Autoimmune Diseases: Types, Symptoms, Causes, Diagnosis, Treatment and More

Autoimmune diseases can be confusing because they do not always look like a single illness. One person may experience persistent joint pain and stiffness, another may have unexplained fatigue and skin changes, while someone else may develop digestive problems, muscle weakness or changes in blood sugar.

What connects these conditions is the immune system. Normally, your immune system protects you from infections and other harmful substances. In an autoimmune disease, the immune system mistakenly attacks healthy cells, tissues or organs. More than 80 autoimmune diseases are recognised, while some medical sources describe more than 100 autoimmune or immune-mediated conditions.

The good news is that many autoimmune diseases can be effectively managed. Although most cannot currently be cured, appropriate treatment can reduce inflammation, prevent organ damage, control symptoms and help people maintain a fulfilling, active life.

What are autoimmune diseases?

Autoimmune diseases are conditions in which the immune system mistakenly identifies part of the body’s own tissues as a threat and launches an immune response against them.

The affected part of the body depends on the particular disease. Autoimmune conditions can affect the:

• Joints
• Skin
• Thyroid gland
• Pancreas
• Digestive system
• Blood vessels
• Muscles
• Nervous system
• Kidneys
• Liver
• Blood cells
• Multiple organs at the same time

For example, rheumatoid arthritis primarily affects the joints, Hashimoto’s disease affects the thyroid, type 1 diabetes damages insulin-producing pancreatic beta cells, and multiple sclerosis affects the central nervous system.

Some autoimmune diseases are organ-specific, while others, such as lupus and systemic sclerosis, can affect several parts of the body.

What are the 10 most common autoimmune diseases?

There is no universally accepted ranking of autoimmune diseases by prevalence because figures vary between countries and because some conditions are classified as autoimmune while others are more accurately described as immune-mediated.

Some of the most commonly recognised autoimmune or immune-mediated diseases include:

1. Hashimoto’s thyroiditis – The immune system attacks the thyroid and may eventually cause hypothyroidism.
2. Rheumatoid arthritis – Causes inflammation, pain and stiffness, particularly in the joints.
3. Psoriasis and psoriatic arthritis – Affect the skin and, in some people, the joints.
4. Type 1 diabetes – The immune system attacks insulin-producing cells in the pancreas.
5. Celiac disease – An immune reaction to gluten damages the small intestine.
6. Graves’ disease – Causes the immune system to overstimulate the thyroid.
7. Systemic lupus erythematosus (lupus) – Can affect the skin, joints, kidneys, blood, brain and other organs.
8. Inflammatory bowel disease (IBD) – Includes Crohn’s disease and ulcerative colitis.
9. Multiple sclerosis (MS) – An immune-mediated disease affecting the central nervous system.
10. Sjögren’s syndrome – Commonly affects the glands responsible for producing tears and saliva.

Cleveland Clinic and other major medical references note that autoimmune diseases can affect almost any body system, which explains the considerable variation in symptoms.

What are the top 20 autoimmune diseases?

If you are looking for a broader list, the following 20 conditions are among the better-known autoimmune or immune-mediated diseases:

1. Rheumatoid arthritis
2. Systemic lupus erythematosus (lupus)
3. Hashimoto’s thyroiditis
4. Graves’ disease
5. Type 1 diabetes
6. Celiac disease
7. Multiple sclerosis
8. Psoriasis
9. Psoriatic arthritis
10. Sjögren’s syndrome
11. Crohn’s disease
12. Ulcerative colitis
13. Addison’s disease
14. Myasthenia gravis
15. Systemic sclerosis (scleroderma)
16. Autoimmune hepatitis
17. Pernicious anemia
18. Vitiligo
19. Autoimmune vasculitis
20. Inflammatory myositis, including dermatomyositis and polymyositis

Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy (CIDP) are also immune-mediated neurological disorders that are sometimes included in broader lists of autoimmune diseases.

The classification of certain conditions can vary between medical sources, so a “top 20” list should not be interpreted as an official medical ranking.

What are the first signs of autoimmune disease?

The early symptoms can be subtle and may resemble many other health conditions.

Common warning signs include:

• Persistent or unexplained fatigue
• Joint pain or swelling
• Morning stiffness
• Recurrent low-grade fever
• Muscle aches or weakness
• Skin rashes
• Hair loss
• Unexplained weight changes
• Numbness or tingling
• Digestive problems
• Recurrent mouth ulcers
• Dry eyes or dry mouth
• Sensitivity to cold
• Changes in bowel habits
• Unexplained anaemia
• Difficulty concentrating

These symptoms do not automatically mean that someone has an autoimmune disease. Fatigue, joint pain and rashes, for example, can occur with infections, nutritional deficiencies, hormonal disorders and many other conditions.

