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G Sterner

Publications and source records attributed to G Sterner.

At least 37 records · Page 2Linked to original sources
PubMed1996

Iohexol clearance for GFR-determination in renal failure--single or multiple plasma sampling?

The present study examined the agreement between single and multiple sample plasma clearance of iohexol, a non-ionic contrast agent, in renal failure. Sixty-five patients with varying degree of renal insufficiency received 10 ml iohexol (300 mg I/ml) i.v. and plasma samples were collected four times during the following 3-24 h. Plasma-iodine concentrations were determined by X-ray fluorescence. Predicted creatinine clearance was used to choose one of the samples for determination of single sample clearance. A single plasma specimen collected at 4 h for GFR above 50 ml/min, at 7 h for GFR between 20 and 50 ml/min, and at 24 h for GFR below 20 ml/min gave values in good agreement with those based on a four sample slope clearance. No sign of nephrotoxicity was noted after administration of the contrast agent. It is concluded that single sample plasma clearance after single injection of iohexol gives a good estimate of GFR in renal failure and is advantageous in clinical practice.

Adult↗
PubMed1995

The use of iohexol clearance to determine GFR in patients with severe chronic renal failure--a comparison between different clearance techniques.

UNLABELLED: The nonionic low-osmolar contrast medium iohexol was used as marker of glomerular filtration rate (GFR) in 53 patients with stable renal function (group I: n = 32, group II: n = 21). All the patients had clearance values < or = 30 ml.min-1.1.73 m-2 body surface; 40 patients < 20 ml.min-1.1.73 m-2 body surface. Simultaneous determinations of renal clearance and plasma clearance, both as slope clearance and single sample clearance, were performed after intravenous injection of 10 ml iohexol 300 mg iodine/ml. In groups I and II plasma was sampled early (around 3 hours) and late (up to 24 hours) after the injection. In group I urine was collected during four 40-minute periods and in group II during one 3-hour period and in group II the residual urine was estimated by ultrasound. Plasma and urine iodine concentrations were analyzed with X-ray fluorescence technique (Reanalyzer PRX90, Provalid AB, Sweden). In group II S-creatinine and tubular function test were followed to detect any signs of nephrotoxicity. In 6 anuric patients (group III) 10 ml iohexol 300 mg I/ml was injected to assess its extrarenal clearance. In groups I and II the slope clearance correlated excellently with the single sample clearance (r = 0.99) when a late plasma sample was used in both techniques. In group II, where residual urine was estimated by ultrasound, renal clearance correlated better with slope clearance than in group I (r = 0.94 vs r = 0.89). There were no signs of nephrotoxicity in the parameters noted. In group III, extrarenal plasma clearance of iohexol did not exceed 2 ml.min-1.1.73 m-2. CONCLUSION: GFR < 20 ml/min can accurately and safely be determined as renal clearance or plasma clearance of iohexol after an intravenous dose of 10 ml 300 mg I/ml. Plasma clearance techniques, which have the practical clinical advantage of no urine sampling, do at low GFR require a late plasma sample taken, for instance, 24 hours after injection of iohexol, irrespective of whether slope technique or single sample technique or one-compartment or poly-compartment models are used.

Adult↗
PubMed1994

Renal arteriovenous shunting in rejecting allograft, hydronephrosis, or haemorrhagic hypotension in the rat.

