What is Sanfilippo Syndrome?

Sanfilippo is a rare genetic condition that causes fatal brain damage. It is a type of childhood dementia and most patients never reach adulthood. But there is hope. Researchers around the world are working hard to find effective treatments.


A rare metabolic disorder

Sanfilippo is considered a rare disease: 1 in 70,000 children are born with the inherited condition. The exact prevalence is not known, but it is estimated that there are between 75 and 100 children living with Sanfilippo in Australia.

Sanfilippo is a metabolic disorder which means there is a problem with one of the chemical reactions that naturally occurs in the body. It is caused by a lack of an enzyme that normally breaks down and recycles a large, complex sugar molecule called 'heparan sulphate'.  

The disease has four subtypes (A, B, C and D). Each subtype corresponds to a lack of a different enzyme, each one responsible for a different step of breaking down heparan sulphate.

Sanfilippo is also sometimes referred to as a lysosomal storage disease or LSD, because the heparan sulphate is stored in a part of the cell called the lysosome. It also belongs to a group of diseases called Mucopolysaccharidoses (MPS) all of which involve the abnormal accumulation of complex sugars (called mucopolysaccharides or glycosaminoglycans 'GAGs'). Another name for Sanfilippo is Mucopolysaccharidoses type III or MPS III.

A form of childhood dementia

Sanfilippo mostly affects the brain and is one of a group of conditions called 'childhood dementia'. Over time, brain cells fill up with waste that the body is unable to process. As the brain gets progressively damaged, children experience severe hyperactivity, disordered sleep, loss of speech, cognitive decline, cardiac issues, seizures, loss of mobility, and finally death, usually before adulthood.

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There is currently no treatment or cure available to children diagnosed with this devastating disease. Researchers around the world are working hard to develop effective treatments, with several clinical trials already completed or underway.

Amongst the therapeutic avenues being explored, currently gene therapy is the most promising. However, a combination of treatments is likely to give the best outcome, so it is important that a wide variety of approaches continue to be researched. 

Research towards a cure for Sanfilippo may contribute to the development of treatments for more common neurodegenerative disorders like Alzheimer’s and Parkinson’s diseases.

Read more about Sanfilippo Therapy Avenues


Further information