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K J Berg

Publications and source records attributed to K J Berg.

At least 19 recordsLinked to original sources
PubMed1995

Contrasting effects of angiotensin converting inhibitor and alpha-1-antagonist on albuminuria in insulin-dependent diabetes mellitus patients with nephropathy.

OBJECTIVE: The main aim of this study was to examine the effects of an angiotensin converting inhibitor, enalapril, and an alpha-1 (alpha-1) antagonist, doxazosin, on albumin excretion, renal haemodynamics and tubular function in insulin-dependent diabetes mellitus patients with nephropathy. DESIGN: The study consisted of a four-week run-in period, a four-week active treatment period, a four-week wash-out period and a second four-week active treatment period. SETTING: The study was performed in the out-patient clinic at a university hospital. SUBJECTS: Ten patients with insulin dependent diabetes mellitus with macroalbuminuria (> 200 micrograms min-1), mild to moderate hypertension (diastolic blood pressure 85-115 mmHg) and serum creatinine level below 200 mumol L-1 were included in the study. MAIN OUTCOME MEASURES: The effect of the drugs on albumin and total protein excretion, beta-2-microglobulin, proximal tubular enzyme markers and renal haemodynamics. RESULTS: Systolic and diastolic blood pressure were equally reduced by both drugs. Enalapril reduced albumin excretion from 1090 +/- 281 micrograms min-1 to 742 +/- 246 micrograms min-1 (P < 0.01) and total protein excretion from 2.0 +/- 0.4 g per 24 h to 1.3 +/- 0.4 per 24 h whereas doxazosin was without effect. Glomerular filtration rate and effective renal plasma flow were unchanged by either drug. Doxazosin increased filtration fraction from 0.21 +/- 0.02 to 0.23 +/- 0.01 (P < 0.05). The urinary excretion of the proximal enzyme markers N-acetyl-beta-glucosaminidase and alkaline phosphatase were elevated as well as urinary excretion of beta-2-microglobulin. However, neither the excretion of beta-2-microglobulin nor the enzyme markers were affected by either drug. CONCLUSIONS: Enalapril, but not doxazosin, reduces albuminuria in insulin dependent diabetes mellitus patients with nephropathy. The drugs exert differential effects on renal haemodynamics.

Adult↗
PubMed1995

Elimination of the non-ionic X-ray contrast media iodixanol and iohexol in patients with severely impaired renal function.

Iodixanol (Visipaque) and iohexol (Omnipaque) are dimeric and monomeric, respectively, non-ionic X-ray contrast media (CM), with well-characterized pharmacokinetics in healthy volunteers. This study was undertaken to study the pharmacokinetics of the contrast media in patients with severely impaired renal function. A total of 16 patients referred for preoperative abdominal angiography were randomized to form two groups of eight patients, receiving either iodixanol 320 mgI ml-1 or iohexol 350 mgI ml-1. Urine and faeces were sampled before the examination and collected quantitatively for five days afterwards, and blood samples were drawn frequently. The concentrations of iodine and contrast medium in urine and in serum, and the amount of iodine in faeces were determined. Mean baseline creatinine clearance was 13.6 and 9.9 ml min-1 1.73 m-2 in the iodixanol and iohexol groups, respectively. Patients in the iodixanol group received on average 0.34 gI per kg bodyweight (bw) and those in the iohexol group 0.39 gI per kg bw. The semilogarithmic plots of serum concentration of CM vs. time indicated elimination according to a two-compartment model. The mean elimination half-life was 23.0 h for iodixanol and 27.2 h for iohexol, and the mean apparent volume of distribution was similar for the two CM, ranging from 0.20 to 0.30 1 per kg bw. Mean plasma clearance of iodixanol was 10.4 ml min-1 1.73 m-2 and 6.9 ml min-1 1.73 m-2 for iohexol, whereas the mean renal clearances were 8.7 and 6.1 ml min-1 1.73 m-2, respectively. Mean faecal recovery was 8.2% for iodixanol and 6.1% for iohexol, and the respective figures for that in urine were 76.1 and 74.8%. Renal clearance of radiolabelled iothalamate, a marker of glomerular filtration rate (GFR), measured simultaneously, indicated that both CM were eliminated by the kidneys by glomerular filtration only. Thus, both media are suitable as GFR markers.

