Skin and sural nerve biopsies: ultrastructural findings in the first genetically confirmed cases of CADASIL in Serbia.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited vascular disorder caused by Notch3 gene mutations. The main histopathological hallmark is granular osmiophilic material (GOM) deposited in the close vicinity of vascular smooth muscle cells (VSMCs). The authors report the first 7 ultrastructurally and genetically confirmed cases of CADASIL in Serbia. Samples of skin and sural nerve were investigated by transmission electron microscopy. GOM deposits were observed around degenerated VSMCs in all the skin biopsies examined. Sural nerve biopsies revealed severe alterations of nerve fibers, endoneurial blood vessels with GOM deposits, endoneurial fibroblasts, and perineurial myofibroblasts. Total genomic DNA was extracted from peripheral blood leukocytes, and exons 2-6 of the Notch3 gene were amplified by PCR and subsequently sequenced. Four different mutations in exons 2 (Cys65Tyr), 3 (Gly89Cys and Arg90Cys), and 6 (Ala319Cys), which determine the CADASIL disease, were detected among all described patients. A novel missense mutation Gly89Cys involving exon 3 was detected. Due to the difficulties in the determination of the Notch3 mutations, these data suggest that electron microscopic analysis for GOMs in dermal vessel wall provides a rapid and reliable screening method for this disease.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy.

INTRODUCTION: Fast and precise diagnostics of the disease from the large group of adult leukoencephalopathy is difficult but responsible job, because the outcome of the disease is very often determined by its name. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is caused by the mutation of Notch 3 gene on chromosome locus 19p13. Beside the brain arterioles being the main disease targets, extracerebral small blood vessels are affected by the pathological process. Clinically present signs are recurrent ischemic strokes and vascular dementia. CADASIL in its progressive form shows a distinctive pattern of pathological changes on MRI of endocranium. The diagnosis is confirmed by the presence of granular osmiophilic material (GOM) in histopathological skin biopsies. CASE REPORTS: Two young adult patients manifested ischemic strokes of unknown etiology, cognitive deterioration, migraine and psychopathological phenomenology. MRI of endocranium pointed on CADASIL. Ultrastructural examination of skin biopsy proved the presence of GOM in the basal lamina and near smooth muscle cells of arteriole dermis leading to CADASIL diagnosis. The presence of GOM in histopathological preparation is 100% specific for CADASIL. The patients were not searched for mutation in Notch 3 gene on chromosome 19, because some other leukoencephalopathy was disregarded. CONCLUSION: Suggestive clinical picture, distinctive finding of endocranium MRI, the presence of GOM by ultrastructural examination of histopathological skin biopsies are sufficient to confirm CADASIL diagnosis.

[Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL)--three case reports from Serbia].

INTRODUCTION: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary microangiopathy leading to recurrent strokes and vascular dementia in young and middle-aged patients. The diagnosis of CADASIL is based on typical clinical presentation and characteristic magnetic resonance imaging (MRI) changes, and has to be confirmed by biopsy of the sural nerve, muscle and skin, as well as by genetic analysis. Mutations within the Notch3 gene were identified as the underlying genetic defect in CADASIL. CASE OUTLINE: The clinical manifestations of the first presented patient with migraine from the age of thirteen, stroke without vascular risk factors and stepwise progression of vascular dementia comprising the typical clinical picture of CADASIL, were confirmed after seven years with pathological verification. The second presented case did not satisfy the clinical criteria for CADASIL. His stroke was considered to be related with vascular risk factors--diabetes mellitus and hypertension. The aetiological diagnosis was established only when his brother without vascular risk factors presented with similar clinical manifestations. CONCLUSION: Until the development of the new neuroimaging techniques like MRI, pathologic and genetic analysis, CADASIL was considered as a rare disorder. However, the increasing number of CADASIL families has been identified throughout the world showing that this entity is usually underdiagnosed. This article presents three patients from two Serbian families with clinical suspicion of CADASIL verified by pathologic examination.