We studied the occurrence of arteriovenous (A-V) shunting in three experimental rat models, namely in rejecting allograft kidney, in uni- or bilateral ureteral obstruction, and in haemorrhagic hypotension. Isografted or sham-operated rats served as controls. Radiolabelled microspheres were injected into the renal artery and the increase in the amount of radioactivity in the lungs was considered to reflect A-V shunting in the kidney. In animals exposed to haemorrhage, with a blood pressure not less than 70% of the initial blood pressure, practically no shunting was seen. When animals were bled to a hypotension beyond the autoregulation, A-V shunting occurred inversely correlated to the degree of hypotension. In ureteral obstruction, a less marked but significant increase in shunting of microspheres to the lungs was found after 24 h of unilateral obstruction, irrespective of whether the spheres were injected into the obstructed or the contralateral kidney. Significant A-V shunting during the allograft rejection process was also demonstrated. Histologically, microspheres were found in afferent arterioles less frequently in kidneys with A-V shunting than in controls. These results indicate that A-V shunting is involved in haemorrhagic hypotension, renal graft rejection, and hydronephrosis. In the latter situation A-V shunting is probably regulated by a humoral factor.

Animals↗
PubMed1993

Determination of urinary N-acetyl-beta-glucosaminidase in patients with hypertension and renal artery stenosis.

The purpose of the study was to measure the urinary excretion of N-acetyl-beta-glucosaminidase (U-NAG) in patients suspected of having renovascular hypertension and to compare the enzyme excretion before and after active intervention with operation or percutaneous transluminal renal angioplasty (PTRA). Eighty-one patients with severe, therapy-resistant hypertension were examined with regard to renal artery stenosis (RAS). At least one significant renal artery stenosis was found in 61 patients, whilst the remaining 20 patients were classified as having essential hypertension. Enzyme levels were found to be significantly higher in RAS patients as compared with patients with severe hypertension lacking significant renal artery stenosis, 0.66 (0.41-0.91, median value, 1st and 3rd quartiles) versus 0.35 (0.27-0.54); P < 0.01. Both groups of patients had significantly higher U-NAG values than a healthy reference population (0.2, 0.13-0.27; P < 0.01). Forty of the RAS patients were randomized to surgery or PTRA and followed prospectively for 2 years. After either renal vascular surgery or PTRA a significant rise in U-NAG excretion was observed 7-10 days after treatment. Urinary NAG excretion remained elevated during long-term follow-up. It is suggested that U-NAG should be determined in patients with therapy-resistant hypertension with suspicion of renal artery stenosis.

Acetylglucosaminidase↗
PubMed1993

Plasma homocysteine in renal failure.

Plasma homocysteine in three different groups of patients with chronic renal failure (one group without dialysis, one with CAPD and one with hemodialysis) was increased compared to controls. Another group of patients with slightly reduced renal dysfunction (normal serum creatinine but reduced glomerular filtration rate) did not, however, show increase of plasma homocysteine. The clearance of homocysteine as a percentage of creatinine clearance in the three different groups of patients with chronic renal failure was also significantly increased compared to controls. Thus the clearance of homocysteine was not affected to the same extent as that of creatinine in renal failure. This may be attributed to the fact that, besides the reduced glomerular filtration rate, a depressed tubular uptake of homocysteine may occur in chronic renal failure. We were also able to show that neither in patients with varying renal function nor in controls were there any significant diurnal variation of plasma homocysteine, despite the intake of a protein-rich meal. However, after methionine loading in eight patients with severe chronic renal failure, a slight but significant increase of plasma homocysteine was noted. This indicates a disturbed metabolism with high amounts of homocysteine, which might be mainly attributed to an impaired transulphuration pathway.

Adult↗
PubMed1992

Postprandial increase in serum creatinine in renal transplant recipients.

Daily variation in serum creatinine and the effect of a protein load was studied in 18 patients with renal transplants and in 10 healthy controls. Serum creatinine was analyzed both with a standard Jaffé method and with a specific HPLC technique. Following a protein meal, a 30% increase in serum creatinine levels was noted in both groups, but the rise in absolute terms was more prominent among the transplanted patients. Urinary excretion of creatinine did not increase in the transplanted group, indicating a reduced ability to deal with the surplus creatinine in the protein meal. It is concluded that serum creatinine levels are diet-dependent and that this variation is more pronounced when renal function is reduced. Standardized blood sampling is important when following serum creatinine in renal transplant recipients from one day to the next.

