Sanfilippo Syndrome

Sanfilippo Syndrome

What is Sanfilippo syndrome?

Sanfilippo syndrome, also known as Mucopolysaccharidosis type III (MPS III), is a rare inherited genetic condition that mainly affects the brain and nervous system. It can also affect movement, joints, sleep, behaviour and other aspects of physical health.

The condition is caused by the body's inability to break down a complex sugar molecule called heparan sulphate. This happens because one of the enzymes needed to break down the molecule is missing or does not work properly. As heparan sulphate builds up inside cells, it can cause progressive damage, particularly to the brain and nervous system.

Children with Sanfilippo syndrome may initially develop skills in the expected way or experience early developmental delays. Over time, they may experience changes in learning, communication, behaviour, movement and previously acquired skills.

The condition affects everyone differently, and the rate and pattern of progression can vary.

What causes Sanfilippo syndrome?

Sanfilippo syndrome is a genetic condition caused by changes in one of four genes responsible for producing enzymes needed to break down heparan sulphate.

There are four main types:

• Sanfilippo syndrome type A: Caused by changes in the SGSH gene.

• Sanfilippo syndrome type B: Caused by changes in the NAGLU gene.

• Sanfilippo syndrome type C: Caused by changes in the HGSNAT gene.

• Sanfilippo syndrome type D: Caused by changes in the GNS gene.

All four types affect the body's ability to break down heparan sulphate, although the course and severity of the condition can differ.

How is Sanfilippo syndrome inherited?

Sanfilippo syndrome is inherited in an autosomal recessive pattern. This means a child needs to inherit an altered copy of the relevant gene from each parent to develop the condition.

Parents who carry one altered copy of the gene are usually unaffected themselves and may not know they are carriers.

When both parents are carriers of an altered copy of the same relevant gene, each pregnancy has:

• A 25% chance of the child having Sanfilippo syndrome.

• A 50% chance of the child being a carrier.

• A 25% chance of the child inheriting neither altered copy.

Genetic counselling can help families understand inheritance, testing and the implications for future pregnancies.

Who does Sanfilippo syndrome affect?

Sanfilippo syndrome can affect children of any sex. Signs often become noticeable during early childhood, although the timing and presentation vary.

Early signs may include delayed speech, developmental differences, sleep difficulties, behavioural changes or recurrent ear and respiratory infections. As the condition progresses, some children experience a decline in previously acquired skills and increasing difficulties with movement and everyday activities.

The condition is rare, with estimates often placing its occurrence at approximately 1 in 70,000 births. Estimates can vary between populations and studies.

What are the common symptoms of Sanfilippo syndrome?

Sanfilippo syndrome can affect several areas of development and physical health. Not every individual will experience all the symptoms listed below.

Development, learning and communication

• Developmental delay.

• Speech and language difficulties.

• Learning difficulties and progressive intellectual disability.

• Changes in communication and social interaction.

• Loss of previously acquired skills.

Behaviour and sleep

• Hyperactivity, impulsivity or restlessness.

• Anxiety, distress or changes in behaviour.

• Difficulties settling or staying asleep.

• Changes in daily routines and emotional regulation.

Movement and physical function

• Difficulties with balance and coordination.

• Changes in walking pattern or walking ability.

• Reduced mobility and difficulty with everyday movements.

• Joint stiffness and reduced range of movement.

• Changes in muscle tone and posture.

• Scoliosis or other musculoskeletal difficulties in some individuals.

• Increasing difficulty with transfers, standing or maintaining comfortable positions.

Other health concerns

• Seizures.

• Swallowing or feeding difficulties.

• Recurrent ear, nose and throat infections.

• Breathing difficulties or recurrent respiratory problems.

• Diarrhoea or constipation.

• Hearing or vision difficulties.

• Heart-related complications in some individuals.

Some children may also develop physical features such as a prominent forehead, thick eyebrows, a broad nose or a fuller lower lip. These features vary and are not enough on their own to diagnose the condition.

How is Sanfilippo syndrome diagnosed?

Diagnosis usually involves a combination of clinical assessment and specialist testing.

This may include:

• Reviewing developmental history and symptoms.

• Urine or blood tests to investigate the body's processing of complex sugars.

• Enzyme testing to identify the affected enzyme.

• Genetic testing to confirm the specific type of Sanfilippo syndrome.

• Assessments of movement, communication, learning and other areas of health.

A specialist team will help families understand the diagnosis and coordinate ongoing care.

How can physiotherapy help with Sanfilippo syndrome?

Physiotherapy can play an important role in supporting comfort, movement and physical function throughout the course of Sanfilippo syndrome.

Although physiotherapy cannot cure the condition or stop its underlying progression, an individualised programme may help maintain useful movement, support participation in everyday activities and address physical difficulties as they arise.

The focus of physiotherapy may change over time, depending on the individual's abilities, comfort, health and personal goals.

Maintaining movement and joint flexibility

Joint stiffness and reduced movement can affect comfort, positioning and everyday activities.

