise in patient care.

Impact of renal donation. Long-term clinical and biochemical follow-up of living donors in a single center

Forty-six renal donors who responded to a questionnaire and two additional donors with nephrotic syndrome and renal insufficiency were studied. The mean age was 46 ± 2.0 years (mean ±SE). Duration of follow-up was 6 ± 0.5 years. Serum creatinine levels increased from 1.0 ± 0.03 mg/dl before donation to 1.2 ± 0.04 mg/dl at follow-up. The incidence of proteinuria (more than 150 mg over 24 hours) was 39 percent. The serum creatinine level was 1.0 ± 0.08 mg/dl and 1.2 ± 0.06 mg/dl in the proteinuric and nonproteinuric groups, respectively. The incidence of hypertension was 31 percent with a serum creatinine level of 1.1 ± 0.11 mg/dl and 1.2 ± 0.07 mg/dl in the hypertensive and normotensive groups, respectively. One patient with nephrotic syndrome had proliferative glomerulonephritis. It is concluded that renal donation is associated with a minimal but statistically significant increment in serum creatinine levels. The incidence of mild hypertension and proteinuria is increased, but impact on renal function is minimal as assessed by serum creatinine determination.

The risks of unilateral nephrectomy: status of kidney donors 10 to 20 years postoperatively.

We received requested follow-up information from 105 (73%) of our 144 kidney donors who had undergone unilateral nephrectomy 10 to 20 years previously. Five donors had died of unrelated causes 6 or more years postoperatively. Studies in the remaining 100 donors showed that the current mean serum creatinine concentration was 1.2 mg/dl and the mean 24-hour urinary protein value was 89 mg. Hypertension (defined as 160 mm Hg or more systolic, 95 mm Hg or more diastolic, or both) was present in 19% of the donors. In a subgroup of 66 donors who had had serial serum creatinine determinations, the renal function, as estimated on the basis of these serum creatinine values, had not deteriorated with time. Thus, we consider unilateral nephrectomy in this group of patients relatively safe. Subsequent evaluation will be necessary to ascertain whether these findings prevail.

368 EVALUATION OF POTENTIAL NEPHROTOXICITY OF AMIKACIN AND TOBRAMYCIN IN PREMATURE INFANTS

The nephrotoxicity(NT) of aminoglycosides in premature infants is a still disputed problem. To assess and compare this possible side-effect of two widely used compounds, tobramycin (TB) and amikacin (AK) we determined serum creatinine (SCr), urine content of N-acetyl-beta-glucosaminidase (NAG) and blood drug levels in 28 prematures with proven or suspected infections. Fourteen infants(mean gest.age:32.1±2.1wK;mean weight: 1.650)were treated with TB,4 mg/Kg/day, and 14(inean gest.age:31.7±1.8wK; mean weight: 1.690±351 g)with AK, 15 mg/Kg/day, both divided in two doses i.m. Blood and urine samples were collected on days 1 and 8 of therapy and 5 days after its suspension. NT was defined as a rise in SCr of 0.3 mg% and/or a significant increase in urine NAG excretion on day 8 of therapy (early NT) or on day 5 after suspension (late NT). Mean trough and 1 hr postdose serum levels of TB on day 8 of therapy were 1.60±0.8 and 6.6±2 ug/ml, respectively. For AK they were 8.2±3.1 and 27.1±5.2 ug/ml. Neither drug was detected in infant sera 5 days after cessation. Both groups had similar baseline SCr and urine NAG content. No infant developed early or late NT. These data indicate that at our doses TB or AK do not result in increased levels of SCr or enzymuria in premature newborns. In addition, our results do not show any significant difference in the 2 groups and therefore, the choice between TB and AK should depend on other consideration, such as susceptibility of the pathogen or therapy cost.

