Novel TSC1 Gene Mutation in a Familial Case of Tuberous Sclerosis Complex: A Case Report

Abstract

Introduction: Tuberous sclerosis complex (TSC) is a genetic disorder that can arise from sporadic or inherited mutations in TSC1 or TSC2 genes. It is characterized by tumors in multiple organs that result in broad clinical manifestations, usually affecting the central nervous system. Diagnosis is based upon clinical criteria that require careful clinical examination along with imaging and the availability of genetic testing to assess gene mutations linked to this disorder. We present a familial case of tuberous sclerosis complex with multiple subtle clinical manifestations and novel TSC1 mutation that were diagnosed in adulthood. This report adds to the growing literature on TSC1 gene by correlating specific nucleotide substitutions with possible secondary clinical manifestations. Case presentation: A 21 year-old Hispanic female presented with history of epilepsy onset in early childhood. Upon clinical examination and imaging testing, she was found to have lesions on her scalp, eyes and brain. Her mother is 51 years old with long-standing history of epilepsy with multiple lesions on skin, eyes, and similar findings in brain imaging to daughter. No additional family history was obtained suggestive of tuberous sclerosis complex. Conclusion: Milder forms of tuberous sclerosis complex can remain undiagnosed until adolescence and adulthood, which may lead to treatment delay and complications due to the lack of regular follow-up care. In this case report, both individuals’ presenting symptom was epilepsy and later other clinical findings were linked to the disorder. Additionally, a novel DNA sequence variant was detected, which expands our knowledge of known TSC1 gene mutations. Although these genetic test results cannot be used alone to make a definite diagnosis, they suggest an association to TSC given the clinical manifestations and family history.