Brachial and subclavian arteries aneurysms due to tuberous sclerosis complex mechanisms – case report and literature review

Introduction : Tuberous sclerosis complex (TSC) is a rare autosomal dominant condition characterized by cutaneous, cerebral, and other multiorgan involvement. Aneurysms due to TSC pathogenic mechanism are rarely present, mainly aortic, renal, or intracranial and very few associated with peripheral circulation. A TSC patient, aged 31 years, who developed brachial and subclavian arteries aneurysms is presented. The question of a random association of the aneurysms with TSC versus aneurysms within pathogenic released mammalian target of rapamycin (mTOR) pathway effect was raised. Case presentation : Patient’s file, available from the age of six months, was analyzed for demonstration of the TSC diagnosis. Patient was examined, and cerebral magnetic resonance imaging (MRI) was repeated. Surgery and angiographic reports and images were reviewed. Pathology of the aneurysmal wall available from surgery was reexamined and special stainings and immunohistochemistry markers were applied. Genetic characterization of the patient was performed. Definite TSC was diagnosed based on major criteria [ungual fibromas, shagreen patch, cortical tubers, subependymal nodules (SENs), subependymal giant cell astrocytoma (SEGA)], minor criteria (confetti skin lesions, dental enamel pits, gingival fibromas), genetic result showing heterozygous variant in exon 8 of TSC1 gene ( c.733C>T-p.Arg245* ). Pathology analysis revealed markedly thickened aneurysmal wall due to smooth muscle cells (SMCs) proliferation in media and neoformation vessels with similar characteristics in the aneurysmal wall. Discussions and Conclusions : This is a rare case with aneurysms related to TSC, with an exceptional peripheral localization. Pathology exam is the key investigation in demonstrating the TSC-related pathogenic mechanism. A literature review showed 73 TSC cases presenting aneurysms published until now.