Effect of various concentrations of flucytosine on the accuracy of serum creatinine determinations

Effect of various concentrations of flucytosine on the accuracy of serum creatinine determinations

Lack of evidence for interaction between tobramycin and shock in their effect on renal function

We sought to determine whether there was an interaction between aminoglycoside use and shock in their effect on renal function among seriously ill patients suspected of having gram-negative sepsis. Serial serum creatinine determinations were used to estimate changes in creatinine clearance rates in 179 patients entered onto a prospective randomized trial of tobramycin-nafcillin versus cefotaxime. A 25% decline in estimated creatinine clearance was considered to be clinically important. Univariate chi-square analysis showed that both shock (P less than 0.01) and tobramycin use (P less than 0.001) were independently associated with decline in estimated creatinine clearance. A two-way analysis of variance showed that both shock (F = 10.44, P less than 0.01) and tobramycin use (F = 42.6, P less than 0.001) continued to be significantly associated with renal dysfunction in the presence of each other, but there was no significant interaction between shock and tobramycin in their effect (F = 0.62, P less than 0.43). A multiple logistic regression with an interaction term representing the occurrence of shock and tobramycin use simultaneously yielded similar results. Our study provided no analytic evidence supporting the existence of an interaction between shock and aminoglycoside use in their effect on renal function.

Determination of Creatinine in Human Serum by Isotope Dilution-Mass Spectrometry. Definitive Methods in Clinical Chemistry, IV

Determination of Creatinine in Human Serum by Isotope Dilution-Mass Spectrometry. Definitive Methods in Clinical Chemistry, IV

Detection of renal tubular lesions after abdominal aortography and selective renal arteriography by quantitative measurements of brush-border enzymes in the urine.

Quantitative determination of brush-border enzyme excretion in the 24-hour urine is a much more sensitive index of renal tubular damage after aortography and selective renal arteriography than the conventional renal function tests such as serum creatinine and clearance determinations. Among the five brush-border enzymes which we investigated, alkaline phosphatase (AP) was the most sensitive diagnostic pointer. In 90% of hypertensive patients without detectable pre-existing renal parenchymal damage, abnormal levels of AP excretion in the urine were found on the same day as or on the day after the intra-arterial injection of contrast medium. Measurement of other brush-border enzymes does not provide any further diagnostic information. Provided there is no pre-existing renal parenchymal damage, the lesion caused by the contrast medium is transient and is usually reversed within 48 h. For the early detection of tubular lesions caused by tri-iodinated benzoic acid derivatives, AP excretion in the 24-hour urine should be measured at least twice--on the day of the contrast medium injection and on the following day.

A new enzymatic serum creatinine measurement based on an endogenous creatine-eliminating system

We describe a new colorimetric determination of serum creatinine which does not require a blank to correct for endogenous creatine. In the first reaction, creatinase (creatinase amidinohydrolase EC 3.5.3.3) and sarcosine oxidase (sarcosine: oxygen oxidoreductase (demethylating) EC 1.5.3.1) were used in the enzymatic hydrolysis of endogenous creatine to produce hydrogen peroxide. In the presence of horseradish peroxidase, 2,4-dichlorophenolsulfonate (2,4-DCPS) was converted to a colorless polymer by hydrogen peroxide. In the second reaction, creatininase (creatinine amidohydrolase EC 3.5.2.10) and 4-aminoantipyrine (4-AA) were added, and only the creatine generated from creatinine by creatininase was hydrolyzed sequentially by creatinase and sarcosine oxidase to produce hydrogen peroxide. This newly-formed hydrogen peroxide was measured at 510 nm in a coupled reaction catalyzed by peroxidase, with 2,4-DCPS/4-AA as a chromogen. The standard curve was linear up to 20 mg/dl; 40 μl of serum and 20 min were required for determination. Analytical recovery of creatinine added to either normal or abnormal sera averaged 98.5%. Within-day and day-to-day studies gave CV values of ⩽ 2.9% and ⩽ 4.8%, respectively. No significant interferences were observed with the proposed method. The results obtained by the present method correlated well with those obtained by the Jaffe procedure.

Bilirubin interference in a peroxidase-coupled procedure for creatinine eliminated by bilirubin oxidase.

A colorimetric peroxidase-coupled procedure for determination of creatinine in human serum and urine is described. A 30-s sample pre-treatment with bilirubin oxidase eliminates interference from endogenous bilirubin. The 4-aminoantipyrine-2-hydroxy-3,5-dichlorobenzenesulfonate chromogen system of this method is about fourfold more sensitive than current procedures that involve monitoring NAD(P)H and nearly fivefold more sensitive than the traditional picrate procedures. Incorporation of a sample blank eliminates positive interference from endogenous creatine. Results of the proposed procedure are somewhat lower than those of the common kinetic or equilibrium picrate techniques, as would be expected because of the effects of the well-known interferences in the latter methods.