Aged↗
PubMed1995

Effect of iopentol on renal function and its use for calculation of glomerular filtration rate in children.

Nineteen children received 99mTc-DTPA for renography. The next day they received a simultaneous injection of the non-ionic contrast medium iopentol for urography and another injection of 99mTc-DTPA. The glomerular filtration rate (GFR) was estimated from the plasma elimination of 99mTc-DTPA as well as iopentol. Serum concentrations of creatinine and beta 2-microglobulin, and urine concentrations of creatinine, beta 2-microglobulin, alkaline phosphatase, N-acetyl-glucosaminidase, and albumin were determined. A significant reduction (12 +/- 3%) of GFR was observed after the injection of iopentol, without a subsequent rise in serum creatinine or beta 2-microglobulin. The urinary excretion of albumin and beta 2-microglobulin remained unchanged, while the excretion of alkaline phosphatase and N-acetyl-glucosaminidase was significantly increased after the urography, indicating some tubular effects of iopentol. Iopentol caused few and mild adverse events, the diagnostic yield was high, and the small changes in the renal tubular function parameters are presumed to be without clinical importance. The observed depressive effect on the GFR demands further investigations before iopentol can be recommended as a GFR-marker in children.

Child↗
PubMed1994

[Paracetamol--kidney and urinary tract. A cause of analgetic nephropathy or cancer?].

In Norway, the total consumption of non-opioid analgesics has not changed during the last ten years and was 36 defined daily doses/1,000 inhabitants/day in 1992. However, there has been a clear switch from acetyl-Salicylic acid (ASA) to paracetamol during this period. The consumption of phenazone is relatively high. Phenacetin consumption has never been a problem, and out of 3,000 renal transplanted patients at Rikshospitalet, Oslo, during the last 25 years less than 1% suffered analgesic nephropathy. It is beyond doubt that phenacetin, when taken together with either ASA or phenazone, increases the risk of urothelial cancer, especially of the renal pelvis and ureter in humans. The dramatic reduction in the incidence of analgesic nephropathy after the sale of phenacetin was prohibited has not been paralleled by a decrease in kidney or urothelial cancer. The human carcinogenicity data for paracetamol in the kidney and urinary tract is discussed. Clinical and epidemiological data, including several population based case-control studies, provide inadequate evidence of any carcinogenicity of paracetamol in the kidney or urinary tract in humans. However, chronic use of high doses of paracetamol should be avoided, probably also consumption of paracetamol in combination with ASA.

Acetaminophen↗
PubMed1994

[Treatment of paracetamol poisoning. An indication for liver transplantation?].

Development of metabolic acidosis (pH < 7.30) or the combination of encephalopathy grade III-IV, coagulopathy (PT > 100s) and oliguric renal failure are associated with a poor prognosis in paracetamol-induced fulminant liver failure. It is important to administer N-acetylcysteine as soon as possible after the overdose, but N-acetyl-cysteine also seems to improve survival when given 36-80h following ingestion. Liver transplantation has been performed in some patients with paracetamol-induced fulminant liver failure, but convincing evidence that transplantation improves survival in this group of patients is still lacking. We discuss the difficulties met in deciding if and when to perform liver transplantation. Renal failure may develop some days after paracetamol poisoning, even in the absence of severe liver damage, and haemofiltration and haemodialysis may be necessary.

Acetaminophen↗
PubMed1994

Improvement of blood glucose control in IDDM patients retards the progression of morphological changes in early diabetic nephropathy.