What raises suspicion is a persistent or recurring pattern, particularly when several symptoms occur together. Common symptoms reported across autoimmune diseases include fatigue, fever, malaise, joint pain and rashes.

What causes autoimmune diseases?

There is no single cause of autoimmune disease. Researchers believe that autoimmune disorders usually develop through a complicated interaction between genetic susceptibility and environmental factors.

Potential contributors include:

• Family history and genetic factors
• Certain infections
• Smoking
• Environmental chemical exposure
• Hormonal influences
• Ultraviolet exposure in some diseases
• Certain medications in specific circumstances
• Changes in the gut microbiome
• Obesity and metabolic factors
• Other immune or inflammatory conditions

NIEHS research indicates that environmental exposures can interact with genetic susceptibility in the development of autoimmune disease. Smoking and certain occupational exposures, including crystalline silica and some solvents, have also been associated with autoimmune risk.

Importantly, having a genetic predisposition does not mean that a person will definitely develop an autoimmune disease.

Can stress trigger autoimmune diseases?

Stress may contribute to autoimmune disease activity, but it is not considered the sole cause of autoimmune disease.

Psychological stress affects several systems in the body, including the nervous, endocrine and immune systems. Research is increasingly examining whether significant or prolonged psychological stress can influence the development or worsening of certain autoimmune disorders.

Recent NIEHS-supported research has investigated associations between stressful life events and systemic autoimmune rheumatic diseases.

For someone who already has an autoimmune disease, stress may also coincide with worsening symptoms or flares.

However, it would be misleading to tell someone that their autoimmune disease was simply “caused by stress.” Autoimmune disease is much more complex.

How to test for autoimmune disease?

There is no single blood test that can detect every autoimmune disease.

Diagnosis generally begins with a medical history and physical examination, followed by investigations based on the person’s symptoms.

Common tests may include:

Antinuclear antibody (ANA) test

ANA testing is commonly used when conditions such as lupus or other connective-tissue diseases are suspected.

However, a positive ANA does not automatically mean that someone has an autoimmune disease. Some healthy people can have a positive ANA.

Autoantibody tests

Depending on the suspected condition, a doctor may request tests such as:

• Anti-dsDNA
• ENA antibodies
• Anti-CCP
• Rheumatoid factor
• Thyroid antibodies
• Anti-tTG antibodies for celiac disease
• Other disease-specific antibodies

Inflammation tests

ESR and CRP can provide information about inflammation, although they cannot by themselves identify a particular autoimmune disease.

Other blood and urine tests

A doctor may also request:

• Complete blood count (CBC)
• Liver function tests
• Kidney function tests
• Blood glucose
• Thyroid function tests
• Urinalysis
• Complement levels

Imaging such as ultrasound, X-ray, CT or MRI may be required for some conditions. MedlinePlus and Cleveland Clinic both emphasise that autoimmune diagnosis generally combines symptoms, examination and appropriate laboratory or imaging investigations rather than relying on one test.

Which autoimmune disease is serious?

There is no single “most serious” autoimmune disease because severity varies considerably between individuals.

An autoimmune disease becomes particularly concerning when it causes significant or permanent damage to vital organs.

Examples of potentially serious autoimmune conditions include:

• Systemic lupus erythematosus
• Systemic sclerosis
• Severe autoimmune vasculitis
• Multiple sclerosis
• Inflammatory myositis
• Autoimmune hepatitis
• Severe myasthenia gravis
• Autoimmune diseases affecting the kidneys, heart, lungs or brain

Some rare autoimmune diseases can be life-threatening. For example, giant cell myocarditis is a rare autoimmune condition that can cause severe heart failure.

The important point is that the severity of the disease in an individual is more important than the name of the condition alone.

What are the top 5 worst autoimmune diseases?

There is no medically recognised list of the “five worst” autoimmune diseases. Autoimmune conditions should not be ranked simply by how painful they are because severity depends on the organs involved, complications and response to treatment.

Nevertheless, conditions that can potentially cause serious organ damage include:

1. Systemic lupus erythematosus – May affect the kidneys, brain, heart, lungs and blood.
2. Systemic sclerosis – Can cause significant skin, lung, kidney and gastrointestinal complications.
3. Severe autoimmune vasculitis – Can damage blood vessels and organs.
4. Multiple sclerosis – May cause progressive neurological disability in some people.
5. Inflammatory myositis – Severe forms can affect muscles as well as swallowing and breathing.

This does not mean that everyone diagnosed with these diseases will develop severe complications. Early diagnosis and modern treatment have substantially improved disease management for many patients.

What’s the most painful autoimmune disease?

There is no scientifically established “most painful” autoimmune disease.

Pain varies significantly between people. Rheumatoid arthritis can cause severe joint pain and stiffness, while lupus, psoriatic arthritis, inflammatory myositis and some vasculitic disorders can also cause substantial pain.

