Type III - Sanfilippo syndrome

The most frequent type of mucopolysaccharidosis in Poland.

It is a progressive, multiorgan disease inherited in the autosomal recessive manner. The defective gene is passed along to a child by a healthy mother and father. The defective gene causes that the child's body does not receive information concerning the enzyme structure. The chances of having a child affected by Sanfilippo syndrome is about 25%. The chances that siblings will also be affected are 2out of three.

There are four subtypes of this disorder

Type A – caused by the missing or deficient enzyme heparan N-sulfatase

Type B – caused by the missing or deficient enzyme alpha-N-acetylglucosaminidase

Type C – caused by the missing or altered enzyme acetyl-CoAlpha-glucosaminideacetyltransferase

Type D – caused by the missing or deficient enzyme N-acetylglucosamine 6-sulfatase

Between ages 2 and 6 there the affected children show signs of mental and motor regression. These are the main symptoms of the disorder. The initial clinical symptoms are changes in behaviour. The children may suffer from behavioural disorders, emotional issues, psychological and motor development delay, hyperactivity with autism symptoms.

In the early school days the symptoms become more and more acute and a child may have problems with concentration and progressive dementia. Their mental development may be delayed and they may find it more and more difficult to articulate and walk. Eventually they are unable to walk and their lives become confined to the four walls of their room. Parental care is limited to exhausting physical assistance. Children affected by Sanfilippo do not live into adulthood.


Currently there is no replacement therapy for this disorder. Lately the first method of combating the disease has been developed by a distinguished biochemist from the University of Gdansk, professor Grzegorz Węgrzyn. Unfortunately there are no funds indispensable to continue research, clinical trials and experiments.

The difficulty in finding appropriate treatment lies in the fact that it is a neurodegenerative disease – most alterations take place mainly in the brain. The brain is protected by a natural blood-brain barrier, which stops germs, toxic substances but also medicines and in this particular case the missing enzyme.

More information to be found on the following website:


© Przemysław Racinowski