We investigated in a randomized, prospective study the influence of improved blood glucose control during 2-3 years in young insulin-dependent diabetic (IDDM) patients with microalbuminuria, which is indicative of early nephropathy. Patients were randomized either to intensive treatment by continuous subcutaneous insulin infusion (CSII) (n = 9) or CT (n = 9). Kidney biopsies were taken at baseline and after 26-34 months. End points were structural changes in the glomeruli. Sensitive, quantitative, morphometric methods were used. The blood glucose control improved significantly (p = 0.01) during the study in the CSII-group as glycated haemoglobin (HbA1c) fell from 10.1% ([95% CI] 8.9-11.3) to 8.6% (7.9-9.2), but not in the CT-group, 10.1% (8.3-11.9) vs 9.7% (8.7-10.8). Mean HbA1c during the study period was significantly lower in the CSII-group than in the CT-group, 8.7% (8.1-9.3) vs 9.9% (8.5-11.3), p = 0.04. Basement membrane thickness (BMT) increased in both groups, most (CT vs CSII, p = 0.03) in the CT-group: 140 nm (50-230) vs CSII: 56 nm (27-86). In the CT-group only an increase was seen in matrix/mesangial volume fraction (p = 0.006) and matrix star volume (p = 0.04). Furthermore, a positive correlation between mean HbA1c during the study and change from baseline in BMT (r = 0.70, p = 0.001) and matrix/glomerular volume fraction (r = 0.33, p = 0.09, NS) was demonstrated. Albumin excretion rate correlated significantly to BMT and most of the matrix parameters.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Contrasting short-term effects of nifedipine on glomerular and tubular functions in glomerulonephritic patients.

The short-term effects of nifedipine on glomerular hemodynamics, sieving function, and renal tubular function were assessed in 10 patients suffering from biopsy-verified chronic glomerulonephritis. Three weeks of nifedipine treatment after 2 wk of placebo significantly reduced the blood pressure from 153 +/- 6/90 +/- 3 to 139 +/- 6/84 +/- 4 mm Hg (mean +/- SE; P < 0.05). Renal vascular resistance was reduced from 0.54 +/- 0.10 to 0.46 +/- 0.08 mm Hg/mL per minute. However, GFR (44.3 +/- 7 mL/min), effective RPF (265 +/- 37 mL/min), and filtration fraction (0.17 +/- 0.01) remained unchanged. The excretion of albumin of 1,318 +/- 395 micrograms/min was not affected by nifedipine. The glomerular sieving estimated by use of the fractional dextran clearance technique revealed no significant change by nifedipine compared with placebo in the range of 30 to 60 A of hydrodynamic dextran radius. Fractional proximal reabsorption (lithium clearance method) was reduced by nifedipine from 53 +/- 5 to 46 +/- 4% (P < 0.05). Also, the excretion of beta 2-microglobulin and N-acetyl-beta-glucosaminidase increased from 10.98 +/- 4.62 to 11.86 +/- 4.74 mg/24 h (P < 0.05) and from 19.7 +/- 4.2 to 25.3 +/- 7.0 nmol/h per micromoles of creatinine (P = 0.05), respectively. It was concluded that nifedipine treatment acutely represses proximal tubular function but is without significant effect on glomerular sieving and albuminuria in these patients.

Adult↗
PubMed1994

Iodixanol in cardioangiography. A double-blind parallel comparison between iodixanol 320 mg I/ml and ioxaglate 320 mg I/ml.

Iodixanol (Visipaque) 320 mg I/ml, a non-ionic, dimeric, isotonic contrast medium, was compared to ioxaglate (Hexabrix) 320 mg I/ml in cardioangiography. One hundred and two patients with normal renal function were included in the study. The objectives were to evaluate safety, tolerability, radiographic efficacy and effects on renal function. Adverse events, discomfort, vital signs, clinical chemistry parameters, diagnostic information and radiographic density were recorded. Both contrast media had minor effects on the renal function parameters monitored. The patients who received iodixanol experienced fewer adverse events, significantly less discomfort and had a lower increase in heart rate than did the patients in the ioxaglate group. The radiographic efficacy was good in both groups. Iodixanol 320 mg I/ml is safe and effective for use in cardioangiography.

Adult↗
PubMed1994

Morphological and functional renal effects of long-term low-dose cyclosporin A treatment in patients with rheumatoid arthritis.

