Hurler Syndrome | MPS-1H – Hurler Syndrome

Hurler Syndrome (MPS I-H) Trusted, science based information and support

Hurler syndrome, also called MPS I-H, is a rare, inherited lysosomal storage disorder that affects the brain, bones, heart, lungs and other organs. Early diagnosis and timely treatment can change the course of the disease, but many children still live with a significant long term burden

Clear explanations for families, patients and healthcare professionals
Up to date information on diagnosis, HSCT, ERT and emerging gene therapy research
Practical guidance for day to day life with Hurler syndrome
Ways to support research and education for this rare condition

What is Hurler syndrome (MPS I-H)?

Hurler syndrome, or mucopolysaccharidosis type I-H (MPS I-H), is the most severe form of MPS I, a rare genetic condition caused by a deficiency of the enzyme alpha L iduronidase (IDUA). Without enough IDUA, glycosaminoglycans (GAGs) build up inside lysosomes and gradually damage many organs, including the brain, bones, heart, lungs, eyes, liver and spleen.

Signs often appear in the first year of life. Babies may look well at birth, then slowly develop coarse facial features, hernias, frequent chest or ear infections and stiffness of joints. Without treatment, Hurler syndrome leads to progressive developmental decline and life limiting complications in early childhood.

Although Hurler syndrome is rare, the impact on children and families is profound. This site brings together medical knowledge, practical guidance and lived experience, so that families, clinicians and researchers can work together to improve outcomes.

Quick Links

Overview of Hurler syndrome

Learn how MPS I-H affects the body

Symptoms and early signs

What to look for in babies and children

How Hurler syndrome is diagnosed

Enzyme tests, genetic testing and assessments

For families: start here

A diagnosis of Hurler syndrome can feel overwhelming. You may be searching for clear explanations, practical advice and honest answers about what happens next. These pages are written in plain language and reviewed by clinicians and families who know MPS I-H well.

Newly diagnosed

First questions to ask, understanding test results, preparing for specialist appointments.

Treatments and hospital care

What HSCT, enzyme replacement therapy (ERT) and supportive treatments involve, and how they fit together.

Everyday life with Hurler syndrome

Mobility, schooling, emotional wellbeing, siblings, financial support and planning ahead.

Medical note All information on this site is for general education only and does not replace advice from your own medical team.

Treatments for Hurler syndrome today

The current standard of care for children with Hurler syndrome is early haematopoietic stem cell transplantation (HSCT), often combined with enzyme replacement therapy (ERT) before and after transplant. HSCT can preserve neurocognitive function and improve survival when performed in the first years of life, while ERT can help reduce GAG levels and support organ function.

Supportive care is equally important. Children need coordinated input from many specialists, including cardiology, respiratory medicine, orthopaedics, neurology, ENT, ophthalmology, dentistry, physiotherapy and occupational therapy. Even with excellent care, many patients live with ongoing skeletal problems, airway challenges, pain and fatigue, so long term follow up is essential.

Haematopoietic stem cell transplant (HSCT)

What to expect before, during and after transplant

Enzyme replacement therapy (ERT)

How ERT works, infusions and monitoring

Supportive and symptom based care

Managing breathing, heart health, bones, pain and sleep

Long term outcomes after treatment

What we know from long term follow up studies

Why research into Hurler syndrome matters

Over the last three decades, early HSCT and ERT have transformed survival for many children with Hurler syndrome. However, long term studies show that even successfully transplanted patients can experience ongoing bone disease, joint stiffness, airway problems, heart valve disease and other complications that affect quality of life into adolescence and adulthood.

Because IDUA deficiency affects every organ where GAGs accumulate, researchers around the world are working on new ways to deliver enzyme or gene based treatments more effectively to the brain, skeleton and other hard to reach tissues. Approaches being studied include ex vivo and in vivo gene therapy using lentiviral and AAV vectors, improved transplant strategies and combination therapies.

For families, this research brings both hope and complexity. Our aim is to explain the science clearly, highlight what is already known and what is still experimental, and help families ask informed questions when considering clinical trials.

Research hub

Explore the science of MPS I-H, current standard of care and future therapies

Gene therapy in Hurler syndrome

How gene therapy aims to correct IDUA deficiency at its source

Important note All therapies discussed in the research sections that are described as gene therapy or investigational are at preclinical or clinical trial stages and are not approved treatments outside regulated studies.

You are not alone

Living with Hurler syndrome affects the whole family. Connecting with other parents, carers and adults living with MPS I-H can provide emotional support, practical tips and a sense of community.

Find support organisations

Links to trusted MPS and rare disease charities in your region.

Support groups and communities

Online and local groups where families share experience and advice.

Patient and family stories

Real stories from people living with Hurler syndrome at different ages.

If you would like to share your story to help other families, please
contact us

Support in Hurler syndrome

Support education and research in Hurler syndrome

Because Hurler syndrome is a rare genetic disorder, progress depends on sustained support for reliable education, long-term follow-up and independent research.

Every contribution, large or small, helps move the field forward.