Multiple sulphatase deficiency (MSD) is an inherited disorder that is caused by the accumulation of different compounds in cells throughout the body that cannot be broken down. This is due to a dysfunctional enzyme called formylglycine-generating enzyme. The most severe type of MSD has an onset of symptoms soon after birth, though the majority of children with MSD will begin to show symptoms in their first or second year of life. Tissue in the nervous system quickly begins to deteriorate, leading to movement problems, seizures, intellectual disability and slow development. Skeletal abnormalities may also be seen, as well as dry, scaly, itchy skin. Affected children usually have facial features that are referred to as "coarse" and some will have hearing loss. Major organs may also be affected, including the heart, liver and spleen. In rare cases, symptoms do not appear until mid-to late childhood. Typically survival is only for a few years after symptoms begin to show. There is no cure for MSD but medical surveillance and care may help to improve some symptoms and overall condition of life. MSD is caused by pathogenic variants in the SUMF1 gene.