To explore the possible nephrotoxic effects of low-dose cyclosporin A (CyA) treatment, we analyzed the data from 10 patients, aged 35-66 years (mean 51.8 years), who had a clinical diagnosis of rheumatoid arthritis and no known kidney disease. The study protocol included consecutive kidney biopsies and a pretreatment biopsy in all cases. A second biopsy was taken after 5-20 months (mean 17.8 months) of treatment and, in seven patients, a third biopsy was performed after 30-46 months (mean 38.6 months). Evaluation of the kidney biopsies included a semiquantitative estimation of different histological parameters as well as assessment of a chronicity index (CI). Transmission electronmicroscopic examination was performed on all biopsies. There was a significant reduction of glomerular function at the time of both the second (n = 10; p < 0.01) and third (n = 7; p < 0.05) biopsies. Five patients showed an increase in CI on the second biopsy and five on the third biopsy in comparison to pretreatment values. Only one patient showed a progressive increase in CI on three consecutive biopsies. The mean CI increased on both the second (n = 10) and third (n = 7) biopsies compared with baseline, but there was no increase on the third biopsy from the second. The morphological findings were, as a rule, slight or moderate, and focal interstitial fibrosis, tubular atrophy and arteriolar hyalinosis were the most consistent findings. Although even low-dose CyA treatment may be nephrotoxic and may induce morphological alterations in the kidney, such changes do not occur in all patients and may not necessarily be progressive.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Renal effects of nonionic contrast media after cardioangiography.

A prospective double-blind randomized cardioangiographic study with iopentol and iohexol was performed in 60 patients. Glomerular filtration rate (GFR) was assessed by serum values of creatinine and beta 2-microglobulin (beta 2-MG), estimated creatinine clearance (CCr) according to Cockroft & Gault's formula, and 24 hour CCr. The urinary excretion of albumin, beta 2-MG, and of the renal tubular enzymes alkaline phosphatase (ALP) and N-acetyl-beta-glucosaminidase (NAG) was also measured. Contrary to what has been found after i.v. injections, GFR was reduced by both nonionic contrast media. Serum creatinine (S-Cr) was increased by more than 25% in 6 patients, 3 in each group. CCr was more sensitive than S-Cr and S-beta 2-MG, but this method is less precise because of risk of urine sampling errors. Estimated CCr gave no additional information to S-Cr. The urinary excretion of NAG and ALP was increased. No clinically significant differences between iopentol and iohexol were detected. No correlation was found between the changes in tubular function parameters and changes in GFR. Twenty patients were on calcium channel blockers before the investigation, but this had no protective effect on the renal function parameters.

Adult↗
PubMed1993

Early glomerulopathy is present in young, type 1 (insulin-dependent) diabetic patients with microalbuminuria.

Increased urinary albumin excretion, microalbuminuria, may be the first sign of early diabetic nephropathy. We examined glomeruli by morphometric methods in 17 patients with Type 1 (insulin-dependent) diabetes mellitus and microalbuminuria. The median age was 19 (range 18-29) years, duration of diabetes 12 (8-15) years, mean blood pressure 93 (87-115) mm Hg, glomerular filtration rate 132 (101-209) ml.min-1.1.73 m2 -2, albumin excretion rate (mean over 1 year) 32 (15-194) micrograms/min. Reference data were obtained from 11 healthy kidney donors. Mesangial volume estimates were obtained by serial sectioning in three total profiles in each of three glomeruli in diabetic patients. Basement membrane thickness and matrix volume fraction were estimated from one level per glomerulus. Two matrix parameters, matrix star volume and matrix thickness, were estimated. Interstitial volume fraction in cortex was measured by light microscopy. The morphological parameters were significantly increased in the diabetic group compared to the control group, basement membrane thickness (mean with 95% confidence intervals) was 595 nm (549-641 nm) vs 305 nm (287-325 nm), p = 0.0001; mesangial volume fraction 0.22 (0.21-0.23) vs 0.19 (0.18-0.21), p = 0.04, and matrix volume fraction 0.13 (0.12-0.13 vs 0.09 (0.08-0.10), p = 0.001. Also matrix star volume and thickness, interstitial volume fraction and mean capillary diameter were significantly increased. The intra-individual variation among glomeruli expressed as coefficient of variation was 7.4% vs 9% (basement membrane thickness) and 11.7% vs 25% (mesangial volume fraction) in the diabetic and the control group, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Iodixanol and ioxaglate in cardioangiography: a double-blind randomized phase III study.

