Alpha-1 antitrypsin deficiency
An inherited condition that can affect the liver and lungs. Usually diagnosed in early childhood or middle age.
Also called: AATD, A1ATD
What does the name mean? Alpha-1 antitrypsin is the name of a protein. Deficiency means there is not enough of the protein.
The information on this page is for:
- Adults and children with A1ATD. or suspected A1ATD.
- Family, friends, carers, and healthcare professionals.
This information focuses on the causes of A1ATD and how it affects the liver. In adults it can also affect the lungs. You can find more information about this on the Asthma and Lung UK website.
Alpha-1 antitrypsin deficiency is an inherited condition This means it can be passed down in families. It is most common in people with northern European ancestry. But many people are never diagnosed.
It is a lifelong condition, but symptoms usually appear in early childhood or in middle age.
A1ATD affects different people very differently. Some will become very unwell. But most people with A1ATD will stay well and may not even know they have the condition. Babies with A1ATD symptoms usually get better and go on to have normal childhoods.
A1ATD can increase the risk from other liver and lung conditions. This means it is important to avoid risks like smoking, obesity and alcohol.
Use the links below to find more information and support for A1ATD. There is a lot of information here so you can bookmark this page to come back to whenever you need it.
Quick Summary
Alpha-1 antitrypsin deficiency:
- is an inherited condition
- is caused by a problem with a protein made in the liver
- is usually diagnosed in very young children or in middle age
- can range from having no symptoms to being very severe
- can cause liver problems in children
- usually gets better in children
- can cause liver and lung problems in adults
- lung problems are more likely and start earlier in smokers
- is treated at specialist centres
- liver problems are usually treated by managing symptoms
- can sometimes need treatment with a liver transplant
Find out more about alpha-1 antitrypsin deficiency using the links below.
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My child has just been diagnosed with A1ATD - what now?
Treatment for children
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This content was last reviewed: June 2026
Our expert reviewers:
We would like to thank everyone who helped with creating and reviewing this page. Including Dr Bill Griffiths, consultant hepatologist, Cambridge university hospitals, Professor Dino Hadzig, consultant paediatric hepatologist, King’s college hospital, Dr Girish Gupte, consultant paediatric hepatologist, Birmingham children’s hospital. And all our patient and family reviewers.
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