Human TUBB3 mutations perturb microtubule dynamics, kinesin interactions, and axon guidance.

We report that eight heterozygous missense mutations in TUBB3, encoding the neuron-specific beta-tubulin isotype III, result in a spectrum of human nervous system disorders that we now call the TUBB3 syndromes. Each mutation causes the ocular motility disorder CFEOM3, whereas some also result in intellectual and behavioral impairments, facial paralysis, and/or later-onset axonal sensorimotor polyneuropathy. Neuroimaging reveals a spectrum of abnormalities including hypoplasia of oculomotor nerves and dysgenesis of the corpus callosum, anterior commissure, and corticospinal tracts. A knock-in disease mouse model reveals axon guidance defects without evidence of cortical cell migration abnormalities. We show that the disease-associated mutations can impair tubulin heterodimer formation in vitro, although folded mutant heterodimers can still polymerize into microtubules. Modeling each mutation in yeast tubulin demonstrates that all alter dynamic instability whereas a subset disrupts the interaction of microtubules with kinesin motors. These findings demonstrate that normal TUBB3 is required for axon guidance and maintenance in mammals.

Predicting Failure to Recover Swallowing in Patients with Severe Post-stroke Dysphagia: The DIsPHAGIc Score.

In post-stroke dysphagia, early identification of patients at highest risk of failing swallowing recovery (SR) would be useful to decide which of them should undergo percutaneous endoscopic gastrostomy. The studies on this subject were numerous but generally based on small statistical samples. In this retrospective study, 1232 patients with ischemic or hemorrhagic stroke (73.7 ± 13.0 years, 51% men) were assessed: 593 non-dysphagic, 351 partially dysphagic and 288 totally dysphagic. Among the latter, 45.1% could not recover oral intake. A score to assess the risk of failing SR was obtained from the group with total dysphagia, and further 210 patients with total post-stroke dysphagia were utilized for validation. A regular progression of stroke severity markers, complications and mortality was observed from non-dysphagic, to partially dysphagic, up to totally dysphagic patients. Among the latter, seven variables were independently associated with failure of SR, and formed the "DIsPHAGIc score": cerebral lesion Diameter ≥ 6 cm (+ 1), left frontal Ischemia (- 1), Partial anterior circulation syndrome (- 1), Hypoxia (+ 1), Antiplatelet drug (+ 1), GCS verbal reaction < 4 (+ 1), Internal capsule ischemia (- 1). The area under the ROC curve was 0.79 (95% CI 0.74-0.85). For total scores ≥ 2 there was a high risk of failing SR, with specificity 76.9%, sensitivity 72.1% and accuracy 74.7%. The application of the DIsPHAGIc score to the validation sample provided almost identical results. The evolution of post-stroke dysphagia towards irreversibility can be predicted by a simple, reproducible and robust scoring system based on 7 variables commonly available during hospitalization.

Association of Left Ventricular Hypertrophy and Atrial Fibrillation with Hemorrhagic Evolution of Small Vessel Disease.

OBJECTIVES: Cerebral small vessel disease (SVD) is often associated with hypertension and may evolve towards intracerebral hemorrhage (ICH) or lacunar ischemic stroke. However, the factors favoring the evolution towards ICH or lacunar stroke are not well understood. MATERIALS AND METHODS: This retrospective study included 326 consecutive patients (71.1±13.2 years, 38% women): 143 with deep ICH and 183 with lacunar lesions (LL) <2 cm, which were visible in a deep location on brain CT scan. Among LL patients, 143 had a small-artery occlusion (SAO) stroke according to the TOAST classification. Clinical characteristics plus laboratory and neuroradiological variables of these patients had been prospectively collected and a subgroup underwent echocardiography. RESULTS: In multivariate analysis, ICH patients (97% hypertensive), compared to SAO patients (89% hypertensive), had greater left ventricular wall thickness (LVWT; OR 4.15, 95%CI 1.64-10.53, for those with LVWT ≥ 1.4 cm, 70% of whom were hemorrhagic) and lower prevalence of white matter lesions (OR 0.30, 95%CI 0.13-0.70), ever smokers (OR 0.39, 95%CI 0.18-0.82) and diabetics (OR 0.29, 95% CI 0.10-0.84). Moreover, ICH patients had a greater prevalence of atrial fibrillation than LL patients (OR 3.14, 95%CI 1.11-8.93), and so they were more often anticoagulated. CONCLUSIONS: Most SVD patients were hypertensive, but those evolving towards ICH were characterized by organ damage at the cardiac level (increase in LVWT and atrial fibrillation), while those evolving towards lacunar stroke were characterized by a higher prevalence of smokers and diabetics, and by organ damage at the cerebral level (white matter lesions).

