SVOA Paediatrics

ANTOUN Christophe¹, MAALOUF George¹, SHAIB Mohamad¹, RACHKIDI Joseph², MAKARY Mabelle³, MEGARBANE Andre^4-5, MANSOUR Hicham^1,6*

¹Faculty of Medicine, Saint George University of Beirut, Beirut, Lebanon.

²Department of Pediatrics, Nini Hospital, Tripoli, Lebanon.

³Department of Pediatric Nephrology Rheumatology and Dermatology, HFME, Bron, France.

⁴Department of Human Genetics, Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Lebanon.

⁵Institut Jerome Lejeune, Paris, France.

⁶Department of Pediatrics, Saint George University Medical Center, Beirut, Lebanon.

*Corresponding Author: MANSOUR Hicham, Department of Pediatrics, Saint George University Medical Center, Beirut, Lebanon.

https://doi.org/10.58624/SVOAPD.2026.05.013

Received: May 18, 2026

Published: June 03, 2026

Citation: Antoun C, Maalouf G, Shaib M, Rachkidi J, Makary M, Megarbane A, Mansour H. Aminoacylase-1 Deficiency in a Lebanese Infant with a Novel Homozygous Variant. SVOA Paediatrics 2026, 5:3, 93-96. doi: 10.58624/SVOAPD.2026.05.013

Abstract

Aminoacylase 1 (ACY1) deficiency is a rare autosomal recessive inborn error of metabolism characterized by impaired hydrolysis of N-acetylated amino acids and a broad clinical spectrum, including developmental delay, seizures, and hypotonia. Fewer than 20 cases have been reported worldwide. Here we present the first reported case of ACY1 deficiency in a Lebanese infant born to consanguineous parents, highlighting the diagnostic challenges and phenotypic variability associated with this disorder. Whole exome sequencing (WES) identified a novel unreported homozygous variant in the ACY1 gene, despite an otherwise normal biochemical screen. This case expands the clinical and genetic spectrum of ACY1 deficiency and underscores the importance of genetic testing in patients with unexplained neurodevelopmental delay.

Keywords: ACY1 deficiency, Aminoacylase 1, Neurodevelopmental delay, Consanguinity, Whole exome sequencing, Lebanon.