Unusual clinical presentation of tuberless tuberous sclerosis complex

Cortical tubers are the hallmark of tuberous sclerosis. Their presence is expected on brain imaging, especially when seizures begin before 1 year of age with concomitant significant developmental delay. Increased tuber counts have been reported to be associated with seizures and poor cognitive outcome. We present a 3-year-old girl with intractable seizures that started as infantile spasms at 2 months of age and who was diagnosed with clinically definitive tuberous sclerosis. Poor prognostic signs included multiple seizure types, seizure onset before 1 year of age, and multifocal electroencephalographic abnormalities. However, on repeated brain magnetic resonance imaging scans, the known radiological findings associated with tuberous sclerosis complex were absent, raising a diagnostic dilemma. Therefore, genetic analysis was performed. A mutation was detected in the TSC2 gene, confirming the diagnosis. To the best of our knowledge, this is the first reported case of tuberless tuberous sclerosis complex associated with intractable epilepsy and developmental delay.