Situs Inversus Totalis: A Case Report and Literature Review

Situs Inversus Totalis (SIT) is a rare congenital anomaly characterized by the complete mirror-image transposition of the thoracoabdominal viscera. Although typically it has a favorable prognosis, SIT can be associated with ciliopathy-related disorders, most notably Primary Ciliary Dyskinesia (PCD). Consequently, challenges persist in the prenatal detection and subsequent genetic counseling for this condition. We present the case of a fetus diagnosed with Situs Inversus Totalis (SIT) via routine prenatal ultrasound and subsequent fetal echocardiography. Chromosomal Microarray (CMA) results were unremarkable, yet Whole Exome Sequencing (WES) revealed compound heterozygous pathogenic variants in the DNAH11 gene, inherited from each parent. Notably, no other structural malformations were detected. Following comprehensive counseling, the family opted for termination of pregnancy at 35 weeks' gestation. No postnatal examination (autopsy) was performed. This case underscores the critical role of detailed imaging, comprehensive genetic testing, and multidisciplinary team (MDT) counseling in the prenatal evaluation of Situs Inversus Totalis (SIT).