Nylon tube-immobilized creatinine iminohydrolase and glutamate dehydrogenase in serum and urine creatinine analysis.

Immobilized enzyme nylon-tube reactors incorporating creatinine iminohyrolase (CI) and glutamate dehydrogenase (GDH) were used to assay creatinine in serum and urine. Optimum substrate concentrations for the assay were determined. The reactors were incorporated into a continuous flow system for creatinine analysis. The method was evaluated with respect to linearity, sample interaction, precision, accuracy, and analytical recovery. Comparison studies were carried out with a standard Jaffé method and the effect of interfering substances was investigated. From the results obtained, it was concluded that the assay was suitable as a simple, reliable, and specific method for serum and urine creatinine determinations.

Lack of interference of five new beta-lactam antibiotics with serum creatinine determination.

Several cephalosporins falsely elevate creatinine concentration as determined by the Jaffé reaction. We studied the in vitro effect of various concentrations of cefoperazone, ceftizoxime, ceftriaxone, ceftazidime, and azthreonam on the creatinine determination in serum, using both a manual and an automated technique. No false elevation or change in baseline creatinine concentration could be observed with any of the five antibiotics. With the use of large concentrations in serum of these beta-lactam antibiotics, we can estimate their lack of interference with creatinine determination in urine as well. Therefore, there is no need to relate the timing of blood (and urine) sampling for creatinine assay to dosage of these antibiotics.

Determination of creatinine in serum by using creatininase: enhancement of a commercial method.

Journal Article Determination of creatinine in serum by using creatininase: enhancement of a commercial method. Get access P W Landesman, P W Landesman Search for other works by this author on: Oxford Academic Google Scholar J A Lott J A Lott Search for other works by this author on: Oxford Academic Google Scholar Clinical Chemistry, Volume 29, Issue 11, 1 November 1983, Pages 2002–2003, https://doi.org/10.1093/clinchem/29.11.2002 Published: 01 November 1983

Urologic imaging and correlation with serum laboratory determinations in staging gynecologic malignancies.

The records of 526 patients with gynecologic malignancies were reviewed to determine the correlation of urologic imaging modalities with serum renal function studies in detecting ureteral obstruction at the time of initial staging. Three hundred and forty-three of these patients had excretory urograms and 305 patients had concurrent serum urea nitrogen and creatinine determinations and 261 patients had concurrent radionuclide bone scans. Twenty-six patients had concurrent sonograms. Hydronephrosis (either unilateral or bilateral) was demonstrated at urography in 11% of patients with carcinoma of the cervix and ovary, but in only two percent of patients with carcinoma of the endometrium (the latter probably due to anatomic differences and an earlier stage of disease at the time of presentation). Serum urea nitrogen and creatinine determinations were abnormal in only 30% of the patients with urinary obstruction. Although only a small proportion of patients with hydronephrosis had bone scans and sonography, these appeared to be sensitive methods of detecting obstructions, but were more expensive than urography.

Liquid-chromatographic measurement of creatinine in serum and urine.

We describe the adaptation of a "high-performance" liquid chromatographic method for determination of creatinine in serum and urine. The proposed method is simple, rapid, precise, and accurate. The retention time for creatinine can be varied simply by changing the KH2PO4 concentration in the mobile phase: acetonitrile/aqueous KH2PO4 (1/4 by vol). Within-day precision (CV) was 1.2-3.6% in serum chromatographed with an internal standard, and 2.3-2.8% in serum when an external standard was used. Between-day precision (CV) was 1.3-2.1% in serum and 1.3-2.7% in urine (with an external standard). Analytical recoveries of creatinine added to serum were 94-100% for the method with an internal standard, 95-103% with an external standard.

An enzymic creatinine assay and a direct ammonia assay in coated thin films.