A new non-ionic, dimeric contrast medium iodixanol (Nycomed AS, Norway) has a very low osmolality and is isotonic with blood. It has been compared with ioxaglate (Hexabrix, Laboratoire Guerbet, France) in a double-blind, randomized, parallel trial. The aims of the trial were to evaluate and compare the safety (vital signs, adverse events, discomfort and clinical-chemical parameters in blood and urine) and radiographic efficacy (diagnostic information and radiographic density) of iodixanol 320 mg I/ml vs ioxaglate (Hexabrix 320 mg I/ml) in coronary angiography and left ventriculography. Seventy-six patients referred for cardioangiography, two patients were withdrawn, 36 receiving iodixanol and 38 ioxaglate were included in the trial. Six patients (16%) in the iodixanol group and 16 (42%) patients in the ioxaglate group reported adverse events (P = 0.02). One serious adverse event occurred in the iodixanol group where a patient experienced transient cortical blindness and transitory global amnesia, but the patient recovered completely the day after the examination. Twenty-six patients reported injection-associated sensation of warmth in the iodixanol group versus 34 in the ioxaglate group (P = 0.06). Following contrast injection there were no differences between the groups regarding vital signs (ECG, heart rate, left ventricular pressures). Both contrast media were well tolerated by the kidneys, and on average only minor effects on clinical-chemical parameters in blood and urine were observed in the two groups. The radiographic efficacy was good in both groups.

Adolescent↗
PubMed1993

Iodixanol in femoral arteriography (phase III): a comparative double-blind parallel trial between iodixanol and iopromide.

Iodixanol is a new non-ionic, dimeric contrast medium (CM) which is formulated to be isotonic with blood in all clinically relevant concentrations. This is a report of a parallel, double-blind study comparing the safety and efficacy of iodixanol with iopromide (Ultravist) in aortofemoral arteriography. One hundred consecutive, eligible patients scheduled to undergo peripheral arteriography were entered into the study and randomly allocated to receive one or other CM. Radiographic quality, discomfort, adverse events, femoral blood flow and renal function were examined. Ninety-five patients were successfully included in the study. Radiographic quality (efficacy) was found to be similar in both groups. Three patients (6%) in the iodixanol group and five patients (11%) in the iopromide group reported adverse events. In this respect there was no statistically significant difference between the two groups (P = 0.48), and all adverse events were mild and transient. Forty-six (97%) patients in the iodixanol group and 45 (100%) patients in the iopromide group experienced a sensation of warmth (discomfort) in connection with one or more of the injections. There was no statistically significant difference in the frequency of discomfort in the two groups. However, the intensity of warmth was significantly milder following iodixanol than after iopromide (P = 0.003, two-sided Mantel-Haenszel test). The mean percentage increase in femoral blood flow was found to be less with iodixanol (43.4%) than with iopromide (96.3%) (P < 0.05, Student's t-test). Renal function was affected slightly after administration of both CM. Serum creatinine and creatinine clearance were affected more by iodixanol than by iopromide, while the excretion of tubular enzymes was more affected by iopromide. In conclusion, this comparison between iodixanol and iopromide showed both contrast media to be safe, effective and well tolerated and the only major difference between them was in their effect on femoral blood flow.

Aged↗
PubMed1993

Does the administration of systemic radiographic contrast media influence the acute changes in renal physiology following exposure to extracorporeal shock waves in dogs?

Five anesthetized dogs were studied for 4 to 5 hours after administration of extracorporeal shock waves to one kidney, the contralateral organ serving as control. Repetitive major doses of the nonionic monomeric radiographic contrast medium (CM) iohexol were injected intravascularly before and after application of the extracorporeal shock waves for further provocation of kidney function. Urinary excretion of electrolytes, N-acetyl-beta-glucosaminidase (NAG) and kallikrein, clearances of creatinine, inulin and para-amino-hippuric acid (PAH), serum aldosterone level and plasma renin activity (PRA) were determined. On the exposed side there was a significant fall in urinary osmolality. Effective renal plasma flow (ERPF) was reduced and glomerular filtration rate (GFR) was unchanged; thus filtration fraction (FF) was increased. Extraction of PAH was reduced, and true renal plasma flow was unchanged. Urinary osmolality on the control side was unchanged. There was a fall in ERPF and increased GFR; therefore, FF increased. The mean rise of PRA in the exposed kidney was significant after shock waves. Urine volume and urinary excretion of electrolytes and kallikrein were stable bilaterally. Relating the results to those obtained in identical canine experiments without CM, simultaneous administration of CM does not seem to significantly influence the changes in kidney function parameters caused by extracorporeal shock waves in the dog.

