Health condition
Mucopolysaccharidoses in adults
The mucopolysaccharidoses (MPS) are inherited enzyme deficiencies in which complex sugars accumulate in tissues; attenuated forms can reach adulthood undiagnosed with joint, heart valve, airway and eye problems.
Why trust this guide
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Editorial team
Written by our editorial team from the UK sources listed on each page.
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Sourced from guidance
Checked against current NHS and UK specialist society guidance at the time of review.
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Current for 2026
Reviewed on 2026-09-27 with the next review scheduled for 2027-09-27.
Key facts
The essentials at a glance.
Which gene and test confirm it, who should be tested in the family, and which specialist to see.
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A family of disorders (MPS I, II, IV, VI and others), each caused by a different enzyme gene
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Attenuated MPS I (Scheie) and MPS IV can present with stiff joints, carpal tunnel syndrome at a young age, corneal clouding, heart valve disease or hip problems
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Diagnosis: urinary glycosaminoglycans, enzyme assays and genetic testing
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Enzyme replacement therapy exists for several types - adults need coordinated multi-specialty surveillance
Understanding the condition
What it is and what happens next.
What causes it, how it is confirmed, and the testing and specialist routes available in the UK.
What it is and how it presents
Severe MPS presents in childhood, but milder enzyme deficiencies allow slow accumulation over decades, producing an adult with unusually stiff hands, bilateral carpal tunnel syndrome in their twenties, cloudy corneas, aortic or mitral valve thickening, or hip dysplasia that keeps being treated as simple orthopaedic wear. Height is often normal in attenuated disease and intelligence unaffected, so nothing flags the underlying diagnosis unless someone thinks of it.
Testing, surveillance and specialist care
Screening starts with urinary glycosaminoglycans, followed by targeted enzyme assays and gene sequencing to identify the exact type, which determines whether enzyme replacement therapy is available. Adults are best managed through a specialist metabolic centre coordinating cardiology, ophthalmology, orthopaedic and airway surveillance, with genetic counselling for the family. NHS clinical genetics services carry some of the longest waits in the health service, often many months for a first appointment, whereas private genetic testing and a specialist review can typically be arranged within around two weeks.
Seeing a specialist
Who to see, and how quickly you can be seen.
The specialist for this condition is usually a metabolic physician (inherited metabolic disease clinic). Your GP can refer you on the NHS, or you can arrange a private consultation directly.
A quiet reminder
This guide is for information, not medical advice.
Your GP knows your history and can tell you which parts apply to you. If in doubt, see them - and seek urgent care for any emergency symptoms.
Frequently asked
Common questions about Mucopolysaccharidoses in adults.
Quick, plain-English answers to what people ask us most.
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What are mucopolysaccharidoses in adults?
Mucopolysaccharidoses, or MPS disorders, are a group of rare inherited metabolic conditions in which the body cannot properly break down certain complex sugars, causing them to build up in cells and progressively damage multiple organs. Some forms allow survival into adulthood with milder features.
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What causes mucopolysaccharidoses?
MPS disorders are caused by inherited deficiencies in specific enzymes needed to break down glycosaminoglycans, complex sugar molecules found throughout the body's connective tissues. Most types are inherited in an autosomal recessive pattern.
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What symptoms do adults with MPS experience?
Adults with milder MPS variants can have joint stiffness, reduced mobility, hearing loss, heart valve problems, corneal clouding affecting vision, and in some types, mild to moderate cognitive effects, with the specific pattern depending on the MPS subtype.
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Is mucopolysaccharidosis hereditary?
Yes, MPS disorders are genetic conditions, most inherited in an autosomal recessive pattern, meaning both parents carry one copy of the faulty gene without symptoms themselves, except for MPS type II, which is X-linked.
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Can mucopolysaccharidoses be cured?
There's no cure, but enzyme replacement therapy is available for several MPS subtypes and can significantly slow disease progression and improve certain symptoms, particularly when started before irreversible organ damage occurs.
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How are mucopolysaccharidoses managed in adulthood?
Management involves a multidisciplinary team addressing joint, cardiac, respiratory, hearing and vision problems, alongside enzyme replacement therapy where available, and regular monitoring for disease progression across affected organ systems.
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When should an adult with suspected undiagnosed MPS seek specialist assessment, and how quickly can this be arranged privately?
Seek specialist metabolic assessment if you have a combination of unexplained joint stiffness, hearing loss, corneal clouding and heart valve problems, particularly with a relevant family history. A private metabolic specialist can typically arrange initial assessment within about two weeks.