Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common form of hereditary stroke disorder caused by mutations in the NOTCH3 gene. Although CADASIL scale is a widely used tool to screen clinically suspected CADASIL patients, the differential effects of this scale in various populations remain unknown.
92 CADASIL-like patients and 24 CADASIL patients were selected based on CADASIL scale and gene tests. The clinical, genetic and radiological characteristics were analyzed.
Based on the CADASIL scale, we first screened 116 suspected CADASIL patients, and detected 20 mutations in 24 CADASIL-patients (Specificity: 20.69 %). Surprisingly, we found that transient ischemic attack/stroke, migraine, cognitive decline, psychiatric disturbances and early onset age in CADASIL scale showed no differences between the CADASIL and the CADASIL-like patients (p > 0.05). Instead, recurrent cerebral ischemic events (58.33 %, p = 0.028) and positive family histories (p < 0.05) were more frequently observed in CADASIL patients. Moreover, compared with CADASIL-like patients (21.74 %), CADASIL patients demonstrated higher percentage of temporal pole involvements (58.33 %, p = 0.001), but not the external capsule involvements (66.67 %, p = 0.602), in MRI imaging. Further, we found that vascular risk factors could occur in both CADASIL patients and CADASIL-like patients, and therefore could not be used as the markers to differentiate the two groups in our study (p > 0.05). By performing DSA analysis, we for the first time identified dysplasia of cerebral blood vessels in CADASIL patients, which were detected more frequently in CADASIL patients (41.67 %) in comparison with CADASIL-like patients (8.69 %, p <0.01).
Our data suggested that the efficacy of CADASIL scale to diagnose the disease varied with specific populations. Recurrent cerebral ischemic events, temporal pole involvements (but not the external capsule) in MRI imaging and dysplasia of cerebral blood vessels in DSA may be the new potential risk factors of the CADASIL scale suitable for Chinese patients. Gene testing by encephalopathy gene panel is expected to improve the accuracy of CADASIL differential diagnosis and increase the understanding of this disease in the future.
CADASIL; Small vessel disease; Phenotype; Genotype; CADASIL scale
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an autosomal dominant angiopathy caused by a mutation in the notch 3 gene on chromosome 19. Clinically, patients may be asymptomatic or can present with recurrent ischemic episodes and strokes leading to dementia, depression, pseudobulbar palsy, and hemi- or quadraplegia. Additional manifestations that have been described include migraine (mostly with aura), psychiatric disturbances, and epileptic seizures. Neuroimaging is essential to the diagnosis of CADASIL. On imaging CADASIL is characterized by symmetric involvement by confluent lesions located subcortically in the frontal and temporal lobes as well as in the insula, periventricularly, in the centrum semiovale, in the internal and external capsule, basal ganglia, and brain stem; with relative sparing of the fronto-orbital and the occipital subcortical regions. We describe a 49 year old male with CADASIL with absence of temporal lobe findings on MRI but predominant lesions within the periventricular white matter, occipital lobes with extension into the subcortical frontal lobes, corpus callosum and cerebellar white matter. Although CADASIL characteristically presents with anterior temporal lobe involvement, these findings may be absent and our case addresses the atypical imaging findings in CADASIL.
Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL); dementia; migraine; magnetic resonance imaging (MRI); occipital lobe; seizures
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited cerebrovascular disease, clinically characterized by variable manifestations of migraine, recurrent transient ischemic attack or lacunar strokes, cognitive decline, and mood disturbances. However, manic episodes have rarely been documented as an initial symptom of CADASIL and bipolar disorder presenting as the first manifestation in CADASIL has not been reported previously from evaluations by psychiatrists or psychological testing by psychologists.
A 53 year old woman developed symptoms of mania in her 50s leading to a personality change involving a continuously labile mood and irritability over a number of years. Neuropsychological testing revealed an intact memory, but impairment in attention and executive function. In the Rorschach test, she showed a high level of cognitive rigidity. Magnetic resonance imaging findings were very consistent with a diagnosis of CADASIL, which was confirmed by genetic testing for NOTCH3 mutations. Atypical antipsychotics proved to be helpful in treating her manic symptoms and for behavior control.
We present a novel case of CADASIL that first presented as bipolar disorder. We contend that when patients show a late onset personality change or chronically irritable mood that deteriorates over many years, an organic cause such as CADASIL must be considered. Further studies are needed to better understand the exact impacts of cerebral tissue lesions and psychiatric symptoms in CADASIL patients.
