Objective-To determine whether inhibition of angiotensin converting enzyme can reduce the rate of decline in kidney function more than reducing blood pressure with other antihypertensive treatment.Design-Prospective, open randomised study lasting a mean of 2*2 years in patients with diabetic nephropathy.Setting-Three outpatient nephrology clinics.Patients-40 patients with insulin dependent diabetes and diabetic nephropathy with reduced renal function.Intervention-Antihypertensive treatment with enalapril or metoprolol, usually combined with frusemide.Main outcome measure-Rate of decline in glomerular filtration rate measured as chromium-51 edetic acid clearance.Results-Glomerular filtration rate declined a mean of 2-0 (SD 3.2) ml/min/year in the group given enalapril and 5-6 (5.9) ml/min/year in the control group. The mean arterial blood pressure during the study was 102 (5) mm Hg in the patients given enalapril and 103 (5) mm Hg in the patients given metoprolol. Urinary albumin excretion during treatment with enalapril was 60% lower than during treatment with metoprolol.

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 indi vidual 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 clear ance procedures but have difficulty in choosing appropriate meth odology.

We sought to establish the prevalence of lithium-induced end-stage renal disease in two regions of Sweden with 2.7 million inhabitants corresponding to about 30% of the Swedish population. Eighteen patients with lithium-induced end-stage renal disease were identified among the 3369 patients in the general lithium-treated population, representing a sixfold increase in prevalence compared with the general population for renal replacement therapy. All lithium-treated patients were older than 46 years at end-stage renal disease with a mean lithium treatment time of 23 years with ten patients having discontinued lithium treatment an average of 10 years before the start of renal replacement therapy. The prevalence of chronic kidney disease (defined as plasma creatinine over 150 micromol/l) in the general lithium-treated population was about 1.2% (excluding patients on renal replacement therapy). Compared with lithium-treated patients without renal failure, those with chronic kidney disease were older and most were men but, as groups, their mean serum lithium levels and psychiatric diagnoses did not differ. We found that end-stage renal disease is an uncommon but not rare consequence of long-term lithium treatment and is more prevalent than previously thought. Time on lithium was the only identified risk factor in this study, suggesting that regular monitoring of renal function in these patients is mandatory.

Reference values for glomerular filtration rate (GFR) were defined using eight reports including epidemiological studies and studies in kidney donors. Studies using both inulin and 51Cr-EDTA were included. GFR decreased with age, by 4 ml/min decade below the age of 50, and 10 ml/min decade above 50 years of age. No sex difference was found. +/- 2 SD was equal to 25 ml/min at all ages. Based on these findings a nomogram for GFR is presented. Emphasis is given to the use of plasma clearance of 51Cr-EDTA estimated with single injection technique as the new reference method for GFR measurement.

The effects of angiotensin converting enzyme inhibition with captopril were investigated in patients with diabetic nephropathy and hypertension. After nine days' treatment with captopril glomerular filtration rate was unchanged in 13 patients, whereas renal plasma flow had increased from 265 to 302 ml/min/173 ml body surface area (p

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.

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 indi vidual 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 clear ance procedures but have difficulty in choosing appropriate meth odology.

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.