Unusual Presentation of Classical Galactosemia: A Case Report of Iranian Experience.

Galactosemia is a rare autosomal recessive metabolic disorder with four main types, and classic galactosemia is the most prevalent. These patients have galactose-1-phosphate-uridyltransferase deficiency. We report on a case of an infant who was admitted with poor feeding, lethargy, and poor weight gain. Based on the clinical symptoms and laboratory findings, the patient was considered to have a metabolic disorder. The patient had unusual presentations such as macrocytic anemia requiring blood transfusions, repeatedly metabolic acidosis requiring bicarbonate therapy and failure to thrive in addition to neurodevelopmental delay which led the authors to different diagnoses and suspect to mitochondrial disorders. Finally, in one of the assessments before blood transfusion, a high galactose-1 phosphate was detected, and galactose-free diet was started which led to neurologic and physical of the child. The whole-exome sequencing (WES) also revealed a likely pathogenic homozygous mutation in GALT (c.794 C>G, p. Pro265Arg) confirming the diagnosis of classic galactosemia. In Iran, global neonatal metabolic screening is not done for galactosemia which results in late diagnosis of the affected patients. So, we suggest adding galactosemia to neonatal metabolic screening in Iran.