Congenital focal lymphedema as a diagnostic clue to tuberous sclerosis complex: report of two cases diagnosed by ultrasound.

Tuberous sclerosis complex (TSC) is a familial disorder characterized by benign hamartomas in the brain and other organs. Generally, the diagnosis of TSC is relatively easy, based on a medical history, a physical examination, and imaging findings. However, it can be difficult to consider a possibility of TSC in neonates and infants when congenital lymphedema is the sole external manifestation, because lymphedema associated with TSC is extremely rare. Herein, we report two cases of TSC showing congenital lymphedema at the initial presentation. Both patients were girls, and their sole complaint was congenital lymphedema. We diagnosed TSC using ultrasound focusing on the kidney, heart, and brain in addition to the extremity showing lymphedema. Awareness of a potential association of congenital lymphedema with TSC may assist in the diagnosis of TSC by ultrasound.