A physiotherapist may use gentle, individually tailored movement activities and stretching where appropriate to help maintain available range of movement and support comfortable positioning.

Supporting strength and physical function

Activities can be adapted to support the movement and physical abilities a person has at each stage.

This may include carefully selected functional activities, supported movement and appropriate exercises to encourage participation in daily routines.

Exercise intensity should be tailored to the individual. High-intensity or strenuous exercise is not automatically appropriate, particularly where there are additional concerns such as joint problems, reduced bone strength, cardiac complications or fatigue.

Balance, coordination and mobility

Changes in balance, coordination and walking can affect a person's ability to move safely and participate in familiar activities.

Physiotherapy may include:

• Supported standing and walking activities where appropriate.

• Balance and coordination activities.

• Practising transfers and everyday movements.

• Adapting activities to changing mobility.

• Advice on suitable walking aids or other mobility equipment.

Posture, positioning and comfort

As movement and mobility change, maintaining comfortable positions becomes increasingly important.

Physiotherapists can assess posture, seating, positioning and movement to help support comfort and function. They can also identify concerns that may need input from other members of the healthcare team, such as changes in spinal alignment or persistent pain.

Supporting families and carers

Families and carers are central to supporting someone living with Sanfilippo syndrome.

Physiotherapy can provide guidance on safe movement, positioning, transfers, suitable activities and ways to incorporate movement into everyday routines. Advice can be adapted as needs change, helping families feel more confident in supporting comfort and participation.

Could hydrotherapy help someone with Sanfilippo syndrome?

Hydrotherapy involves therapeutic movement and exercise in a pool, with activities adapted to the individual's abilities and clinical needs.

The buoyancy of water can reduce the effects of gravity on the body, making some movements easier to practise. Water also provides resistance, which can be used for carefully selected movement and strengthening activities.

Depending on the individual's needs, hydrotherapy may support:

• Gentle movement and joint mobility.

• Comfortable movement with reduced weight-bearing.

• Balance and coordination activities.

• Supported movement and physical participation.

• Relaxation and enjoyment of movement.

Hydrotherapy is not suitable for everyone. Before starting, the physiotherapist and wider healthcare team should consider factors such as breathing and cardiac health, seizure management, swallowing difficulties, infection risk and the individual's ability to participate safely in the pool.

Water temperature, session length and activity levels should be selected according to the person's needs and clinical assessment.

Specialist equipment at Positive Steps Physiotherapy

At Positive Steps Physiotherapy, specialist equipment may be incorporated into rehabilitation when it is appropriate for the individual's abilities, health and goals.

EzyGain treadmill

The EzyGain treadmill may be used to support walking practice and gait rehabilitation. Where suitable, supported walking can provide opportunities to practise stepping and build confidence with movement.

MOTOmed

The MOTOmed can provide assisted or active repetitive movement of the arms or legs. It may be considered when a person would benefit from supported movement or adapted cycling-style activity.

BlazePods

BlazePods are interactive light-based training devices that can be incorporated into selected activities to encourage reaching, movement, coordination and engagement.

Activities can be adapted to the individual's abilities and understanding.

Hypervibe

The Hypervibe is a whole-body vibration platform that may be considered for selected individuals as part of a wider rehabilitation programme. Its suitability needs careful assessment, particularly where there are concerns about bone strength, joint health or other medical complications.

Not every person will need or be suitable for every piece of equipment. The physiotherapy team will select activities and equipment according to individual needs, comfort, safety and goals.

Our approach at Positive Steps Physiotherapy

At Positive Steps Physiotherapy, we recognise that every person with Sanfilippo syndrome has their own abilities, interests, challenges and support needs.

Our aim is to help individuals and their families make the most of the movement and function available to them, while adapting rehabilitation as needs change.

We take a positive, person-centred approach, creating opportunities for meaningful activities that encourage engagement, comfort and participation.

Our team works alongside families and the wider healthcare team to support consistent care and ensure that rehabilitation is appropriate for the individual's changing needs.

We believe in always finding what can be done and working together to find new ways to thrive.

Goals of physiotherapy for Sanfilippo syndrome

Physiotherapy goals are individualised and may include:

• Maintaining comfortable movement and joint flexibility.

• Supporting physical function for as long as possible.

• Encouraging participation in meaningful activities.

• Supporting mobility, transfers and positioning.

• Addressing balance and coordination difficulties where appropriate.

• Helping manage stiffness, discomfort and positioning needs.

• Supporting families and carers with practical advice.

• Reviewing equipment and adapting activities as needs change.

• Promoting comfort, dignity and quality of life.

The priorities may change as the condition progresses. Physiotherapy should always be guided by the person's needs, comfort, safety and overall care plan.

How Positive Steps Physiotherapy can help

Living with Sanfilippo syndrome can bring changing physical and practical challenges for individuals and their families. Physiotherapy can provide ongoing support focused on movement, comfort, participation and quality of life.

At Positive Steps Physiotherapy, we tailor our approach to each individual, working with families and the wider healthcare team to identify appropriate goals and adapt support over time.

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