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M Aurell

Publications and source records attributed to M Aurell.

At least 19 recordsLinked to original sources
PubMed1999

[A 100-year perspective on renal function and hypertension. Anti-renin therapy has made hypertensive renal failure a rarity].

One hundred years ago, in 1898, Professor Robert Tigerstedt, Karolinska institutet, Sweden, discovered renin. The subsequent elaboration in 1960 of the renin-angiotensin-aldosterone system signalled the start of modern hypertension research. The kidney takes part in blood pressure regulation in a number of ways. Indications are that increased renovascular resistance due to increased renin-angiotensin activity is of importance for the barostatic function of the kidneys and for the pathogenesis of human hypertension. Several commonly used, efficacious and well tolerated antihypertensive agents act by blocking the renin-angiotensin system, thus normalising kidney function. A number of current large-scale trials--utilising ACE inhibitors and angiotensin receptor antagonists--will, it is hoped, elucidate the proper role of 'anti-renin therapy' in the treatment of hypertension. Thanks to effective modern management of hypertension, renal failure due to hypertensive kidney disease is rare in Sweden today.

Acute Kidney Injury↗
PubMed1999

Drug-induced diabetes insipidus: incidence, prevention and management.

Drug-induced diabetes insipidus is always of the nephrogenic type, i.e. unresponsiveness of the kidneys to the action of antidiuretic hormone. This condition is easily diagnosed by measuring urinary concentrating capacity during a thirst test (e.g. 12 hours of water deprivation) or by administration of a modified antidiuretic hormone, desmopressin, to demonstrate the renal unresponsiveness. Drug-induced nephrogenic diabetes insipidus is not a common disorder except in patients receiving treatment with lithium salts for affective disorders where it may affect about 10% of patients treated long term (15 years). Drug-induced nephrogenic diabetes insipidus caused by other drugs usually occurs in critically ill patients in intensive care units receiving a multitude of drugs dominated by antimicrobials and cytostatics. A search of the World Health Organization's adverse effect database revealed 359 reports of drug-induced diabetes insipidus. Lithium was the most common cause (159 reports) followed by foscarnet (15) and clozapine (10). Treatment is symptomatic in most patients and the offending drug should be stopped. If urine volumes exceed 4 L/day, treatment with thiazides and amiloride has been advocated, and nonsteroidal anti-inflammatory drugs, such as indomethacin, may be tried in severe cases. Prevention of lithium-induced nephrogenic diabetes insipidus is an important aspect of the treatment of affective disorders. In patients treated long term it appears to be only partly reversible upon lithium discontinuation. Close monitoring of the treatment aiming at 12-hour trough value of 0.4 to 0.6 mmol/L is recommended. Yearly measurement of the urinary volume/day is effective in making both the patient and the physician aware of the development of the drug-induced nephrogenic diabetes insipidus. The condition is a serious adverse effect because of the risk of developing dehydration and aggravation of drug intoxications.

Animals↗
PubMed1998

[Renal artery stenosis--an underestimated cause of hypertension and renal failure?].

Although renovascular hypertension is associated with substantial cardiovascular morbidity, ultimately it is a curable disease. Early identification and appropriate treatment of renovascular hypertension may save years of antihypertensive therapy, reduce the morbidity associated with long-standing hypertension, and help to minimise the risk of renal failure. However, the main problem is to identify patients with renovascular disease suitable for treatment. This requires alertness in the clinician, and renographic screening of renal function or duplex-ultrasound scanning of renovascular circulation to augment the yield of angiographic procedures. The predominant treatment of renovascular disease today is percutaneous transluminal angioplasty, which can be used as a repeat procedure or in combination with endoluminal stenting of the stenotic renal artery.

Angioplasty, Balloon↗
PubMed1998

GFR measurement with iohexol and 51Cr-EDTA. A comparison of the two favoured GFR markers in Europe.

BACKGROUND: The aim of the present study was to compare the most commonly used GFR markers for clearance measurements, 51Cr-EDTA and iohexol, using two different methods for iohexol analysis, HPLC and X-ray fluorescence, referring both to the multiple-sample and single-sample calculations, using 51Cr-EDTA as the reference method. METHODS: Forty-nine patients with an estimated GFR >40 ml/min were included. 51Cr-EDTA and iohexol were injected simultaneously and blood samples were taken 150, 195 and 240 min after injection of the respective marker. RESULTS: The multiple-point clearances, determined from HPLC and X-ray fluorescence, compared to 51Cr-EDTA correlated highly (r=0.92 and 0.95 respectively). The results from single-point clearance comparison, iohexol measured by HPLC vs 51Cr-EDTA, yielded a correlation of r=0.91, while single-point clearance from iohexol, analysed by X-ray fluorescence, obtained a correlation of 0.93 and an intercept statistically different from origo. CONCLUSIONS: Iohexol and 51Cr-EDTA are comparable as GFR markers for multiple-point clearance measurements. The single-sample method for GFR >40 ml/min can be used with a high accuracy. The precision and accuracy of X-ray fluorescence analysis of low concentrations of iohexol were less than those of HPLC. Care should therefore be taken when using X-ray fluorescence that the injected dose of iohexol should result in a plasma concentration level of iodine of at least 0.06 mg/ml at the time of blood sampling.