Acetylglucosaminidase↗
PubMed1993

Renal tubular effects of diuretics and X-ray contrast media. A comparative study of equimolar doses in healthy volunteers.

RATIONALE AND OBJECTIVES: The isotonic nonionic contrast medium iodixanol has been shown to increase urinary enzyme excretion less than the hypertonic contrast medium iopentol. The authors investigated whether this could be caused by different molar loads using enzyme excretion after diuretic administration as a model. METHODS: Matching molar doses of mannitol were given to two groups of 10 healthy volunteers. Furosemide was administered perorally to a third group of 10 persons. Urinary enzyme excretion was sequentially measured, and the results were compared to our previous findings after contrast-media administration. RESULTS: Equimolar doses of mannitol and contrast media (CM) induced similar changes in urine volume and free water clearance. Mannitol and furosemide increased the urinary excretion of N-acetyl-beta-glucosaminidase (NAG) and alkaline phosphatase (ALP) in the period 0 to 4 hours after administration, i.e. during peak diuresis, whereas both CM increased ALP significantly more, their effects still evident at 24 to 48 hours. Iodixanol had no effect on urinary NAG excretion, but iopentol increased NAG more than did mannitol. CONCLUSIONS: The early effect of CM on urinary enzyme excretion can be related, in part, to the increased diuresis, but the late effect apparent at 24 to 48 hours cannot be explained by the osmotic load of the CM.

Acetylglucosaminidase↗
PubMed1993

A double blind study to evaluate the tolerability of gadodiamide injection and its effect on renal function in patients undergoing cerebral magnetic resonance imaging.

Gadodiamide injection was administered intravenously to 28 patients with cancer undergoing cerebral magnetic resonance imaging (MRI). Two parallel groups were used to evaluate the safety of single doses of 0.1 and 0.3 mmol per kilogram body weight (kgbw). Adverse events, vital signs, blood chemistry, haematology and urinalysis were the principal measures of safety. Four patients, all in the 0.1 mmol kgbw-1 group, experienced a total of six adverse events. No adverse events were reported in the 0.3 mmol kgbw-1 group. No clinically significant changes in blood chemistry, haematology or urinalysis occurred. No significant changes in renal tubular function or glomerular filtration rate were observed after injection at either dose. Overall, this study suggests that gadodiamide injection is a safe and effective contrast medium for use in patients undergoing cerebral MRI at both the 0.1 and 0.3 mmol kgbw-1 doses.

Adult↗
PubMed1993

Iodixanol in cardioangiography in patients with coronary artery disease. Tolerability, cardiac and renal effects.

Iodixanol is a new nonionic, dimeric contrast medium. With the addition of 18 mmol/l Na+ and 0.3 mmol/l Ca++ to iodixanol 320 mg I/ml a plasma-isotonic solution was obtained. The purpose was to evaluate the suitability of iodixanol for use in cardioangiography by determining the diagnostic efficacy, patient tolerability, and cardiac and renal side-effects. Initially, 14 patients with coronary artery disease were examined using iodixanol. A double-blind, randomized study was then performed in 72 patients, comparing iodixanol and iohexol. Serum and urine were sampled before the examination, and one and 2 days after. The diagnostic information was good and the number of adverse events low with iodixanol. The patients reported significantly less of a sensation of warmth following injection of iodixanol than iohexol. Our results also indicate that iodixanol 320 mg I/ml influences renal function to a lesser degree than does iohexol 350 mg I/ml. We therefore conclude that isotonic iodixanol is a safe contrast medium for use in cardioangiography.

Adult↗