CADASIL; Bipolar disorder; Mood disorder; NOTCH3
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) often presents with a history of migraine with aura and eventual manifestations of dementia with unrelenting, repeated cerebral vascular insults. Only 6–10% of patients with CADASIL have been reported to develop seizures, and status epilepticus (SE) is exceedingly rare. Here, we describe a patient who presented with recurrent SE, with eventual biopsy diagnosis of CADASIL.
An 80-year-old woman presented to our hospital three times in two years with decreased level of consciousness and subtle intermittent right-sided upper extremity and facial twitching. There was no known significant family history and no past medical history for seizures, stroke, migraine headache, or overt dementia. Electroencephalography revealed recurrent focal seizures with left hemispheric onset and evolution, fulfilling the criteria for focal SE each time. All three admissions required sedation with midazolam to control seizure activity, in addition to high doses of multiple antiepileptic drugs. Brain MRI repeatedly showed extensive abnormalities in the periventricular and deep white matter, subcortical white matter, and bilateral basal ganglia. Skin biopsy was obtained on the third admission, and electron microscopy showed numerous deposits of granular osmiophilic material, which are pathognomonic for CADASIL. Detailed investigations failed to reveal any other etiology for the patient's condition.
This case illustrates the potential for nonconvulsive SE to be the sole manifestation of CADASIL. With the appropriate brain MRI findings, CADASIL should be added to the list of rare causes of SE.
CADASIL, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy; SE, status epilepticus; CSF, cerebrospinal fluid; PEG, percutaneous endoscopic gastrostomy; CADASIL; Status epilepticus; Seizures; EEG; MRI
Background and Purpose
Although cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common single-gene disorder of cerebral small blood vessels caused by NOTCH3 mutations, little has been described about the variation in the clinical findings between its underlying types of mutations. In particular, the presence of cerebral microbleeds (CMBs) has been an increasingly recognized magnetic resonance imaging finding in CADASIL, but their clinical significance is not clear. The purpose of this study is to assess whether CMBs are associated with symptomatic stroke in the CADASIL patients with R544C mutation and to compare the cerebral distribution of CMBs between CADASIL patients with and without symptomatic stroke.
This is a cohort study of patients who were diagnosed with genotype-confirmed R544C-mutation CADASIL. Primary neurologic symptoms were recorded. Symptomatic strokes were defined as transient ischemic attack, ischemic strokes and hemorrhagic strokes. CMBs were defined as focal areas of round signal loss on T2*-weighted gradient echo planar images with a diameter of less than 10 mm. The locations of CMBs were divided into lobar, basal ganglia, thalamus, brain stem and cerebellum. Multiple logistic regressions were performed to identify the epidemiologic or vascular risk factors associated with symptomatic stroke in patients with CADASIL.
Among total of 51 subjects in this cohort, CMBs were present in 20 of 32 patients (64.5%) in the symptomatic stroke-group and in 8 of 19 patients (42.1%) in the non-stroke group (p = 0.16). CMBs were observed more frequently in the basal ganglia (p<0.001) and the cerebellum (p<0.018) in the symptomatic stoke group compared to the non-stroke group. The mean number of CMBs was significantly higher in the symptomatic stroke group (15.4±18.0 lesions per patients with CMBs) versus those without symptomatic stroke (3.3±3.0 lesions per patients with CMBs) (p = 0.003). Hypertension was an independent risk factor for symptomatic stroke in CADASIL (p = 0.014). It was independently associated with CMBs locations as basal ganglia (p = 0.016), thalamus (p = 0.010), brainstem (p = 0.044), and cerebellum (p = 0.049). However, It was not independently associated with CMBs on lobar lesion (p = 0.152).
In this study hypertension was an independent predictor of CMBs presence in specific brain locations, as well as symptomatic stroke in the CADASIL patients. The distribution and burden of CMBs might be a clinically useful marker for the risk of symptomatic stroke. However, further prospective studies on the relationship between CMBs distribution and symptomatic stroke are required in order to support these preliminary findings.