Adult↗
PubMed1997

Enalapril versus metoprolol in primary hypertension--effects on the glomerular filtration rate.

BACKGROUND: Hypertension is a significant cause of end-stage renal failure and effective treatment of hypertensive will reduce the progression rate of chronic renal failure in various kidney disorders. Different classes of drugs may be more effective than others in this respect. In this study we compared the effects on the glomerular filtration rate (GFR) of the ACE-inhibitor enalapril and the betablocker metoprolol in patients with mild and moderate primary hypertension during 6 years. METHODS: Patients with GFR in the normal range (> or = 80 ml/min/1.73 m2 BSA) were included after a placebo treatment period of 4-8 weeks if diastolic blood pressure was 100-120 mm Hg. Target blood pressure was set to < 90 mm Hg diastolic. One hundred and thirty patients were randomized in an open parallel study to receive either enalapril or metoprolol. No placebo group was included. GFR was measured using the 51CR-EDTA clearance method and 81 patients completed the study. RESULTS: At inclusion, there were no significant differences regarding GFR or blood pressure between the groups. The blood pressure treatment goal was reached in all patients and was maintained during the whole observation period. A small but significant fall in GFR by 4 ml/min/1.73 m2 BSA was noted in both groups after the first year of treatment but thereafter GFR decreased by only 1 ml/min/year/1.73 m2 BSA, in both groups. Body weight, serum uric acid and triglycerides increased slightly with metoprolol treatment but no other differences between the two treatments were noted. CONCLUSIONS: With the blood pressure maintained at the same level using either enalapril or metoprolol during a 6-year study period, GFR decreased to the same extent in the two groups both during the first year and thereafter. The overall magnitude of the GFR decline approached that of the normal age-related decrease of kidney function, i.e. GFR decreased only about 1 ml/min/year. Thus, treatment with an ACE-inhibitor, enalapril, and a beta-blocker, metoprolol, protected the kidney function to the same extent in this 6 year long study in mild and moderate primary hypertension.

Adrenergic beta-Antagonists↗
PubMed1997

PGE2 production after angiotensin-converting enzyme inhibition.

Using OKT3 monoclonal antibody driven T-lymphocyte proliferation, we investigated the effects of plasma 10, 20 and 30% in cell cultures on the proliferation ex vivo after exposure to captopril or enalapril taken orally by healthy volunteers. We also studied the effects of captopril, angiotensin II and bradykinin in vitro. We observed a plasma dependent dual effect of ACE inhibition both ex vivo and in vitro and of bradykinin in vitro being a stimulated proliferation at low (10% plasma) and a suppression of proliferation at high (30% plasma). The suppression was shown to be PGE2 mediated but the nature of the stimulatory signal is unknown. Proliferation was also suppressed by angiotensin II mediated by PGE2, but angiotensin II had no stimulatory effect. The results indicate that the effects of ACE inhibition on OKT3 mAb driven T-lymphocyte proliferation is plasma dependent, class specific for ACE inhibitors and mediated by both the ACE inhibitor itself and by bradykinin. Furthermore, it was shown that indomethacin in combination with an ACE inhibitor or bradykinin converted a suppressive response into proliferation indicating an immunostimulatory activity by indomethacin.

Adult↗
PubMed1996

Remikiren (Ro 42-5892)--an orally active renin inhibitor in essential hypertension. Effects on blood pressure and the renin-angiotensin-aldosterone system.

Remikiren (Ro 42-5892) is a new orally active renin inhibitor with high potency and specificity in vitro. In the present study, the drug was given in a short-term study in patients with essential hypertension, either as monotherapy or with added hydrochlorothiazide. Following a wash-out period of at least 3 weeks and then 8 days of single-blind placebo, 29 patients with essential hypertension were given remikiren 600 mg orally for 8 days. After 4 days of remikiren, hydrochlorothiazide 12.5 mg or 25 mg or placebo was added in double-blind fashion for the last 4 days. There were no significant changes in blood pressure in patients given remikiren alone. In patients given additional hydrochlorothiazide for 4 days, a marked reduction in blood pressure was observed. Remikiren effectively inhibited the plasma renin activity 24 h post-dose, whereas angiotensin II was reduced only during the first hours after drug administration. It is concluded that remikiren is orally effective. Its antihypertensive effect during short-term administration was not significant, but when given with a diuretic, a marked potentiation occurred. Further studies are needed to establish the long-term effects of remikiren alone and in combination therapy.

Antihypertensive Agents↗
PubMed1996

Renal function on and off lithium in patients treated with lithium for 15 years or more. A controlled, prospective lithium-withdrawal study.