Usefulness of the ACTEL Score to Predict Atrial Fibrillation in Patients with Cryptogenic Stroke.

INTRODUCTION: To assess the probability of undetected atrial fibrillation (AF) in patients with ischemic stroke, we previously compared patients who were first diagnosed with AF with patients with large or small artery disease and obtained the MrWALLETS 8-item scoring system. In the present study, we utilized cryptogenic strokes (CS) as the control group, as AF is normally sought among CS patients. METHODS: We retrospectively examined 191 ischemic stroke patients (72.5 ± 12.6 years), 68 with first diagnosed AF and 123 with CS, who had undergone 2 brain CT scans, echocardiography, carotid/vertebral ultrasound, continuous electrocardiogram monitoring and anamnestic/laboratory search for cardiovascular risk factors. RESULTS: In logistic regression, 5 variables were independently associated with AF, forming the "ACTEL" score: Age ≥75 years (OR 2.42, 95% CI 1.18-4.96, p = 0.02; +1 point); hyperCholesterolemia (OR 0.38, 95% CI 0.18-0.78, p = 0.009; -1 point); Tricuspid regurgitation ≥ mild-to-moderate (OR 4.99, 95% CI 1.63-15.27, p = 0.005; +1 point); left ventricular End-diastolic volume <65 mL (OR 7.43, 95% CI 2.44-22.6, p = 0.0004; +1 point); Left atrium ≥4 cm (OR 4.57, 95% CI 1.97-10.62, p = 0.0004; +1 point). The algebraic sum of these points may range from -1 to +4. For AF identification, the area under the receiver operating characteristic curve was 0.80 (95% CI 0.73-0.87). With a cutoff of ≥2, positive predictive value was 80.8%, specificity 92.7% and sensitivity 55.9%. CONCLUSIONS: The ACTEL score, a simplified and improved version of the MrWALLETS score, allows the identification of patients with first diagnosed AF, in the context of CSs, with a high positive predictive value.

Venous thromboembolism prevention with low molecular weight heparin may reduce hemorrhagic transformation in acute ischemic stroke.

BACKGROUND: Subcutaneous heparin at a prophylactic dose (SHPD) is a rather common treatment in ischemic stroke, but whether it confers an increased risk of hemorrhagic transformation of cerebral infarct (HT) and whether its reduction or discontinuation favors HT regression are presently poorly understood. METHODS: Two samples of ischemic stroke patients with a cerebral lesion diameter ≥ 3 cm on brain CT scan, admitted over 7 years to our stroke unit, were retrospectively examined: (1) patients treated or not treated with SHPD (enoxaparin 4000 U/day), with subsequent assessment of possible HT appearance (N = 267, mean age 75.9 ± 12.8 years) and (2) patients treated with SHPD, with HT and subsequent reduction/discontinuation or maintenance of the initial dose, and subsequent assessment of HT evolution (N = 116, mean age 75.7 ± 11.1 years). HT severity was quantified according to the ECASS study (HT score). RESULTS: In the first sample, after adjustment for age, sex, stroke severity, cerebral lesion diameter, and other possible confounders, SHPD was inversely associated with HT appearance (hazard ratio 0.62, 95% CI 0.39-0.98, P = 0.04). In the second sample, after adjustment for age, sex, stroke severity, cerebral lesion diameter, and initial HT severity, SHPD reduction/discontinuation had an inverse effect on both HT score improvement (odds ratio 0.42, 95% CI 0.18-0.99, P = 0.049) and HT improvement according to neuroradiological reports (odds ratio 0.34, 95% CI 0.14-0.82, P = 0.015). CONCLUSIONS: This retrospective study suggests that SHPD may play a protective role in HT appearance and evolution, which requires verification by a randomized clinical trial.