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy (CADASIL) is one of the most common heritable causes of stroke and dementia in adults. The gene involved in the pathogenesis of CADASIL is Notch3; in which mutations affect the number of cysteine residues in its extracellular domain, causing its accumulation in small arteries and arterioles of the affected individuals. Besides the usual neurological and vascular findings that have been well-documented in CADASIL patients, this paper additionally reports multiple neoplastic lesions that were observed in an autopsy case of CADASIL patient; that could be related to Notch3 mutation. The patient was a 62 years old male, presented with a past history of neurological manifestations, including gait disturbance and frequent convulsive attacks. He was diagnosed as CADASIL syndrome with Notch3 Arg133Cys mutation. He eventually developed hemiplegia and died of systemic convulsions. Autopsy examination revealed-besides the vascular and neurological lesions characteristic of CADASIL- multiple neoplastic lesions in the body; carcinoid tumorlet and diffuse idiopathic pulmonary neuro-endocrine cell hyperplasia (DIPNECH) in the lungs, renal cell carcinoma (RCC), prostatic adenocarcinoma (ADC) and adenomatoid tumor of the epididymis. This report describes a spectrum of neoplastic lesions that were found in a case of CADASIL patient that could be related to Notch3 gene mutations.
Cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy; autopsy case; neoplastic lesions
Introduction: CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy), the most common inherited cause of stroke and dementia in adults, has been described in six Greek families. Common presenting manifestations include migraine with aura, brain ischemia, mood disorders and cognitive decline. Spontaneous intracerebral hemorrhage (SICH) rarely occurs in CADASIL and only exceptionally as the first clinical manifestation.
Case description: We have previously reported the sixth Greek family with CADASIL and in particular, two brothers in whom the genetic testing documented a classic mutation of the NOTCH3 gene (Arg169Cys). In this report, we describe the 30-year-old son of the second brother, who suffered a thalamic SICH as the presenting manifestation of CADASIL, in the absence of arterial hypertension or antiplatelet drug use.
Conclusion: Patients with acute subcortical infarcts, leukoencephalopathy, a history of migraine, mood disorders, and dementia, should always raise the suspicion of CADASIL. However, a SICH, even in the absence of classical risk factors for hemorrhage, is possible and should not exclude the diagnosis of CADACIL. Hippokratia 2016, 20(1): 76-79
CADASIL; NOTCH3 gene; intracerebral hemorrhage
To determine the frequency of distinctive EGFr cysteine altering NOTCH3 mutations in the 60,706 exomes of the exome aggregation consortium (ExAC) database.
ExAC was queried for mutations distinctive for cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), namely mutations leading to a cysteine amino acid change in one of the 34 EGFr domains of NOTCH3. The genotype‐phenotype correlation predicted by the ExAC data was tested in an independent cohort of Dutch CADASIL patients using quantified MRI lesions. The Dutch CADASIL registry was probed for paucisymptomatic individuals older than 70 years.
We identified 206 EGFr cysteine altering NOTCH3 mutations in ExAC, with a total prevalence of 3.4/1000. More than half of the distinct mutations have been previously reported in CADASIL patients. Despite the clear overlap, the mutation distribution in ExAC differs from that in reported CADASIL patients, as mutations in ExAC are predominantly located outside of EGFr domains 1–6. In an independent Dutch CADASIL cohort, we found that patients with a mutation in EGFr domains 7–34 have a significantly lower MRI lesion load than patients with a mutation in EGFr domains 1–6.
The frequency of EGFr cysteine altering NOTCH3 mutations is 100‐fold higher than expected based on estimates of CADASIL prevalence. This challenges the current CADASIL disease paradigm, and suggests that certain mutations may more frequently cause a much milder phenotype, which may even go clinically unrecognized. Our data suggest that individuals with a mutation located in EGFr domains 1–6 are predisposed to the more severe “classical” CADASIL phenotype, whereas individuals with a mutation outside of EGFr domains 1–6 can remain paucisymptomatic well into their eighth decade.
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare hereditary stroke caused by mutations in NOTCH3 gene. We report the first case of CADASIL in an indigenous Rungus (Kadazan-Dusun) family in Kudat, Sabah, Malaysia confirmed by a R54C (c.160C>T, p.Arg54Cys) mutation in the NOTCH3. This mutation was previously reported in a Caucasian and two Korean cases of CADASIL. We recruited two generations of the affected Rungus family (n = 9) and found a missense mutation (c.160C>T) in exon 2 of NOTCH3 in three siblings. Two of the three siblings had severe white matter abnormalities in their brain MRI (Scheltens score 33 and 50 respectively), one of whom had a young stroke at the age of 38. The remaining sibling, however, did not show any clinical features of CADASIL and had only minimal changes in her brain MRI (Scheltens score 17). This further emphasized the phenotype variability among family members with the same mutation in CADASIL. This is the first reported family with CADASIL in Rungus subtribe of Kadazan-Dusun ethnicity with a known mutation at exon 2 of NOTCH3. The penetrance of this mutation was not complete during the course of this study.
