Marinesco–Sjögren syndrome
Encyclopedia
Presentation
The syndrome causes cerebellar ataxiaAtaxia
Ataxia is a neurological sign and symptom that consists of gross lack of coordination of muscle movements. Ataxia is a non-specific clinical manifestation implying dysfunction of the parts of the nervous system that coordinate movement, such as the cerebellum...
(balance and coordination problems), mental retardation, congenital cataracts in early childhood, muscle weakness, inability to chew food, thin brittle fingernails, and sparse hair..
Small stature, mild to severe mental retardation and dysarthria
Dysarthria
Dysarthria is a motor speech disorder resulting from neurological injury of the motor component of the motor-speech system and is characterized by poor articulation of phonemes...
(slow, imprecise speech) are usually present.
Various skeletal abnormalities (e.g., curvature of the spine) and hypergonadotropic hypogonadism
Hypogonadism
Hypogonadism is a medical term for decreased functional activity of the gonads. Low testosterone is caused by a decline or deficiency in gonadal production of testosterone in males...
often occur.
Muscle weakness is progressive, but life expectancy is near normal.
Diagnosis
Diagnosis of MSS is based on clinical symptoms, magnetic resonance imagingMagnetic resonance imaging
Magnetic resonance imaging , nuclear magnetic resonance imaging , or magnetic resonance tomography is a medical imaging technique used in radiology to visualize detailed internal structures...
(MRI) of the brain (cerebellar atrophy particularly involving the cerebellar vermis
Cerebellar vermis
The cerebellar vermis is located in the medial, cortico-nuclear zone of the cerebellum, residing in the posterior fossa of the cranium. The primary fissure in the vermis curves ventrolaterally to the superior surface of the cerebellum, dividing it into anterior and posterior lobes....
), and muscle biopsy
Muscle biopsy
In medicine, a muscle biopsy is a procedure in which a piece of muscle tissue is removed from an organism and examined microscopically. A biopsy needle is usually inserted into a muscle, wherein a small amount of tissue remains. Alternatively, an "open biopsy" can be performed by obtaining the...
.
It can be associated with mutations of the SIL1
SIL1
Nucleotide exchange factor SIL1 is a protein that in humans is encoded by the SIL1 gene.-Interactions:SIL1 has been shown to interact with Binding immunoglobulin protein.-External links:* -Further reading:...
gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
, and a mutation can be found in about 50% of cases.
Differential diagnosis includes Congenital Cataracts Facial Dysmorphism Neuropathy (CCFDN), Marinesco-Sjögren like syndrome with chylomicronemia, carbohydrate deficient glycoprotein
Glycoprotein
Glycoproteins are proteins that contain oligosaccharide chains covalently attached to polypeptide side-chains. The carbohydrate is attached to the protein in a cotranslational or posttranslational modification. This process is known as glycosylation. In proteins that have segments extending...
syndromes, Lowe syndrome, and mitochondrial disease
Mitochondrial disease
Mitochondrial diseases are a group of disorders caused by dysfunctional mitochondria, the organelles that are the "powerhouses" of the cell. Mitochondria are found in every cell of the human body except red blood cells...
.
Treatment
Treatment for MSS is symptomatic and supportive including physical and occupational therapy, speech therapy, and special education. CataractCataract
A cataract is a clouding that develops in the crystalline lens of the eye or in its envelope, varying in degree from slight to complete opacity and obstructing the passage of light...
s must be removed when vision is impaired, generally in the first decade of life. Hormone replacement therapy is needed if hypogonadism
Hypogonadism
Hypogonadism is a medical term for decreased functional activity of the gonads. Low testosterone is caused by a decline or deficiency in gonadal production of testosterone in males...
is present.