Molecular diagnosis of tuberous sclerosis complex in fetuses and infants: an institutional case series.

Objective: We describe the clinical and genetic characteristics of fetuses and infants diagnosed with tuberous sclerosis complex (TSC) in our centre, prenatally or neonatally, for a better understanding of the benefits of early screening.

Methods: In this retrospective study, we analysed the data on one fetus and nine infants with a definitive TSC diagnosis by genetic criteria (five patients carrying TSC1 variants and 5 patients carrying TSC2 variants). We explored the differences between phenotypes of patients carrying TSC1 and TSC2 pathogenic variants.

Results: The most common initial presenting features of TSC were cardiac rhabdomyomas (CRs) that were observed in nine out of ten patients. The most common postnatal features, besides CR, were presented with subependymal nodules-in five patients, and hypomelanotic macules-in four patients. In total, 10 variants causing TSC were detected in this study, including 5 novel variants. We demonstrated that patients with TSC2 variants had earlier onset and more severe clinical manifestations compared with patients carrying TSC1 variants.

Conclusion: Early diagnosis of TSC improves genetic counselling and perinatal management.