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, or CADASIL, one of the most common inherited small vessel diseases of the brain, is characterized by a progressive loss of vascular smooth muscle cells and extracellular matrix accumulation. The disease is caused by highly stereotyped mutations within the extracellular domain of the NOTCH3 receptor (Notch3ECD) that result in an odd number of cysteine residues. While CADASIL-associated NOTCH3 mutations differentially affect NOTCH3 receptor function and activity, they all are associated with early accumulation of Notch3ECD-containing aggregates in small vessels. We still lack mechanistic explanation to link NOTCH3 mutations with small vessel pathology. Herein, we hypothesized that excess Notch3ECD could recruit and sequester functionally important proteins within small vessels of the brain. We performed biochemical, nano-liquid chromatography-tandem mass spectrometry and immunohistochemical analyses, using cerebral and arterial tissue derived from patients with CADASIL and mouse models of CADASIL that exhibit vascular lesions in the end- and early-stage of the disease, respectively. Biochemical fractionation of brain and artery samples demonstrated that mutant Notch3ECD accumulates in disulphide cross-linked detergent-insoluble aggregates in mice and patients with CADASIL. Further proteomic and immunohistochemical analyses identified two functionally important extracellular matrix proteins, tissue inhibitor of metalloproteinases 3 (TIMP3) and vitronectin (VTN) that are sequestered into Notch3ECD-containing aggregates. Using cultured cells, we show that increased levels or aggregation of Notch3 enhances the formation of Notch3ECD–TIMP3 complex, promoting TIMP3 recruitment and accumulation. In turn, TIMP3 promotes complex formation including NOTCH3 and VTN. In vivo, brain vessels from mice and patients with CADASIL exhibit elevated levels of both insoluble cross-linked and soluble TIMP3 species. Moreover, reverse zymography assays show a significant elevation of TIMP3 activity in the brain vessels from mice and patients with CADASIL. Collectively, our findings lend support to a Notch3ECD cascade hypothesis in CADASIL disease pathology, which posits that aggregation/accumulation of Notch3ECD in the brain vessels is a central event, promoting the abnormal recruitment of functionally important extracellular matrix proteins that may ultimately cause multifactorial toxicity. Specifically, our results suggest a dysregulation of TIMP3 activity, which could contribute to mutant Notch3ECD toxicity by impairing extracellular matrix homeostasis in small vessels.
CADASIL; Notch3; protein aggregation; extracellular matrix proteins; cerebrovasculature
Cerebral autosomal dominant arteriopathy with
subcortical infarcts and leukoencephalopathy (CADASIL) is a rare
inherited adult onset disease characterised most commonly by cerebral
ischaemic events and dementia. It is caused by mutations in the
Notch3 gene with most
clustering in exons 3 and 4. Whether these mutations have any influence
on common sporadic ischaemic stroke or dementia cases has not been
investigated, partly hampered by the lack of a readily usable genetic test.
An easy to use diagnostic array for CADASIL
was designed using various restriction endonucleases for the known
mutations in exons 3 and 4 and novel mismatch primers were designed
where no such enzymes existed. This array was used to identify the
allele frequencies of CADASIL mutations and polymorphisms in selected disease cohorts. Seventy patients with radiologically established sporadic ischaemic stroke and 77 patients from a specialist young dementia clinic were recruited. One hundred and seventeen age and sex
matched asymptomatic controls were also identified.
The diagnostic array was found to work well. None of the 14 known mutations and three previously identified polymorphisms (C474A,
A587G, and C594A) in exons 3 and 4 were present in 140stroke, 110 dementia, or 234 control chromosomes. Molecular variant C381T occurred
with a higher frequency of 0.13, whereas G684A occurred with a lower
frequency (0.09) than previously reported, although there were no
statistical differences between selected cohorts.
conclusion, a readily usable
genetic test for CADASIL has been devised that was used to determine
allele frequencies in well characterised cohorts of sporadic stroke and
dementia patients. The data suggest that despite the clinical
resemblance, CADASIL is not a common masquerading cause of stroke or
dementia. The test will enable units locally to rapidly screen patients
with suspected CADASIL.
