Inborn errors of metabolism (IEM) constitute a heterogeneous group of single gene diseases, which cause the deficiency of critical enzymes involved in cell metabolism. The enzymatic insufficiency leads to the disruption of critical biological pathways, with accumulation of toxic metabolites in different human cells and tissues. This can lead to complex, life-threatening syndromes, affecting the skeletal structure, vision, hearing, cardiopulmonary function and neurological development. The reported cumulative incidence of IEM differs across the world, with an estimated incidence of 1:667 in Saudi Arabia and 1:2920 in Germany. 1 Current therapeutic strategies for IEM are directed towards reducing critical substrates, removing toxic metabolites or increasing the activity of the defective enzyme.Enzyme-replacement therapy (ERT) relies on the recombinant production of highly purified enzymes administered to patients affected by a number of IEM, in order to crosscorrect tissues and organs suffering from that enzymatic