Danon disease

What is Danon disease?

Danon disease is a lysosomal storage disorder. Your body is made up of trillions of individual cells and each cell contains a small part called the lysosome. This is primarily responsible for breaking down and recycling worn out cell components. Inside the lysosome are enzymes which perform this very important housekeeping role. In Danon disease the worn out cell components cannot reach the lysosome and are not broken down completely allowing multiple products to build up and become stored in very specific areas of your body. There are many different enzymes in your lysosomes, and deficiencies of each enzyme or other lysosomal related protein will cause a different disease. All of these different diseases together are called lysosomal storage disorders.

How will this affect me?

In Danon disease the cells most commonly affected can be found in the heart and muscles.

This means you may experience or be at risk of the following:

• Heart rhythm disturbance
• Heart failure
• Difficulty with walking
• Increased stress on the heart
• Fatigue
• Anxiety

The progress of the disease in adults is extremely variable with some people not really noticing any symptoms whilst others are more severely affected.

If you have any questions about the effects and progression of the disease please do ask your doctor or specialist nurse.

Is there any treatment?

At the moment there is no specific treatment for Danon available on the NHS in the UK. We work very closely with colleagues from around the world to keep up to date/participate in research in this field.

How did I get Danon disease?

Danon disease is a genetic condition which means that you inherited it from your parents. There are instructions in your genes for making lysosomal enzymes and other related proteins, and a small change in your DNA can be enough to stop the necessary protein from working properly. You have two copies of every gene, having received one from each parent.

There are two specific chromosomes that determine whether you are male or female – males are XY and females are XX. In Danon disease the DNA change is found on the X chromosome.

If you are male and have an X chromosome that carries the DNA change you will have the disorder because you do not have another X chromosome that could take over

If you are female and have an X chromosome that carries the DNA change you may have some symptoms of the disorder although generally not as severely because your other X chromosome can make effective enzyme.

Please do talk to your doctor or specialist nurse who can explain this in more detail.

What do I need to do next?

• Do ask your doctor or nurse for more information.
• Do attend your regular appointments with the lysosomal disorders team so that we can ensure you receive the most appropriate care and can keep you informed of any new developments.
• Do maintain a healthy lifestyle
  • avoid smoking
  • keep alcohol consumption to a minimum
  • maintain a healthy weight
  • take some regular exercise

You may find it helpful to contact your patient support group

Metabolic support UK

Tel: 0845 241 2173

Metabolic Support UK (opens in a new tab)

Contact us

LDU Box 135, Addenbrooke’s Hospital, Hills Road, Cambridge. CB2 0QQ

Tel: 01223 274634

Email LDU Cambridge

CUH Website - Lysosomal disorders

Please note the department is open Monday to Friday 08:30-17:00.

If you are unwell outside of these hours you should seek medical advice from your local healthcare team.

If your emergency doctor needs specific advice they should call the hospital switchboard on 01223 245151 and ask for the metabolic consultant on call.