What are immune-mediated inflammatory diseases?

Immune-mediated inflammatory diseases (IMIDs) are common medical conditions which can cause a great deal of pain, distress, loss of function and, in some cases, early death in those affected by them. It is difficult to know the precise number of people in the UK affected by such diseases, however we know that rheumatoid arthritis affects roughly 700,000 people and lupus up to 50,000 people.

 IMIDs are clinically diverse, for example, rheumatoid arthritis (RA) affects joints whilst psoriasis targets skin, systemic lupus erythematosus (SLE) may affect the kidneys and the skin, as well as the heart, lungs and brain. Autoimmune hepatitis and primary biliary cirrhosis both cause damage to the liver and Sjögren's syndrome can stop moisture-secreting glands working - meaning those affected have dry eyes and mouth amongst other symptoms. Despite these differences, many of these diseases share the similar genetic & environmental factors and inflammatory mechanisms.

Although we can say that the treatment of a significant proportion of people with IMIDs has been revolutionised through the use of biologic drugs and more informed treatment strategies, some patients still show no response to therapies that work for others or develop resistance to the treatments over time.

A more precise approach that treats the right patient, with the right drug at the right dose and time is essential. This is only possible through in-depth study of large datasets derived from patients affected by IMIDs. By analysing detailed information about individual patients and their samples, researchers can produce a "molecular map" that would allow their clinician to develop a more informed treatment plan which will provide a better outcome for that individual with reduced risks. So far much of the research in IMIDs have focused on one disease at a time, rather than reviewing the data for groups of diseases known to share similar genetic pathways or environmental risks.

You can find out more about the diseases studied in IMID-Bio-UK by clicking on the accordion below.


Disease Summary

 There are many different diseases which are classed as immune-mediated inflammatory disease.  In the first instance we are focusing on the diseases listed below.  We have given short and simplistic explanations of each disease, however, in reality they are much more complicated and the impact of the disease on the person affected and their immediate friends and family shouldn't be underestimated.


Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a long-term condition in which painful inflammation of joints.  If left untreated to can lead to joint damage and disability. It affects approximately 1% of adults.  Whilst it is more common in older adults, it is known to affect people of any age.  For most patients, the earlier effective treatment is introduced, the better the control of joint inflammation and the less likely patients are to develop permanent joint damage. Whilst a number of treatments are available for RA, none of which are guaranteed to work for every patient and there is no way of telling which treatment will work best for which person prior to treatment.


Systemic Lupus Erythematosus (SLE) is a chronic autoimmune disease affecting approximately 16,000 people in the UK where the body’s own immune system to turn against itself and attack healthy tissue.  Symptoms vary between people and in severity.  Common symptoms include painful and swollen joints, fever, chest pain, hair loss, mouth ulcers, swollen lymph nodes, feeling tired, and a red rash which is most commonly on the face. Often there are periods of illness, called flares, and periods of remission during which there are few symptoms.

Primary Biliary Cholangitis

Primary Biliary Cholangitis (PBC). PBC affects up to 20,000 people in the UK and whereas many do well with current therapy an important group of people have more aggressive liver disease that can lead to liver failure and the need for a liver transplant or other significant long-term complications.  

Primary Sjögren's Syndrome

Primary Sjögren's Syndrome (pSS) is a chronic autoimmune disease characterised by a range of symptoms including dryness, fatigue, depression, anxiety, pain and an increased risk of lymphoma.  UKPSSR aims to facilitate clinical trials and academic research studies in order to improve our understanding of what causes Primary Sjögren's Syndrome and to find better, more effective treatment for people with this condition.


Psoriasis is a common, chronic, potentially disfiguring disease that affects more than 1 million people in the UK. It can cause considerable psychological and social disability. Psoriasis can occur on any area of the body, at any age. There are various types of psoriasis, and different ways of treating psoriasis on different areas of the body.

Autoimmune Hepatitis

Autoimmune hepatitis is an inflammatory liver disease affecting up to 10,000 people in the UK. Despite well-established therapies, there are some patients who do not respond adequately to therapy or who suffer significant side effects from treatment.