Cardiac rhabdomyoma and renal cyst in a fetus: early onset of tuberous sclerosis with renal cystic disease

Diagnosis of tuberous sclerosis complex in the fetus

Tuberous sclerosis complex is a dominantly inherited genetic disorder of striking clinical variability. It is caused by mutations in either TSC1 or TSC2 gene, which regulate cell growth and proliferation by inhibition of mTORC1 signaling. TS is characterized by the development of benign tumors in many tissues and organs and its neurological manifestations include epilepsy, autism, cognitive and behavioral dysfunction, and giant cell tumors. With mechanism-based mTOR inhibitors therapy now available for many of its manifestations, early diagnosis of TSC is very important in order to offer appropriate care, long-term surveillance and parental counseling. Fetal ultrasound and MRI imaging techniques have evolved and may capture even earlier the following TSC-associated lesions: cardiac rhabdomyomas, subependymal nodules, cortical tubers and renal cysts. Often these represent an incidental finding during a routine ultrasound. Furthermore, in the past decades prenatal molecular diagnosis of TSC has emerged as an important option for families with a known affected member; however, the existing evidence with regards to the clinical characteristics and long-term outcome of babies diagnosed prenatally with TSC is yet limited and the path that follows early TSC detection merits further research.

Fetal cardiac tumors: clinical features, management and prognosis

Fetal cardiac tumors are rare and usually benign. While echocardiography is a reliable technique for diagnosing fetal cardiac tumors, their definitive diagnosis relies on pathological examination. The strategies used to manage fetal cardiac tumors are challenging. A good clinical result is their complete regression during pregnancy or shortly after birth, as often occurs with cardiac rhabdomyomas. Moreover, the fetal prognosis depends on the nature of the tumors, namely, their location, size, number and associated complications. The active treatment options for symptomatic fetuses depend on the fetal status and may include fetal open surgery, postnatal tumor resection with or without the bridge of intrauterine pericardiocentesis, and thoracoamniotic shunting. The ex utero intrapartum treatment procedure provides an alternative technique for performing fetal open surgery and has shown promising preliminary results in selected cases, but is invasive for both the mother and fetus.

Prenatal sonographic diagnosis of tuberous sclerosis complex

We report the case of a male fetus with tuberous sclerosis complex (TSC), in whom multiple cardiac rhabdomyomas and renal angiomyolipomas were detected at 33 weeks by ultrasound with additional brain lesions detected on MRI, all confirmed after birth. DNA analysis of the TSC2 gene detected a de novo mutation in the TSC2 gene. Postnatal follow-up and neurological examination were normal, as were the results of Holter monitoring.