What is (are) multiple sulfatase deficiency ?
Multiple sulfatase deficiency is a condition that mainly affects the brain, skin, and skeleton. Because the signs and symptoms of multiple sulfatase deficiency vary widely, researchers have split the condition into three types: neonatal, late-infantile, and juvenile.  The neonatal type is the most severe form, with signs and symptoms appearing soon after birth. Affected individuals have deterioration of tissue in the nervous system (leukodystrophy), which can contribute to movement problems, seizures, developmental delay, and slow growth. They also have dry, scaly skin (ichthyosis) and excess hair growth (hypertrichosis). Skeletal abnormalities can include abnormal side-to-side curvature of the spine (scoliosis), joint stiffness, and dysostosis multiplex, which refers to a specific pattern of skeletal abnormalities seen on x-ray. Individuals with the neonatal type typically have facial features that can be described as "coarse." Affected individuals may also have hearing loss, heart malformations, and an enlarged liver and spleen (hepatosplenomegaly). Many of the signs and symptoms of neonatal multiple sulfatase deficiency worsen over time.  The late-infantile type is the most common form of multiple sulfatase deficiency. It is characterized by normal cognitive development in early childhood followed by a progressive loss of mental abilities and movement (psychomotor regression) due to leukodystrophy or other brain abnormalities. Individuals with this form of the condition do not have as many features as those with the neonatal type, but they often have ichthyosis, skeletal abnormalities, and coarse facial features.  The juvenile type is the rarest form of multiple sulfatase deficiency. Signs and symptoms of the juvenile type appear in mid- to late childhood. Affected individuals have normal early cognitive development but then experience psychomotor regression; however, the regression in the juvenile type usually occurs at a slower rate than in the late-infantile type. Ichthyosis is also common in the juvenile type of multiple sulfatase deficiency.  Life expectancy is shortened in individuals with all types of multiple sulfatase deficiency. Typically, affected individuals survive only a few years after the signs and symptoms of the condition appear, but life expectancy varies depending on the severity of the condition and how quickly the neurological problems worsen.