A critique of clinical guidelines for detection of individuals with chronic kidney disease.

Chronic kidney disease (CKD) and its association with cardiovascular mortality is increasingly regarded as a global public health problem. International efforts to combat this 'epidemic' have led to fundamental changes not only in the way we measure renal function but also how we classify and manage CKD. Clinical guidelines have established the use of estimated glomerular filtration rate (eGFR) and Kidney Disease Outcomes Quality Initiative classification of kidney disease as the cornerstones of CKD detection. The introduction of these guidelines in routine practice has had considerable impact on the large number of patients newly labelled with a chronic disease. However, it is far from clear that these patients with low GFR have intrinsic kidney disease and the vast majority will not develop end-stage renal failure. Furthermore, there is a lack of evidence that identification of low GFR can usefully be used to screen populations either for metabolic complications of kidney disease or cardiovascular risk.

Renal outcome in adults with renal insufficiency and irregular asymmetric kidneys.

BACKGROUND: The commonest cause of end-stage renal failure (ESRF) in children and young adults is congenital malformation of the kidney and urinary tract. In this retrospective review, we examine whether progression to ESRF can be predicted and whether treatment with angiotensin converting enzyme inhibitors (ACEI) can delay or prevent this. METHODS: We reviewed 78 patients with asymmetric irregular kidneys as a consequence of either primary vesico-ureteric reflux or renal dysplasia (Group 1, n = 44), or abnormal bladder function (Group 2, n = 34). Patients (median age 24 years) had an estimated GFR (eGFR) < 60 ml/min/1.73 m2 with at least 5 years of follow up (median 143 months). 48 patients received ACEI. We explored potential prognostic factors that affect the time to ESRF using Cox-regression analyses. RESULTS: At start, mean (SE) creatinine was 189 (8) mumol/l, mean eGFR 41 (1) ml/min 1.73 m2, mean proteinuria 144 (14) mg/mmol creatinine (1.7 g/24 hrs). Of 78 patients, 36 (46%) developed ESRF, but none of 19 with proteinuria less than 50 mg/mmol and only two of 18 patients with eGFR above 50 ml/min did so. Renal outcome between Groups 1 and 2 appeared similar with no evidence for a difference. A benefit in favour of treatment with ACEI was observed above an eGFR of 40 ml/min (p = 0.024). CONCLUSION: The similar outcome of the two groups supports the nephrological nature of progressive renal failure in young men born with abnormal bladders. There is a watershed GFR of 40-50 ml/min at which ACEI treatment can be successful at improving renal outcome.

Experience with efavirenz in end-stage renal disease.

There are few data on the use of highly active antiretroviral therapy in HIV-positive patients with end-stage renal disease. We describe the tolerability, safety and efficacy of an efavirenz-containing regimen in one such patient on continuous ambulatory peritoneal dialysis.

Management of uncontrolled hypertension in a nurse-led clinic compared with conventional care for patients with type 2 diabetes.

OBJECTIVE: To compare the effectiveness of a nurse-led hypertension clinic with conventional community care in general practice in the management of uncontrolled hypertension in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: We studied 120 men and women outpatient attendees (61% non-Caucasian) with type 2 diabetes and a seated blood pressure (BP) >or=140/80 mmHg. All patients were being treated for hypertension, and 71% had increased urinary albumin excretion (UAE). Patients were allocated to either a nurse-led hypertension clinic or conventional primary care. The primary outcome measure was a change in systolic BP. Secondary outcome measures were total cholesterol, HDL cholesterol, total triglycerides, HbA(1c), UAE, serum creatinine, and changes in absolute stroke and coronary heart disease (CHD) risk scores. RESULTS: The mean (95% CI) difference in the decrement of systolic BP was 12.6 mmHg (5.9-19.3) (P = 0.000) in favor of the nurse-led group, whose patients were three times more likely to a reach target systolic BP <140 mmHg compared with conventional care (P = 0.003). A significant fall in 10-year CHD (P = 0.004) and stroke risk (P = 0.000) scores occurred only in the nurse-led group. There were no significant differences in the reduction of diastolic BP or any of the other secondary outcome measures at 6 months. CONCLUSIONS: Compared with conventional care, a nurse-led hypertension clinic is a more effective intervention for patients with type 2 diabetes and uncontrolled hypertension. A target systolic BP <140 mmHg is more readily achieved and may be associated with significant reductions in 10-year cardiovascular disease risk scores.

Vitamin C improves resistance but not conduit artery endothelial function in patients with chronic renal failure.

BACKGROUND: Chronic renal failure is associated with impaired endothelium-dependent vasodilation and accelerated atherogenesis. To examine whether endogenous reactive oxygen species (ROS) modify endothelial function in renal failure, we evaluated the effect of the antioxidant vitamin C on endothelium-dependent responses in both the conduit and resistance vasculature of subjects with severe renal impairment. METHODS: Endothelial function of the forearm resistance vasculature was assessed using plethysmography to measure the dilator response to intra-arterial acetylcholine (Ach) (25 to 100 nmol/min). Endothelial function of radial and brachial arteries was assessed using vascular ultrasound to measure the dilator response to flow during reactive hyperemia [flow-mediated dilatation (FMD)]. Studies were performed before and after administration of vitamin C by intra-arterial infusion (25 mg/min) in 33 predialysis patients or by intravenous infusion (3 g) in 17 hemodialysis patients. RESULTS: Parenteral administration of vitamin C resulted in a 100-fold increase (intra-arterial studies) and a 4.5-fold increase (intravenous studies) in serum antioxidant activity. Vitamin C administration increased the dilator response to ACh in resistance vessels (P = 0.01), but did not alter the dilator response to flow in conduit vessels of either dialysis (P = 0.3) or predialysis subjects (P = 0.8). In the presence of the nitric oxide (NO) synthase inhibitor NGmonomethyl-L-arginine (L-NMMA), there was no effect of vitamin C on resistance vessel endothelial function. In all cases the dilator response to the endothelium-independent dilators was unaffected by vitamin C. CONCLUSION: Acute administration of vitamin C reduces oxidant stress in renal failure and improves NO-mediated resistance vessel dilatation.