We developed a thin-film enzymic assay for creatinine that makes use of creatinine iminohydrolase (EC 3.5.4.21) to convert creatinine to N-methylhydantoin and ammonia. The ammonia diffuses through a semipermeable layer and is quantitated by reaction with bromphenol blue. A paired analysis of the sample on a separate coating without the enzymic reaction measures endogenous ammonia and, for samples with normal concentrations of ammonia, allows accurate determination of serum creatinine to 150 mg/L without dilution. Results of this assay (y) compare well with those by a liquid-chromatographic comparison assay (x) by linear regression (slope = 0.935, intercept = 1.13 mg/L, r2 = 0.995). It is insensitive to many substances, such as ketones and keto acids, that interfere with conventional assays. Results of the ammonia assay (y) correlate well with those by a semi-automated enzymic assay (x) based on glutamate dehydrogenase (slope = 1.068, intercept = 17.3 mumol/L, r2 = 0.985).

Interference of Selected Second- and Third-Generation Cephalosporins with Creatinine Determination

The interference of selected second- and third-generation cephalosporins and cephalosporin-like antibiotics with serum and urine creatinine determinations was studied. Single determinations of apparent creatinine concentrations in serum, urine, and water samples were measured by three methods--manual, automated dialysis (SMAC 12/60), and direct kinetic (KDA Analyzer). Various concentrations of each cephalosporin were tested for interference with creatinine determinations. Drugs studied were cefoxitin, cefamandole, cefotaxime, ceftazidime, cefoperazone, ceftizoxime, moxalactam, ceftriaxone, and ceforanide. Cephalosporins demonstrating interference with one or more methods were further tested at concentrations representing the range of clinically achievable serum and urine drug concentrations. Cefoxitin, ceforanide, moxalactam, ceftizoxime, and ceftriaxone demonstrated significant interference in the screening tests. In subsequent testing, interference was shown at clinical concentrations of cefoxitin (all three methods) and ceforanide (manual and KDA methods). Where interference occurred, the degree varied with the assay method and the drug concentration. Recommendations are presented for serum and urine sampling for creatinine determinations in patients receiving cefoxitin and ceforanide. Based on the relationship between test interference and concentrations of these drugs achievable in patients with varying degrees of renal dysfunction, only cefoxitin and ceforanide can be expected to cause significant false elevations in vivo. To minimize interference, blood samples should be drawn at the time of minimum drug concentration.

Rate of functional deterioration in polycystic kidney disease

Renal function was evaluated in 44 patients with adult polycystic renal disease at different stages of the affection. In 38 patients single or serial determinations of the glomerular filtration rate and the effective renal plasma flow were performed. In 21 of these patients and in an additional group of six subjects, serial determinations of serum creatinine were obtained. The data show that renal function does not decrease at a constant rate between birth and endstage renal failure. It remains well preserved for many years but decreases rapidly at a later stage. The relationship between indices of renal function (glomerular filtration rate, PAH-clearance and/or reciprocal serum creatinine) and the age of the patients might be described adequately by assuming that the impairment in renal function is proportional to the growth of the cysts and that the radius of the cysts increase at a slow but constant rate. Possible contributory factors are secondary infection and hypertension.

Creatinine determined by "high-performance" liquid chromatography.

We describe a "high-performance" liquid-chromatographic procedure for determination of creatinine in serum. Creatinine is separated from other species by cation-exchange chromatography. Absorbance of the creatinine in the eluate is monitored at 234 nm. Results from this procedure on sera correspond closely to those of a manual Jaffé-reaction procedure involving use of a protein-free filtrate with additional cleanup of the sample with Lloyd's reagent. None of the 21 endogenous and exogenous substances that we screened interfered. The overall CV at 138 mumol of creatinine per liter is 1.35% and at 539 mumol/L is 0.72%.

Determination of creatinine in urine and serum by flow-injection analysis using the Jaffé reaction

A simple, modified, flow-injection procedure for the determination of creatinine in urine and deproteinized serum using the Jaffe reaction is described. The method is suitable for the flow-injection analysis of creatinine at a rate of up to 120 samples per hour with a coefficient of variation of better than 2.9%. The baseline drift is eliminated by the addition of 20% methanol to the picric acid solution.