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an adult onset cerebral small vessel disorder caused by the mutations of the neurogenic locus notch homolog protein 3 (NOTCH3) gene. The extracellular part of NOTCH3 is composed of 34 epidermal growth factor-like (EGF-like) repeat domains. Each EGF-like domain is rich of cysteine and glycine to produce three loops that are essential for high-affinity binding to its ligand. Nearly all reported CADASIL-associated mutations result in gain or loss of a cysteine residue within the EGF-like domains. Only a few cysteine-sparing NOTCH3 mutations have been documented in the patients with CADASIL to date. Here, we reported a Chinese CADASIL family with a cysteine-sparing NOTCH3 mutation. In this family, affected patients had dizziness, memory loss, gait instability, or hemiplegia. Brain magnetic resonance imaging (MRI) showed diffuse leukoencephalopathy with confluent signal abnormalities in the periventricular white matter, basal ganglia, and centrum semiovale bilaterally. By screening the entire coding region of NOTCH3, a novel missense mutation p.G149V (c.446G>T) was found. This mutation was not detected in 400 normal controls. Considering the critical position of glycine within the C-loop of EGF-like domain and its high conservation through evolution, p.G149V mutation could be a potential pathogenic cause for CADASIL.
We report a patient with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), who showed injuries of the neural tracts, which was demonstrated by diffusion tensor tractography (DTT).
A 64-year-old male patient and seven age-matched control volunteers were recruited. Since approximately 1.5 years ago, he had felt mild weakness of the right arm and was diagnosed as CADASIL by the finding of the exon 11 mutation of the NOTCH3 gene approximately 10 months ago. T2-weighted and FLAIR brain MRI images obtained at admission showed high signal intensity lesions in the subcortical gray matter and periventricular white matter. He showed mild quadriparesis, mild dysarthria, mild cognitive impairment, and emotional problems. Diffusion tensor imaging was performed and nine neural tracts (corticospinal tract, corticobulbar tract, corticofugal tract from the supplementary motor area, corticofugal tract from the premotor cortex, thalmoprefrontal tract [TPT] to the dorsolateral prefrontal cortex, TPT to the ventrolateral prefrontal cortex, TPT to the orbitoprefrontal cortex, fornix, and cingulum) were reconstructed. Fractional anisotropy (FA), mean diffusivity (MD), and tract volume of each neural tract were measured. All neural tracts except for the left fornix showed at least one more abnormality in terms of DTT parameters (decrement of FA, increment of MD, or decrement of tract volume).
We demonstrated injuries of the neural tracts in a patient with CADASIL. It appears that clinical manifestations in this patient were related to injuries of the neural tracts.
CADASIL; Diffusion tensor imaging; Diffusion tensor tractography
The Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) affects mainly small cerebral arteries and leads to disability and dementia. The relationship between clinical expression of the disease and progression of the microvessel pathology is, however, uncertain as we lack tools for imaging brain vessels in vivo. Ophthalmoscopy is regarded as a window into the cerebral microcirculation. In this study we carried out an ophthalmoscopic examination in subjects with CADASIL. Specifically, we performed fractal analysis of digital retinal photographs. Data are expressed as mean fractal dimension (mean-D), a parameter that reflects complexity of the retinal vessel branching. Ten subjects with genetically confirmed diagnosis of CADASIL and 10 sex and age-matched control subjects were enrolled. Fractal analysis of retinal digital images was performed by means of a computer-based program, and the data expressed as mean-D. Brain MRI lesion volume in FLAIR and T1-weighted images was assessed using MIPAV software. Paired t-test was used to disclose differences in mean-D between CADASIL and control groups. Spearman rank analysis was performed to evaluate potential associations between mean-D values and both disease duration and disease severity, the latter expressed as brain MRI lesion volumes, in the subjects with CADASIL. The results showed that mean-D value of patients (1.42±0.05; mean±SD) was lower than control (1.50±0.04; p = 0.002). Mean-D did not correlate with disease duration nor with MRI lesion volumes of the subjects with CADASIL. The findings suggest that fractal analysis is a sensitive tool to assess changes of retinal vessel branching, likely reflecting early brain microvessel alterations, in CADASIL patients.
Background and Purpose
White matter (WM) hyperintensities upon magnetic resonance imaging (MRI) or leukoaraiosis is characteristic of stroke syndromes. Increased MRI signals in the anterior temporal pole are suggested to be diagnostic for cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), with 90% sensitivity and 100% specificity. The structural correlates of these specific WM hyperintensities seen on T2-weighted and FLAIR sequences in the temporal pole of CADASIL are unclear. We assessed pathological changes in post-mortem tissue from the temporal pole to reveal the cause of CADASIL specific WM hyperintensities.
