The Causative Classification of Stroke system: an international reliability and optimization study.

BACKGROUND: Valid and reliable ischemic stroke subtype determination is crucial for well-powered multicenter studies. The Causative Classification of Stroke System (CCS, available at http://ccs.mgh.harvard.edu) is a computerized, evidence-based algorithm that provides both causative and phenotypic stroke subtypes in a rule-based manner. We determined whether CCS demonstrates high interrater reliability in order to be useful for international multicenter studies. METHODS: Twenty members of the International Stroke Genetics Consortium from 13 centers in 8 countries, who were not involved in the design and development of the CCS, independently assessed the same 50 consecutive patients with acute ischemic stroke through reviews of abstracted case summaries. Agreement among ratings was measured by kappa statistic. RESULTS: The κ value for causative classification was 0.80 (95% confidence interval [CI] 0.78-0.81) for the 5-subtype, 0.79 (95% CI 0.77-0.80) for the 8-subtype, and 0.70 (95% CI 0.69-0.71) for the 16-subtype CCS. Correction of a software-related factor that generated ambiguity improved agreement: κ = 0.81 (95% CI 0.79-0.82) for the 5-subtype, 0.79 (95% CI 0.77-0.80) for the 8-subtype, and 0.79 (95% CI 0.78-0.80) for the 16-subtype CCS. The κ value for phenotypic classification was 0.79 (95% CI 0.77-0.82) for supra-aortic large artery atherosclerosis, 0.95 (95% CI 0.93-0.98) for cardioembolism, 0.88 (95% CI 0.85-0.91) for small artery occlusion, and 0.79 (0.76-0.82) for other uncommon causes. CONCLUSIONS: CCS allows classification of stroke subtypes by multiple investigators with high reliability, supporting its potential for improving stroke classification in multicenter studies and ensuring accurate means of communication among different researchers, institutions, and eras.

Intraventricular hemorrhage: Anatomic relationships and clinical implications.

BACKGROUND: Spontaneous intracerebral hemorrhage (ICH) is frequently associated with intraventricular hemorrhage (IVH), which is an independent predictor of poor outcome. The purpose of this study was to examine the relationship between ICH volume and anatomic location to IVH, and to determine if ICH decompression into the ventricle is truly beneficial. METHODS: We retrospectively analyzed the CT scans and charts of all patients with ICH admitted to our stroke center over a 3-year period. Outcome data were collected using our prospective stroke registry. RESULTS: We identified 406 patients with ICH. A total of 45% had IVH. Thalamic and caudate locations had the highest IVH frequency (69% and 100%). ICH volume and ICH location were predictors of IVH (p < 0.001). Within each location, decompression ranges (specific volume ranges where ventricular rupture tends to occur) were established. Patients with IVH were twice as likely to have a poor outcome (discharge modified Rankin scale of 4 to 6) (OR 2.25, p = 0.001) when compared to patients without IVH. Caudate location was associated with a good outcome despite 100% incidence of IVH. Spontaneous ventricular decompression was not associated with better outcome, regardless of parenchymal volume reduction (p = 0.72). CONCLUSIONS: Intraventricular hemorrhage (IVH) occurs in nearly half of patients with spontaneous intracerebral hemorrhage (ICH) and is related to ICH volume and location. IVH is likely to occur within the "decompression ranges" that take into account both ICH location and volume. Further, spontaneous ventricular decompression does not translate to better clinical outcome. This information may prove useful for future ICH trials, and to the clinician communicating with patients and families.

Chemokine receptors expressed on T cells in packed red blood cell units change over storage time.

The transfusion of blood products is associated with adverse events that are related to the leukocytes in stored units of blood. These leukocytes have been shown to promote the elaboration of inflammatory cytokines. However, the status of a set of key inflammatory mediators, chemokine receptors, expressed on T lymphocytes in stored red blood cell (RBC) units is largely unknown. We investigated the expression pattern of selected chemokine receptors on T cells from non-leukocyte-reduced RBC units over storage time. Selecting segments from stored RBC units, we evaluated the T-cell subsets for the chemokine receptors CXCR3 and CCR4 by flow cytometry. Statistical analysis was performed by regression analysis. We analysed 30 samples stored between 5 and 38 days. The CD4+ T cells expressing CXCR3 increased by 0.27% daily (P= 0.02), whereas the expression of CCR4 declined by 0.40% daily (P < 0.001). Though the expression of the chemokine receptors on CD8+ cells followed the same trend, the changes were statistically nonsignificant. This study suggests that a longer duration of storage is associated with a higher expression of chemokine receptor CXCR3 and a lower expression of CCR4 on T cells in RBC units, suggesting a pro-inflammatory Th1 bias. The clinical significance of these changes in the setting of adverse transfusion events needs further evaluation.