Clinical pregenetic screening for stroke monogenic diseases: Results from lombardia GENS registry

BACKGROUND AND PURPOSE: Lombardia GENS is a multicentre prospective study aimed at diagnosing 5 single-gene disorders associated with stroke (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, Fabry disease, MELAS [mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes], hereditary cerebral amyloid angiopathy, and Marfan syndrome) by applying diagnostic algorithms specific for each clinically suspected disease METHODS: We enrolled a consecutive series of patients with ischemic or hemorrhagic stroke or transient ischemic attack admitted in stroke units in the Lombardia region participating in the project. Patients were defined as probable when presenting with stroke or transient ischemic attack of unknown etiopathogenic causes, or in the presence of <3 conventional vascular risk factors or young age at onset, or positive familial history or of specific clinical features. Patients fulfilling diagnostic algorithms specific for each monogenic disease (suspected) were referred for genetic analysis. RESULTS: In 209 patients (57.4\ub114.7 years), the application of the disease-specific algorithm identified 227 patients with possible monogenic disease. Genetic testing identified pathogenic mutations in 7% of these cases. Familial history of stroke was the only significant specific feature that distinguished mutated patients from nonmutated ones. The presence of cerebrovascular risk factors did not exclude a genetic disease. CONCLUSIONS: In patients prescreened using a clinical algorithm for monogenic disorders, we identified monogenic causes of events in 7% of patients in comparison to the 1% to 5% prevalence reported in previous series

Lombardia GENS: a collaborative registry for monogenic diseases associated with stroke.

The Italian region of Lombardy, with its existing stroke centers and high-technology laboratories, provides a favorable context for studying monogenic diseases associated with stroke. The Lombardia GENS project was set up to create a regional network for the diagnosis of six monogenic diseases associated with stroke: CADASIL, Fabry disease, MELAS, familial and sporadic hemiplegic migraine, hereditary cerebral amyloid angiopathy and Marfan syndrome. The network comprises 36 stroke centers and seven high-technology laboratories, performing molecular analysis. In this context, all stroke/TIA patients fulfilling clinical criteria for monogenic diseases are currently being included in an ongoing study. Demographic, clinical and family data and diagnostic criteria are collected using standardized forms. On the basis of stroke incidence in Lombardy and the reported prevalence of the diseases considered, we expect, during the course of the study, to collect datasets and DNA samples from more than 200 stroke patients suspected of having monogenic diseases. This will allow evaluation of the regional burden and better phenotype characterization of monogenic diseases associated with stroke

The role of clinical and neuroimaging features in the diagnosis of CADASIL

Background: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common familial cerebral small vessel disease, caused by NOTCH3 gene mutations. The aim of our study was to identify clinical and neuroradiological features which would be useful in identifying which patients presenting with lacunar stroke and TIA are likely to have CADASIL. Methods: Patients with lacunar stroke or TIA were included in the present study. For each patient, demographic and clinical data were collected. MRI images were centrally analysed for the presence of lacunar infarcts, microbleeds, temporal lobe involvement, global atrophy and white matter hyperintensities. Results: 128 patients (mean age 56.3 \ub1 12.4\ua0years) were included. A NOTCH3 mutation was found in 12.5% of them. A family history of stroke, the presence of dementia and external capsule lesions on MRI were the only features significantly associated with the diagnosis of CADASIL. Although thalamic, temporal pole gliosis and severe white matter hyperintensities were less specific for CADASIL diagnosis, the combination of a number of\ua0these factors together with familial history for stroke result in a higher positive predictive value and specificity. Conclusions: A careful familial history collection and neuroradiological assessment can identify patients in whom NOTCH3 genetic testing has a higher yield