Objective:

To illustrate a case of radiographic white matter lesions found to be tuberous sclerosis complex and the importance of expanding differentials when imaging does not fit a particular pattern.

Background:

Tuberous sclerosis complex (TSC) is a genetic disorder caused by mutation in the TSC1 or TSC2 gene presenting with typically benign tumors of the central nervous system, heart, kidney, eyes, skin, and pancreas. The most common neurological symptoms of TSC are seizures, intellectual disability, and autism. Neuroimaging often demonstrates CNS tumors including glioneuronal hamartomas (a.k.a. cortical tubers), subependymal nodules, and subependymal giant cell astrocytomas. 

Design/Methods:

Case report 

Results:

A 22-year-old developmentally normal female with a history of pancreatic neuro-endocrine tumor, renal cysts, and congenital right eye blindness presented with near daily headaches for ten months initially concerning for migraines. MRI brain showed multifocal bilateral subcortical T2 FLAIR hyperintense lesions and a single left subependymal lesion. Radiographic report raised concern for multiple sclerosis. Lesions however lacked features commonly described in demyelinated plaques such as oval shaped, well circumscribed nature, and were absent from the infratentorial region and spinal cord. CSF studies were unremarkable with absence of oligoclonal bands. Clinical findings from other organ systems including hypopigmented cutaneous lesions, renal cysts, and dental enamel pits raised concern for tuberous sclerosis. Further genetic testing revealed a heterozygous pathogenic variant in the TSC1 gene, confirming the diagnosis of autosomal dominant TSC. 

Conclusions:

Nonspecific white matter lesions are commonly found in routine imaging. Although T2 hyperintense lesions in the juxtacortical white matter raise suspicion for multiple sclerosis, additional radiographic characteristics should be considered. In this case, imaging findings were later identified as cortical glioneuronal hamartomas (i.e. cortical tubers) consistent with the diagnosis of tuberous sclerosis complex. The patient did not have typical neurological symptoms associated with TSC.