Prevalence and predictors of renal artery stenosis detected by renal duplex sonography in type 2 diapetes mellitus

Diabetes mellitus [DM] is a risk factor for atherosclerosis that may lead to renal artery stenosis [RAS]. This study aimed to screen type 2 diabetic patients for presence of RAS and to identify the main predictors of its presence. The study included 473 patients [204 males and 269 females], aged 40 years or more with a well established DM of more than 5 years duration. Data about smoking, hypertension, diabetic retinopathy, ischemic heart, cercbrovascular and peripheral vascular diseases, macro and microalbuminuria, impaired kidney function and dyslipidemia were collected using history taking, physical examination and appropriate laboratory investigations. Renal ultrasonography and duplex renal scans were obtained for each patient under standardized conditions to determine the size and volume of the kidneys and to evaluate dynamics of the renal blood flow to diagnose RAS. The prevalence of RAS among all patients was 5.9%, and was 11.7% in those with hypertension. Logistic regression analysis was performed to examine and control for the joint effect of multiple factors potentially predicting presence of RAS. The odds ratio [OR] of RAS for the hypothesized predictors were determined to assess the significance of the association. There was a significant association between RAS and presence of abdominal bruit [OR=11.3], difference of length between the two kidneys [OR=3.4], age of patients [OR= 1.6] and duration of DM [OR= 1.1]. RAS is a common complication in type 2 DM. Type 2 DM patients should be scheduled for regular renal duplex check up and this may be done more frequently in patients with certain features that predict presence of RAS

Changes of the cerebral blood flow and the cognitive functions in chronic hemodialysis patients

Patients on hemodialysis [HD] therapy are increasingly at risk for cerebrovascular ishcemic stroke. Alteration in cerebral blood flow [CBF] may in part contribute to cognitive impairment in HD patients. The study aimed at screening HD patients for assessment of CBF together with identifying the patient and dialysis related factors that could influence the changes in the CBF induced by the HD session. The study included 32 patients on regular HD. Before and after HD therapy; body weight, blood pressure, heart rate, serum urea nitrogen, hemoglobin, hematocrit and acid-base parameters were measured. Before and after HD therapy, transcranial Doppler examination [TCD] was performed to determine the mean flow velocity [MFV] in the middle cerebral artery [MCA] as an indicator of CBF. Wechsler Adult Intelligence Scale [WAIS] was carried out to evaluate some of cognitive functions before and after HD session. Serum lipids for each patient were obtained once before HD. The CBF and cognitive functions were reduced significantly after HD. A statistically significant inverse correlation was found between changes in CBF and increasing age [r=0.35, p=0.05], increasing intra-dialytic weight loss [r=0.63, p<0.001], increasing levels of hemoglobin and hematocrit [r=0.36, p=0.04], and decreasing both systolic and diastolic blood pressure [r=0.34, p<0.05]. There was a statistically significant correlation between MFV in the MCA and digit symbol subtest of WAIS [r=0.43, p<0.01]. HD patients with hypotension, increased intra-dialytic fluid removal and relative increased blood viscosity had decreased CBF after HD. It could be of value using TCD to monitor the decreased CBF in HD patients at risk to manage accordingly and to improve quality of the delivered dialysis session