Materials & Methods
A combination of tinctorial and immunostaining approaches and in vitro imaging methods were used to quantify the extent of perivascular space (PVS), arteriosclerosis determined as the sclerotic index (SI), WM myelination as the myelin index (MI) and damage within the WM as accumulated degraded myelin basic protein (dMBP) in samples of the anterior temporal pole from 9 CADASIL and 8 sporadic subcortical ischaemic vascular dementia (SIVD) cases, and 5 similar age (young) and 5 older controls. Luxol fast blue (LFB) stained serial sections from a CADASIL case were also used to reconstruct the temporal pole, which was then compared to the MR images.
LFB sections used to reconstruct the temporal pole revealed an abundance of enlarged PVS in the WM that topographically appeared as indistinct opaque regions. The mean and total areas of the PVS per WM area (%PVS) were significantly greater in CADASIL compared to the controls. The MI was severely reduced in CADASIL in relation to the SIVD and control sample that was consistent with increased immunoreactivity of dMBP, indicating myelin degeneration. Cerebral microvessels associated with the PVS exhibited a 4.5 fold greater number of basophilic (hyalinised) vessels and a 57% increase in the SI values in CADASIL subjects compared to young controls. A significant correlation between the quantity of hyalinised vessels and SI values was also apparent (P<0.05).
Our findings suggest that MRI hyperintensities in the temporal pole of CADASIL patients are explained by enlarged PVS and degeneration of myelin accompanied by lack of drainage of the interstitial fluid rather than lacunar infarcts. Consistent with the lack of MR hypersignals in the temporal pole of older SIVD subjects, our observations imply greater progression of pathological changes in CADASIL patients.
CADASIL; dementia; cognitive impairment; stroke; subcortical ischaemic vascular dementia; vascular dementia
Background and Purpose
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), caused by mutations in the NOTCH3 gene, is the most common monogenic disorder causing lacunar stroke and cerebral small vessel disease (SVD). Fabry disease (FD) due to mutations in the GLA gene has been suggested as an underdiagnosed cause of stroke, and one feature is SVD. Previous studies reported varying prevalence of CADASIL and FD in stroke, likely due to varying subtypes studied; no studies have looked at a large cohort of younger onset SVD. We determined the prevalence in a well-defined, MRI-verified cohort of apparently sporadic patients with lacunar infarct.
Caucasian patients with lacunar infarction, aged ≤70 years (mean age 56.7 (SD8.6)), were recruited from 72 specialist stroke centres throughout the UK as part of the Young Lacunar Stroke DNA Resource. Patients with a previously confirmed monogenic cause of stroke were excluded. All MRI’s and clinical histories were reviewed centrally. Screening was performed for NOTCH3 and GLA mutations.
Of 994 subjects five had pathogenic NOTCH3 mutations (R169C, R207C, R587C, C1222G and C323S) all resulting in loss or gain of a cysteine in the NOTCH3 protein. All five patients had confluent leukoaraiosis (Fazekas grade ≥2). CADASIL prevalence overall was 0.5% (95% CI 0.2%-1.1%) and among cases with confluent leukoaraiosis 1.5% (95% CI 0.6%-3.3%). No classic pathogenic FD mutations were found; one patient had a missense mutation (R118C), associated with late-onset FD.
CADASIL cases are rare and only detected in SVD patients with confluent leukoaraiosis. No definite FD cases were detected.
We report a 52-yr-old Korean woman with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) whose diagnosis was confirmed by skin biopsy and the presence of a novel mutation in the NOTCH3 gene. The patient's clinical features were rather unusual in that 1) clinical presentations were only two episodes of stroke and mild dementia unaccompanied by mood disturbances or migraine, and 2) there was no family history. Brain MRI showed T2 hyperintensities in both temporal pole areas in line with the recent suggestion by O'Sullivan et al. that the abnormality could be a radiologic marker of CADASIL. FDG-PET also showed a hypometabolism in the temporal pole areas with an abnormal finding on MRI in addition to the hypometabolism in cortical and subcortical regions. We could learn from this case that CADASIL may be included in the differential diagnoses in patients with vascular dementia associated with a small vessel disease, even in the absence of a family history, especially when there are no known stroke risk factors and when the MRI shows T2 hyperintensity in the temporal pole regions.