Short- and Long-Term Stroke Risk after Urgent Management of Transient Ischaemic Attack: The Bologna TIA Clinical Pathway.

BACKGROUND: Rapid management can reduce the short stroke risk after transient ischaemic attack (TIA), but the long-term effect is still little known. We evaluated 3-year vascular outcomes in patients with TIA after urgent care. METHODS: We prospectively enrolled all consecutive patients with TIA diagnosed by a vascular neurologist and referred to our emergency department (ED). Expedited assessment and best secondary prevention was within 24 h. Endpoints were stroke within 90 days, and stroke, myocardial infarction, and vascular death at 12, 24 and 36 months. RESULTS: Between August 2010 and July 2013, we evaluated 686 patients with suspected TIA; 433 (63%) patients had confirmed TIA. Stroke at 90 days was 2.07% (95% confidence interval (CI), 1.1-3.9) compared with the ABCD2-predicted risk of 9.1%. The long-term stroke risk was 2.6% (95% CI, 1.1-4.2), 3.7% (95% CI, 1.6-5.9) and 4.4% (95% CI, 1.9-6.8) at 12, 24 and 36 months, respectively. The composite outcome of stroke, myocardial infarction, and vascular death was 3.5% (95% CI, 1.7-5.1), 4.9% (95% CI, 2.5-7.4), and 5.6% (95% CI, 2.8-8.3) at 12, 24, and 36 months, respectively. CONCLUSIONS: TIA expedited management driven by vascular neurologists was associated with a marked reduction in the expected early stroke risk and low long-term risk of stroke and other vascular events.

Bilateral orbital Erdheim-Chester disease treated with 12 weekly administrations of VNCOP-B chemotherapy: a case report and a review of literature.

Erdheim-Chester disease (ECD) is a non-Langerhans' cells histiocytosis of unknown etiology, which generally presents with long bones involvement, even if extraskeletal lesions may be frequently recognized. As a consequence of its rarity, there is no consensus concerning the best standard of care for affected patients. We present the case of a 53-year-old woman with bilateral orbital histologically documented ECD, presenting with an important thickening and swelling of the periorbital tissue and massive involvement of lateral rectal muscles, as documented by magnetic resonance. The patient was successfully addressed to 12 cycles of a weekly lymphoma-designed chemotherapy regimen, including etoposide, mitoxantrone, cyclophosphamide, vincristine, bleomycin, and prednisone (VNCOP-B regimen). Periorbital lesions reduced during the courses of chemotherapy, along with a regression to normal appearance of the extrinsic ocular musculature. This appears as an effective and well-tolerated first-line treatment option for ECD patients, due to the possibility of maintaining an adequate dose intensity, with also a concomitant continuous steroid administration.

Prognostic significance of diabetes and stress hyperglycemia in acute stroke patients.