Adult↗
PubMed1991

Effects of intravenous nutrition on lipoprotein metabolism, body composition, weight gain and uremic state in experimental uremia in rats.

The effect on serum lipids, lipoprotein fractions, body composition, weight gain and uremic state of including fat in intravenous nutrition was evaluated in rats with chronic uremia. Uremic rats were given high energy (1385 kJ.kg body weight-1.day-1), low nitrogen (0.6 g N.kg body weight-1.day-1) total parenteral nutrition (TPN) for 12 d with either glucose or glucose plus 30% lipids (Intralipid) as the energy source. Additional uremic and nonuremic groups were fed a standard diet orally. During TPN, serum triglyceride and cholesterol levels were slightly higher in rats fed lipid-based TPN compared to those administered glucose-based TPN or fed the oral diet; but there were no differences 8 h after feeding. The serum lipoprotein fractions showed accumulation of lipids in LDL resulting from the lipid-based TPN but no differences in VLDL. In orally fed uremic rats, more lipids were found in HDL than in the TPN-treated rats. The fractional clearance of the fat emulsion was normal and independent of the nutrition composition. Uremic rats administered lipid-based TPN for 21 d had the same weight gain as orally fed, nonuremic control rats (23 +/- 3 vs. 22 +/- 2%); glucose-based TPN did not support normal growth (10 +/- 1%). Uremic rats fed orally did not grow and retained significantly more body water than TPN-fed uremic rats. In uremic animals, lipid-based TPN also was associated with normal body composition despite significantly lower levels of carnitine in plasma, skeletal muscle and heart tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1991

Renal concentration capacity in adult patients with urinary tract infections.

The maximal urine concentration capacity was studied in patients with acute pyelonephritis and in patients with clinically diagnosed acute cystitis. In the former group renal concentration ability was reduced in 16 of 22 patients and improved in all but two patients. Among patients with symptoms of acute cystitis 6 of 22 had a concentration capacity below 2 SD of normal values. Several of these patients had raised acute phase proteins and increased their urine osmolality at follow-up indicating that cases of acute pyelonephritis could have been included. It is concluded that the wide overlap between the groups makes the maximal urinary concentration capacity a method of limited value for level diagnosis in acute UTI infection. The test should be reserved for follow-up to reveal permanent renal damage.

Acute Disease↗
PubMed1990

Enzyme immunoassay of urinary beta-hexosaminidase isoenzymes in patients with renal transplants.

beta-Hexosaminidase (NAG) and percent of NAG B were studied in twenty patients following renal transplantation. Median urinary NAG for twenty reference individuals was 0.26 U/mmol creatinine and NAG B was 24%. Urinary NAG decreased rapidly from a median of 3.7 U/mmol on the third day, to 1.2 U/mmol on the 15th day after transplantation in the patients with no major complications. The percentage of NAG B did not change significantly during this period and did not differ from the reference population. Rejection and cyclosporine toxicity were diagnosed on 17 occasions. Urinary NAG rose more than twofold in 15 of these episodes. The percentage of NAG B was slightly increased in 6 of these. Six months after discharge 17 of the renal transplants functioned well. They exhibited a marked decrease (almost normalized) of urinary NAG with no change in the percentage of NAG B.

Adult↗
PubMed1990

[Serum creatinine content of questionable value in screening for renal disease].

In a health screening programme for men aged 28-48 years, a check of serum creatinine values was included as a renal function test. Of 21,362 men screened, 114 (0.53 per cent) had two values greater than or equal to 120 mumol/l, and were further investigated vis-à-vis possible kidney disease. Of the 114 cases, renal disease including essential hypertension was present in 63, though only 29 cases had not been diagnosed previously, and in only seven cases was there no albuminuria, hypertension or history of renal disease. These findings raise doubts as to the value of analysing s-creatinine when screening for renal disease.

Adult↗