Arteries in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) are susceptible to smooth muscle loss and fibrosis, but the molecular components underlying these dramatic vascular changes are not well characterized. The purpose of this study was to investigate the distribution of collagen isoforms in the cerebral vessels of North American CADASIL patients with classical NOTCH3 mutations. Expression of type I-VI collagen in brains obtained at autopsy from six CADASIL patients with cysteine-altering mutations in NOTCH3 was compared to control brain expression. We identified a consistent increase of type I, III, IV, and VI collagen in CADASIL brains. Strong accumulation of type I, III, IV and VI collagen was noted in all calibers of vessels, including small and medium-sized leptomeningeal arteries, small penetrating white matter arteries, and capillaries. Within leptomeningeal arteries, where we could define the three tunicae of each vessel, we found distinct collagen subtype distribution patterns in CADASIL. Type I and III collagen were largely found in either adventitial/medial or transmural locations. Type IV collagen was strictly intimal/medial. Type VI collagen was adventitial or adventitial/medial. Within the thickened penetrating arteries of CADASIL patients, all four collagens extended through most of the arterial wall. We observed increased staining of capillaries in CADASIL for type I, IV, and VI collagen. In conclusion, brain vascular collagen subtypes are increased in CADASIL in multiple layers of all sizes of arteries, with disease-specific changes most prominent in the tunica media and thickened small penetrating vessels. In diseased arteries, type I, III, and VI collagen spreads from an external location (adventitia) into the vascular media, while type IV collagen accumulates in an internal pattern (intima and media). These observations are consistent with a pathological role for collagen accumulation in the vascular media in CADASIL.
The altered aggregation of proteins in non-native conformation is associated with endoplasmic reticulum derangements, mitochondrial dysfunction and excessive production of reactive oxygen species. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare hereditary systemic vasculopathy, caused by NOTCH3 mutations within the receptor extracellular domain, that lead to abnormal accumulation of the mutated protein in the vascular wall. NOTCH3 misfolding could cause free radicals increase also in CADASIL. Aim of the study was to verify whether CADASIL patients have increased oxidative stress compared to unrelated healthy controls. We enrolled 15 CADASIL patients and 16 gender- and age-matched healthy controls with comparable cardiovascular risk factor. Blood and plasma reduced and total aminothiols (homocysteine, cysteine, glutathione, cysteinylglycine) were measured by HPLC and plasma 3-nitrotyrosine by ELISA. Only plasma reduced cysteine (Pr-Cys) and blood reduced glutathione (Br-GSH) concentrations differed between groups: in CADASIL patients Br-GSH levels were higher (p = 0.019) and Pr-Cys lower (p = 0.010) than in controls. No correlation was found between Br-GSH and Pr-Cys either in CADASIL patients (rho 0.25, P=0.36) or in controls (rho -0.15, P=0.44). Conversely, 3-nitrotyrosine values were similar in CADASIL and healthy subjects (p = 0.82). The high levels of antioxidant molecules and low levels of oxidant mediators found in our CADASIL population might either be expression of an effective protective action against free radical formation at an early stage of clinical symptoms or they could suggest that oxidative stress is not directly involved in the pathogenesis of CADASIL.
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common heritable form of vascular dementia and it is caused by mutations in the NOTCH3 gene. The neurologic manifestations of CADASIL syndrome have been well characterized; however, here we report one of the first de novo cases of CADASIL-associated coronary artery disease. A 45-year-old woman with a history of CADASIL and remote tobacco use presented with unstable angina. She was found to have diffuse and irregular narrowing of the left anterior descending artery and a drug eluting stent was deployed. Months later, she developed two subsequent episodes of unstable angina, requiring stent placement in the distal left anterior descending artery and the right coronary artery. Though the neurologic manifestations of CADASIL have been well described, these patients may also be predisposed to developing premature coronary artery disease. Patients with CADASIL and their physicians should be aware of this possible association because these patients may not be identified as high risk by traditional cardiovascular risk estimators. These patients may benefit from more aggressive interventions to reduce cardiac risk.
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is increasingly recognized as an inherited arterial disease leading to a step-wise decline and eventually to dementia. CADASIL is caused by mutations in NOTCH3 epidermal growth factor-like repeat that maps to chromosome 19. CADASIL cases have been identified in most countries of Western and Central Europe, the Americas, Japan, Australia, the Caribbean, South America, Tanzania, Turkey, South Africa and Southeast Asia, but not in Arabs.
We studied three families from Saudi Arabia (Family A), Kuwait (Family B) and Yemen (Family C) with 19 individuals affected by CADASIL.
The mean age of onset was 31 ± 6 and the clinical presentation included stroke in 68%, subcortical dementia in 17% and asymptomatic leukoariosis detected by MRI in 15%. Migraine and depression were frequently associated, 38% and 68% respectively. The mean age of death was 56 ± 11. All NOTCH3 exons were screened for mutations, which revealed the presence of previously reported mutations c.406C>T (p.Arg110>Cys) in two families (family A&B) and c.475C>T (p.Arg133>Cys) mutation in family C.
