A Rare Neonatal Case of 48,XXYY Syndrome Presenting With Ambiguous Genitalia and Tetralogy of Fallot.

Neonatal 48,XXYY syndrome can present with both ambiguous genitalia and Tetralogy of Fallot, a striking and previously unreported association. This case broadens the phenotypic spectrum and underscores the importance of integrating genetic and cardiac evaluation in all neonates with disorders of sex development.