Multiple Sulfatase Deficiency
What is Multiple Sulfatase Deficiency?
Multiple sulfatase deficiency is a lysosomal stage disorder which primarily affects the brain, skin, and skeleton. The deficiency, a form of metabolic disorder, occurs as a result of poorly functioning enzymes known as sulfatase enzymes. Due to the wide range of symptoms, researchers have categorized multiple sulfatase deficiency into three groups: neonatal, late-infantile, and juvenile.
Neonatal multiple sulfatase deficiency is the most severe form of the condition. Symptoms often appear shortly following birth. Damage to the nervous system and abnormalities of the skeleton may occur. Hearing loss, malformation of the heart, and an enlargement of the spleen and liver may also occur. Many of these symptoms worsen over time.
Late-infantile multiple sulfatase deficiency is the most common form of the condition. Cognitive development proceeds normally during early childhood but is succeeded by progressive deterioration of mental ability and movement capability.
Juvenile multiple sulfatase deficiency, the rarest form of the condition, occurs when symptoms appear during mid- to late childhood. The progression and subsequent regression of mental and motor skills is similar to the late-juvenile form but often occurs more slowly.
Multiple sulfatase deficiency may also be known as disorder of conification 13 (DOC13), mucosulfatidosis, or multiple sulfatase deficiency syndrome.
What are the Symptoms of Multiple Sulfatase Deficiency?
Symptoms of multiple sulfatase deficiency vary depending on the form of the condition. Symptoms most commonly begin during the first or second year after a child is born. Some fo the most likely symptoms include:
– Rounded, heavy, and underdefined facial features (often described as “coarse”)
– Deafness or loss of hearing
– Enlarged liver and spleen
– Curvature of the spine (scoliosis)
– Abnormal shape or development of the breast bone
– Dry, scaly, and itchy skin (icthyosis)
– Delayed development
– Impaired speech and motor skills
Life expectancy is also shortened in patients with multiple sulfatase deficiency. Most patients survive only a few years after symptoms appear and a diagnosis can be made. This may vary depending on the rate at which neurological symptoms develop and progress.
What Causes Multiple Sulfatase Deficiency?
Multiple sulfatase deficiency is caused by abnormal or inoperative enzymes known as sulfatase enzymes. These enzymes (known as arylsulfatase A, B, and C, along with 2 steroid sulfatase enzymes, and 4 others) are responsible for the breakdown of mucopolysaccharides in individuals without multiple sulfatase deficiency.
Multiple sulfatase deficiency is a heriditary disorder. It is passed by autosomal recessive genes. This mean that a person must receive copies of the abnormal gene from both parents in order to develop the condition. This means that the risk of a child developing multiple sulfatase deficiency is 25% if both parents are carriers.
How is Multiple sulfatase deficiency diagnosed?
Multiple sulfatase deficiency is challenging because of its genetic cause. Doctors may examine medical history, conduct physical exams, and requests additional tests. Genetic testing, such as enzyme assay, or a variety of molecular genetic tests may be required.
More information on these types of tests may be found here.
How is Multiple Sulfatase Deficiency Treated?
Treatment for multiple sulfatase deficiency currently focuses on the management of symptoms. Orthopedists may be able to help with issues involving spine curvature, and certain emollient ointments may soothe ichthyosis and other skin related symptoms.