Silent cerebral infarction in hemodialysis patients: possible predictors for vascular events

We designed this study on hemodialysis [HD] patients to estimate the prevalence of silent brain infarction [SBI]; to evaluate the cardiovascular risk factors for SCI; and to investigate whether or not SCI is associated with clinical vascular events. Fifty HD patients who had no past history of stroke or TIA were included in this prospective study. We followed these patients for two years to record any vascular events related to cardiovascular or cerebrovacsular diseases. All patients underwent CT or MRI on the brain to define any silent brain infarcts. We investigated the prognostic role of SCI in cerebral, cardiac and vascular events by using Cox proportional hazards analysis. SCI was detected in 16 patients out of 50 HD patients with a percentage of 32%. During follow up period, vascular events were detected in ten patients after two years of follow up; six cerebral events; three cardiac events; and one death. The HD patients group with SCI had none significantly higher cerebral and cardiac morbidity than the group without SCI. Patients with SCI were significantly older than those without SCI and had significantly longer duration of HD. Furthermore, HD patients with SCI had significantly higher systolic and diastolic blood pressure than those without SCI. We could not find a difference between HD patients with SCI and those without SCI as regards other cardiovascular risk factor except for ischemic heart disease [IHD]. Using univariate analysis, we found that age, duration of HD, IHD and silent brain infarction were predictors of vascular events, whereas, duration of HD and SCI were predictors of cerebral events. By multivariate analysis, we found that SCI was a powerful independent predictor of cerebral and vascular events. We concluded that the presence of SCI is an independent risk factor for vascular events in HD patients

Cardiovascular autonomic dysfunction in multiple sclerosis: correlations with clinical, brainstem auditory evoked potential and magnetic resonance imaging

Multiple sclerosis [MS] is one of the most disabling neurological disorders, in which autonomic impairment is not rare. The aim of the current study was to assess the frequency of cardiovascular [CV] autonomic dysfunction in MS patients. We also related these autonomic abnormalities to the brainstem dysfunctions in those patients evidenced by brainstem auditor evoked potential [BAEP] and magnetic resonance imaging [MRI] studies. We studied 20 patients with clinically definite relapsing remitting MS and 20 sex and age matched healthy control. The patients were evaluated clinically using expanded disability status scale [EDSS]. Autonomic functions were evaluated with blood pressure response to both standing and static exercise [sympathetic], and 24-hour electrocardiographic [ECG] recording, time domain [parasympathetic]. Brainstem auditory evoked potential and MRI were performed to all patients. The MS patients included 11 [55%] males and nine [45%] females with a mean age of 29.8 +/- 8.4 years, whereas control group was composed of five [50%] males and five [50%] females with a mean age of 34.2 +/- 13.4 years. Regarding tests of CV autonomic functions, 13 [65%] patients had at least one abnormal test. The results showed statistically significant differences in all CV autonomic tests when comparing MS patients to controls. We found significant correlations between autonomic tests with duration of the disease. Significant correlations were detected between autonomic tests and brainstem lesions as well as periventricular parameters of MRI. BAEP findings were indicative of brainstem affection and there was a significant correlation between autonomic tests and I-V interpeak latency. These results suggest that a significant number of patients with MS show evidence of CV autonomic dysfunction, which is correlated with brainstem function

Early predictors of malignant course of middle cerebral artery infarction: clinical, laboratory and radiological study

Early predictors of deterioration may improve therapeutic decision in patients with acute cerebral ischemia. This study investigated whether measurement of serum protein S100B, beside other clinical and radiological determinants can predict a malignant course of infarction in acute middle cerebral artery [MCA] occlusion. The study included 24 stroke patients admitted within 24 hours after the symptoms onset. In all patients, the stroke was caused by middle cerebral artery infarction as proved by transcranial Doppler [TCD] or computed tomography [CT]. Patients of this study were divided into two groups: group I: included 17 patients with non malignant middle cerebral artery infarction [MCAI]. Group II: included 7 patients with malignant MCAI [mMCAI]. All patients were subjected to complete history taking and thorough neuroglical examination using National Institutes of Health Stroke Scale [NIHSS], brain imaging by computed tomography, transcranial Doppler examination and routine laboratory studies. S100B serum levels were determined in all patients [on admission and 24 hours later] and in 15 age and sex matched control subjects. The functional state of patients was evaluated on discharge by Barthel index [BI] and after 2 months by modified Ranken Scale [MRS]. Patients with mMCAI had significantly higher S100 serum level after 24 hours, and higher NIHSS after 48 hours. These patients had higher incidence of poor outcome both early on discharge [lower BI] and after 2 months [MRS > 3]. On CT examination patients with mMCAI had significantly higher frequency of early hypodensity, large sized infarction, with more severe mass effect. Regarding S100B protein: it could not be detected in any one of the control group. While no significant difference could be found between the two patients' groups on admission, its levels were significantly higher in patients with mMCAI after 24 hours. At that time, levels of S100 were significantly correlated to NIHSS at 48 hours, the infarct volume and the severity of mass effect. Again S100B protein could be correlated to functional outcome of the patients both on discharge and after 2 months. In this study predictors of stroke poor outcome were increased mean age of the patients, presence of diabetes, hypertensions, rapid deterioration in the first 48 hours, and significantly higher S100B after 24 hours from admission. Beside those clinical and laboratory data, neuroradiologic features such as the presence of early hypodenisty, large sized infarction [more than one lobe] and marked mass effect were good predictors of poor functional outcome. Serum S100B concentration 24 to 48 hours after the onset can predict a malignant course of infarction after MCA occlusion and may provide a valuable information for both neurological status and functional impairment on discharge and on long term outcome. Other predictors of the malignant course are early clinical deterioration of the patients, early hypodensity on CT with large sized infarction and severe mass effect. All of these factors beside old age and diabetes can also predict poor outcome after MCAI