Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 53 10 2015 10 27 656 658 EN Mehri Najafi Sani Department of Pediatric Gastroenterology, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran. Mitra Ahmadi Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran. Pejman Roohani Department of Pediatric Gastroenterology, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran. Nima Rezaei Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran. َAND Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. AND 4Universal Scientific Education and Research Network (USERN), Tehran, Iran. 2015 10 27 Zellweger syndrome (ZS) is a peroxisomal disorder with a multiple congenital anomalies, characterized by stereotypical facies, profound hypotonia, organ involvement including cerebral, retinal, hepatic, and renal. Herein, a 3-month-old female with ZS is presented who was referred because of increased liver enzymes (subclinical hepatitis), which was detected in work-up of her neck cyst, severe hypotonia, and abnormal facies. An increased concentration of very long chain fatty acid in lipid profile was detected. ZS should be considered in the list of differential diagnosis in infants with stereotypical phenotype, neurodevelopmental delay, and severe hypotonia in association with liver and other organs involvement. https://acta.tums.ac.ir/index.php/acta/article/view/5082 https://acta.tums.ac.ir/index.php/acta/article/download/5082/4706