Cranial, Renal, and Skeletal Anomalies in a Fetus With a Pathogenic Variant in the TAFAZZIN Gene

To report a case of a fetus with multiple congenital anomalies and suspected Barth syndrome, highlighting potential phenotypic expansion of the syndrome.

A 32-year-old G4P2011 patient was referred at 18w5d gestation for suspected fetal encephalocele. Serial imaging, including ultrasound and MRI, was performed to evaluate fetal anomalies. Doppler studies assessed fetal development and postnatal findings were documented. Genetic variants were identified using trio whole exome sequencing.

Initial ultrasound revealed occipital encephalocele, right renal aplasia, and abnormal vertebral curvature. Follow-up MRI confirmed occipital encephalocele and identified Chiari malformation but normal renal morphology. Phenotypic evolution included intrauterine growth restriction (IUGR), right renal hypoplasia, cardiomegaly, polyhydramnios, and hydrops fetalis. Delivery occurred via cesarean section at 30w6d due to non-reassuring Doppler findings. Postnatally, the neonate exhibited esophageal atresia, vertebral segmentation and rib morphology defects, and right renal aplasia. The neonate died on the first day of life due to cardiac decompensation. Genetic testing identified a TAFAZZIN c.589G>A p.(Gly197Arg) pathogenic variant, consistent with Barth syndrome.

The presentation of IUGR, cardiomyopathy, and hydrops fetalis aligns with Barth syndrome. However, the additional findings of occipital encephalocele, renal aplasia, and vertebral and rib anomalies suggest a potential phenotypic expansion of Barth syndrome.