BACKGROUND: Hyperglycemic non-diabetic stroke patients have a worse prognosis than both normoglycemic and diabetic patients. Aim of this study was to assess whether hyperglycemia is an aggravating factor or just an epiphenomenon of most severe strokes. METHODS: In this retrospective study, 1219 ischemic or hemorrhagic stroke patients (73.7 ± 13.1 years) were divided into 4 groups: 0 = non-hyperglycemic non-diabetic, 1 = hyperglycemic non-diabetic, 2 = non-hyperglycemic diabetic and 3 = hyperglycemic diabetic. Hyperglycemia was defined as fasting blood glucose ≥ 126 mg/dl (≥ 7 mmol/l) measured the morning after admission, while the diagnosis of diabetes was based on a history of diabetes mellitus or on a glycated hemoglobin ≥ 6.5% (≥ 48 mmol/mol), independently of blood glucose levels. All diabetic patients, except 3, had Type 2 diabetes. The 4 groups were compared according to clinical history, stroke severity indicators, acute phase markers and main short term stroke outcomes (modified Rankin scale ≥ 3, death, cerebral edema, hemorrhagic transformation of ischemic lesions, fever, oxygen administration, pneumonia, sepsis, urinary infection and heart failure). RESULTS: Group 1 patients had more severe strokes, with larger cerebral lesions and higher inflammatory markers, compared to the other groups. They also had a high prevalence of atrial fibrillation, prediabetes, previous stroke and previous arterial revascularizations. In this group, the highest frequencies of cerebral edema, hemorrhagic transformation, pneumonia and oxygen administration were obtained. The prevalence of dependency at discharge and in-hospital mortality were equally high in Group 1 and Group 3. However, in multivariate analyses including stroke severity, cerebral lesion diameter, leukocytes and C-reactive protein, Group 1 was only independently associated with hemorrhagic transformation (OR 2.01, 95% CI 0.99-4.07), while Group 3 was independently associated with mortality (OR 2.19, 95% CI 1.32-3.64) and disability (OR 1.70, 95% CI 1.01-2.88). CONCLUSIONS: Hyperglycemic non-diabetic stroke patients had a worse prognosis than non-hyperglycemic or diabetic patients, but this group was not independently associated with mortality or disability when size, severity and inflammatory component of the stroke were accounted for.

Predicting hemorrhagic transformation and its timing from maximum cerebral lesion diameter in nonlacunar ischemic strokes.

OBJECTIVES: We performed this retrospective cohort study to establish which factors are mostly indicative of the appearance of hemorrhagic transformation (HT) and of its time course in a sample of nonlacunar ischemic strokes. MATERIALS AND METHODS: In 402 patients with nonlacunar ischemic stroke (75.0 ± 12.7 years, 192 male), clinical, laboratory, and neuroimaging variables obtained during the first 3 days of hospitalization were compared between patients with and without HT at computer tomography scan. RESULTS: HT was documented in 129 patients (32.1%), including 36 with parenchymal hematoma (PH), after a median time of 6 days (range 1-27). Many variables were univariately associated with HT, but only 5 of them were confirmed in Cox regression (Hazard Ratio, 95% Confidence Interval): maximum cerebral lesion diameter (CLD) in cm (1.12, 1.06-1.18; p = .0001), hemoglobin in g/dl (1.16, 1.06-1.27; p = .002), blood glucose in mmol/L (1.10, 1.03-1.18; p = .007), prior anticoagulant therapy (1.82, 1.10-3.03; p = .02), and edema with mass effect (1.72, 1.08-2.75; p = .02). Thus, the most significant predictor was CLD. The overall risk of HT was minimum for CLD < 2 cm (1.5%), intermediate for CLD ≥ 2 and < 5 cm (22%), and maximum for CLD ≥ 5 cm (58%). The residual probability of having HT decreased progressively over time, and a simple formula is proposed to predict, from CLD in cm, when the probability of HT falls below 10%. CONCLUSIONS: The main determinant of HT was CLD, a simple quantitative parameter that could prove useful, in particular, in deciding the timing of anticoagulation in cardioembolic stroke patients.

Acquired intracranial arterial aneurysm and stroke after vessel dissection in a child with coarctation of the aorta.

Vascular events in patients with coarctation of the aorta have been extensively reported and account for the majority of morbidity and mortality in untreated patients. The exact mechanism for this association is not completely understood and may include acquired anomalies or congenital abnormalities of intracranial vessel. Here we report a case of intracranial internal carotid artery dissection with subsequent formation of acquired large carotid aneurysm in a child with severe systemic hypertension and coarctation of the aorta. Endovascular aneurysm exclusion was pursued and it was able to control this potentially lethal complication. This case supports the notion of acquired nature of intracranial vessel abnormalities and underscores the clinical role of interventional neuroradiology in a subset of patients with congenital heart disease.