P2A154: A Rare Case of Tuberous Sclerosis Associated with Abdominal Aortic Aneurysm in Infancy

Introduction: Aortic aneurysms are a known but rare clinical manifestation of tuberous sclerosis complex (TSC). Unfortunately, the diagnosis is often missed, and most are incidentally found when patients are either symptomatic or when the aneurysm has ruptured. We present one of the youngest cases of TSC-associated infra-renal aortic aneurysm in an 11-month-old infant.

Case Description: A twin infant male born at 35 weeks gestation was found to have numerous cardiac rhabdomyomas on prenatal ultrasound. Postnatal echocardiogram confirmed the presence of the rhabdomyomas, with no intracardiac obstruction or valvular insufficiency. Molecular genetic testing identified a pathogenic TSC2 variant. Additional imaging at the time of diagnosis consisted of an abdominal ultrasound without renal anomalies or cystic disease and magnetic resonance imaging (MRI) of the brain significant for subependymal nodules. Physical examination was appropriate for his age without cutaneous findings associated with TSC, and family members did not have features of TSC. After discharge, he received appropriate follow-up care from cardiology, nephrology, neurology, and genetics. He was routinely monitored with renal ultrasound, EEG, ECG, Holter monitor, and echocardiograms. Although without clinical seizures, Vigabatrin was started due to an abnormal EEG. Follow up brain MRI was to be coordinated with abdominal MRI, but at 11 months of age, the infant expired after sudden onset of pallor and decreased responsiveness. The autopsy revealed a ruptured 7 x 7 cm infra-renal abdominal aortic aneurysm associated with retroperitoneal hemorrhage and hematoma as the cause of death.

Discussion: There are reported cases in the literature regarding TSC aortic aneurysms, although presentation in infancy has rarely been reported. 2021 surveillance guidelines recommend MRI of the brain and abdomen as the preferred modality to assess for the presence of brain pathologies (tubers, subependymal nodules, migrational defects) and renal angiomyolipomas and cysts at the time of diagnosis regardless of age. Although these guidelines exist, there are currently no established recommendations for evaluating aortic aneurysms at the time of TSC diagnosis or further in age unless clinically warranted. However, prior reviews have noted that aneurysms may be found incidentally or only after rupture has already taken place. Salerno et. al estimated a mortality rate of 29% directly attributable to aortic aneurysms in their literature review.

Conclusion: TSC is a well-known and relatively common disorder with extensive multisystemic surveillance recommendations. While aortic aneurysm has been described in association with TSC previously, guidelines have not specifically addressed this in anticipatory screening. Due to its often fatal nature, screening and surveillance for aortic aneurysms should be part of the care for patients with TSC and should begin at the time of diagnosis.