CADASIL occurs in Arabs, with clinical phenotype and genotype similar to that in other ethnic groups.
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare hereditary small vascular disease and its mainly clinical manifestations are ischemic events. Spontaneous intracerebral hemorrhage (ICH) involvement in patients with CADASIL is extremely uncommon.
A 46-year-old normotensive Chinese man developed a large hematoma in the left basal ganglia after he was diagnosed with CADASIL 2 months ago, the patient did not take any antithrombotics. Susceptibility weighted imaging at pre-ICH showed multiple cerebral microbleeds (CMBs) in the bilateral basal ganglia. He experienced migraine at about 10 months post-ICH. To our knowledge, this is the first report of ICH in CADASIL patients with Arg90Cys mutation in exon 3.
Discussion and conclusions
ICH should be considered when evaluating new attacks in CADASIL patients. Thus, MRI screening for CMBs might be helpful in predicting the risk of ICH and guiding antithrombotic therapy. In addition, strict control of hypertension and cautious use of antithrombotics may be important in this context.
Migraine; CADASIL; Intracerebral hemorrhage; NOTCH3; Microbleeds
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary small vessel disease caused by mutations of the Notch3 gene. Clinical manifestations include migraine with or without aura, psychiatric disorders, recurrent ischaemic strokes and cognitive decline. Brain MRI shows confluent hyperintense signal alterations involving characteristically the anterior part of the temporal lobes and widespread areas of the deep and periventricular white matter. Focal or generalised seizures represent a rare neurological manifestation in CADASIL with a frequency of 6–10% in two large series.1,2 Status epilepticus, however, has not been reported so far. Herein we describe a patient with CADASIL with an acute focal neurological deficit following a prolonged migraine attack. The symptoms were first interpreted as an ischaemic stroke but subsequently diagnosed to be due to a non-convulsive status epilepticus.
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary small vessel disease caused by mutations of the Notch3 gene. Clinical manifestations include migraine with or without aura, psychiatric disorders, recurrent ischaemic strokes and cognitive decline. Brain MRI shows confluent hyperintense signal alterations involving characteristically the anterior part of the temporal lobes and widespread areas of the deep and periventricular white matter. Focal or generalised seizures represent a rare neurological manifestation in CADASIL with a frequency of 6–10% in two large series. Status epilepticus, however, has not been reported so far. Herein we describe a patient with CADASIL with an acute focal neurological deficit following a prolonged migraine attack. The symptoms were first interpreted as an ischaemic stroke but subsequently diagnosed to be due to a non-convulsive status epilepticus.
CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy) is a hereditary small vessel disease caused by mutations in the NOTCH3 gene, leading to toxic NOTCH3 protein accumulation in the small- to medium sized arterioles. The accumulation is systemic but most pronounced in the brain vasculature where it leads to clinical symptoms of recurrent stroke and dementia. There is no therapy for CADASIL, and therapeutic development is hampered by a lack of feasible clinical outcome measures and biomarkers, both in mouse models and in CADASIL patients. To facilitate pre-clinical therapeutic interventions for CADASIL, we aimed to develop a novel, translational CADASIL mouse model.
We generated transgenic mice in which we overexpressed the full length human NOTCH3 gene from a genomic construct with the archetypal c.544C > T, p.Arg182Cys mutation. The four mutant strains we generated have respective human NOTCH3 RNA expression levels of 100, 150, 200 and 350 % relative to endogenous mouse Notch3 RNA expression. Immunohistochemistry on brain sections shows characteristic vascular human NOTCH3 accumulation in all four mutant strains, with human NOTCH3 RNA expression levels correlating with age at onset and progression of NOTCH3 accumulation. This finding was the basis for developing the ‘NOTCH3 score’, a quantitative measure for the NOTCH3 accumulation load. This score proved to be a robust and sensitive method to assess the progression of NOTCH3 accumulation, and a feasible biomarker for pre-clinical therapeutic testing.
This novel, translational CADASIL mouse model is a suitable model for pre-clinical testing of therapeutic strategies aimed at delaying or reversing NOTCH3 accumulation, using the NOTCH3 score as a biomarker.
Electronic supplementary material
The online version of this article (doi:10.1186/s40478-015-0268-1) contains supplementary material, which is available to authorized users.
CADASIL; NOTCH3; Transgenic mouse model; Biomarker