BACKGROUND: Controversy remains over the magnitude and reversibility of reduced renal function in long-term lithium patients. METHODS: Thirteen patients with 18 years (range 15-24) on lithium discontinued the treatment, and were re-examined twice after 5 and 9 weeks (4-16) off lithium. They were compared to a non-lithium psychiatric control group, matched for age and sex. RESULTS: Glomerular filtration rate (GFR) tended to improve from 69 (39-96) to 74 (39-94) ml/min/1.73 m2 BSA, P = 0.057, which was not significantly different from 78 (61-106 ml/min per 1.73 m2 BSA in the controls. Reduced GFR was found in only two of the lithium patients off lithium, and in none of the controls. Maximal urinary concentrating capacity did not improve at all. It was 637 (130-875) mOsm/kg H2O in the lithium patients, which was lower than 856 (705-1.035) mOsm/kg H2O (P < 0.01) in the controls. Two of the lithium patients had isosthenuria. CONCLUSIONS: Lithium patients often have an irreversible, clinically important reduction of Umax, sometimes progressing to nephrogenic diabetes insipidus, while GFR is well preserved in most patients.

Adult↗
PubMed1996

Consensus on diuresis renography for investigating the dilated upper urinary tract. Radionuclides in Nephrourology Group. Consensus Committee on Diuresis Renography.

UNLABELLED: There is great variation in technique and interpretation of diuresis renography between different establishments. METHODS: To address this problem, an International Consensus Committee was appointed by the Ninth International Symposium on Radionuclides in Nephrourology in 1994. RESULTS: The final document was produced and addressed: objectives, equipment, data acquisition, choice of radiopharmaceutical, patient preparation, position, dosage of furosemide, timing of furosemide, role of bladder catheter, duration of study, pediatric considerations, evaluation of the furosemide response, interpretation, and conclusion. CONCLUSION: The report presents a standardized approach to diuresis renography that, if adopted, will improve reproducibility between centers, discourage unacceptable practice and stimulate further discussion between nuclear medicine and urology health care professionals who treat patients with dilated and obstructed upper urinary tracts.

Adolescent↗
PubMed1996

Report of the Radionuclides in Nephrourology Committee on renal clearance.

The need for simple and accurate methods to measure renal function is self-evident. This need increases as techniques for intervention become available. The demand for evaluation of individual kidney function has increased with its role in the diagnosis and follow-up of unilateral renal disease and in decision making for conservative or surgical treatment based on residual renal function. The role of nuclear medicine in this area has been inhibited by confusion about conflicting methodologies. This report is meant to provide guidance to those centers that would like to initiate clearance procedures but have difficulty in choosing appropriate methodology.

Glomerular Filtration Rate↗
PubMed1995

Treatment of renovascular hypertension: one year results of renal angioplasty.

During the ten year period from 1981 to 1991, percutaneous transluminal renal angioplasty (PTRA) was performed in 180 renal arteries in 137 patients, where the underlying renovascular disease was fibromuscular dysplasia (FMD) in 30 patients (22%) and arteriosclerotic vascular disease (AVD) in 107 (78%). A preinterventional work-up and a re-evaluation of the patients after one year was designed for the assessment of the clinical, functional and technical outcome. Successful technical dilatation was achieved in 97% of procedures with FMD patients and in 82% of procedures with AVD patients. A beneficial effect on the blood pressure and the renal function was registered in both groups. The overall cure and improvement rate for hypertension was 86% in the FMD group and 64% in the AVD group after one year's follow-up. A significant gain in the total renal function was registered in both groups, the average increase in glomerular filtration rate being 13% (P < 0.001) for the FMD group and 11% (P < 0.001) for the AVD group one year after PTRA. Renal function was improved or unchanged in 89% of FMD patients and 74% of AVD patients. The improvement in renal function was made by the revascularized kidney. Renal vein renin investigation predicted the clinical outcome with an excellent diagnostic accuracy as no renin negative patient became normotensive, and renin positive patients, who did not turn normotensive, were in almost 90% of the cases affected by technical failure or restenosis/contralateral stenosis. Thus, the sensitivity of renal vein renin investigation was 95% and the specificity 75%. The outcome for patients with hypertension and renal insufficiency was considerably poorer than for the whole group of patients, with only a 20% success rate for hypertension, but 50% in this group had increased or unchanged GFR after intervention. The angiographic one-year follow-up revealed a recurrence rate of 6.7% for FMD and 15.1% for AVD. For the entire series of patients, the incidence of major complications was 5.4%, including one indirect fatality, while the incidence of minor complications was 5%. In conclusion, PTRA will cure or improve blood pressure in most patients with renovascular hypertension, and it preserves and even improves renal function in these patients. Complications and recurrence are in fact not very common and PTRA appears be the best first approach in all but ostial lesions for treatment of renovascular hypertension.

Angioplasty, Balloon↗