Persistent fifth aortic arch associated with 22q11.2 deletion syndrome

Area of Science:

• Genetics and Developmental Biology
• Pediatric Cardiology
• Clinical Genetics

Background:

• Chromosome 22q11.2 deletion is a known cause of conotruncal malformations and aortic arch anomalies.
• Persistent fifth aortic arch is a rare congenital anomaly.
• The association between these conditions and 22q11.2 deletion requires further investigation.

Purpose of the Study:

• To investigate the association between chromosome 22q11.2 deletion and clinical manifestations in pediatric patients presenting with persistent fifth aortic arch.
• To identify common phenotypic features in patients with both persistent fifth aortic arch and conotruncal malformations.

Main Methods:

• Retrospective analysis of four pediatric patients diagnosed with persistent fifth aortic arch and conotruncal malformations.
• Review of clinical data, imaging studies (echocardiograms, angiograms), surgical findings, and cytogenetic analysis.
• Evaluation for cardinal phenotypic features of 22q11.2 deletion syndrome.

Main Results:

• All four patients exhibited cardinal phenotypic features of 22q11.2 deletion syndrome.
• These features included cardiovascular malformations, abnormal facies, thymic hypoplasia, palatal anomalies, and hypocalcemia.
• Cytogenetic studies confirmed chromosome 22q11.2 deletion in all four patients.

Conclusions:

• The co-occurrence of congenital conotruncal malformations and aortic arch anomalies, such as persistent fifth aortic arch, should raise suspicion for chromosome 22q11.2 deletion.
• Presence of any additional cardinal phenotypic feature strengthens the suspicion for 22q11.2 deletion.
• Genetic testing for 22q11.2 deletion is recommended in pediatric patients with these combined anomalies.