In some autoimmune diseases, the pain is caused by inflammation. In others, nerve involvement or tissue damage may contribute.

Pain intensity also does not necessarily indicate how dangerous the disease is. A condition can cause considerable pain without causing major organ damage, while another condition may silently damage the kidneys, lungs or other organs with relatively few symptoms.

Can I live a normal life with autoimmune disease?

Yes. Many people with autoimmune disease live long, active and fulfilling lives.

The experience varies according to the condition and its severity. Some people have relatively mild disease with occasional flares, while others require long-term treatment and regular monitoring.

Successful management usually involves:

• Taking prescribed medicines consistently
• Attending follow-up appointments
• Monitoring disease activity
• Maintaining appropriate physical activity
• Eating a balanced diet
• Getting adequate sleep
• Managing stress
• Avoiding smoking
• Keeping vaccinations and preventive healthcare up to date where appropriate

Most autoimmune diseases are chronic, but many can be controlled effectively. Some patients experience periods of remission when symptoms become minimal or disappear for a time. Remission, however, is not necessarily the same as a permanent cure.

Can autoimmune disease be cured?

Most autoimmune diseases currently cannot be permanently cured.

However, “not curable” does not mean “not treatable.”

Modern treatment can often:

• Reduce inflammation
• Suppress abnormal immune activity
• Relieve pain
• Prevent organ damage
• Reduce disease flares
• Improve quality of life
• Produce remission

Some autoimmune conditions require replacement of substances that the body can no longer produce. For example, people with type 1 diabetes need insulin, while some people with autoimmune thyroid disease require thyroid hormone replacement.

The goal is therefore usually long-term disease control rather than a quick cure.

What medications treat autoimmune diseases?

Treatment depends entirely on the autoimmune disease, affected organs and severity.

Doctors may use:

• Corticosteroids to rapidly reduce inflammation
• NSAIDs for pain and inflammation in selected conditions
• Conventional immunosuppressants, such as methotrexate, azathioprine or mycophenolate
• Biologic medicines that target specific immune pathways
• Targeted synthetic medicines, including certain JAK inhibitors
• IVIG for selected immune-mediated conditions
• Disease-specific replacement therapy, such as insulin or thyroid hormone

For example, rheumatoid arthritis may be treated with disease-modifying antirheumatic drugs and biologics, whereas multiple sclerosis has its own group of disease-modifying therapies.

Medication should always be selected and monitored by a qualified doctor. Immunosuppressive medicines can increase susceptibility to infections and may have significant side effects.

What is the best diet for autoimmune disease?

There is no single autoimmune diet that works for every autoimmune condition.

A sensible starting point is a balanced, minimally processed eating pattern containing:

• Vegetables and fruits
• Whole grains where tolerated
• Pulses and legumes where appropriate
• Nuts and seeds
• Fish and other lean protein sources
• Healthy unsaturated fats
• Adequate fibre
• Sufficient water

A Mediterranean-style dietary pattern is often considered a useful model because it emphasises vegetables, fruits, whole grains, legumes, fish, nuts and unsaturated fats.

Recent systematic reviews suggest that a Mediterranean diet may improve some quality-of-life and inflammation-related outcomes in certain autoimmune diseases, although the overall evidence remains limited and inconsistent.

Some autoimmune diseases require specific dietary restrictions. For example, people with celiac disease need a strict gluten-free diet.

It is generally better to avoid unnecessarily restrictive diets unless there is a clear medical reason.

How to control autoimmune disease naturally?

Lifestyle measures can support medical treatment, but they should not replace prescribed therapy.

Helpful habits include:

1. Eat a nutrient-rich, balanced diet.
2. Exercise regularly according to your condition and physical ability.
3. Maintain a healthy body weight.
4. Get adequate sleep.
5. Manage chronic stress.
6. Avoid smoking.
7. Limit excessive alcohol consumption.
8. Treat nutritional deficiencies when confirmed.
9. Follow your treatment plan.
10. Attend regular medical reviews.

Be cautious with “natural cures” marketed online. Supplements and herbal products can interact with medicines, and there is no proven natural treatment that cures autoimmune diseases.

At what age do autoimmune diseases start?

Autoimmune diseases can develop at almost any age.

Some are commonly diagnosed during childhood or adolescence. Type 1 diabetes, for example, frequently develops in children and young adults, although it can occur later.

Other autoimmune conditions are more commonly diagnosed during adulthood. Certain autoimmune diseases are particularly common during the reproductive years, while others may first appear later in life.

Age alone cannot rule an autoimmune disease in or out.

What are some new treatments for autoimmune diseases?

Autoimmune treatment is changing rapidly. Researchers are developing therapies that target specific immune pathways rather than broadly suppressing the immune system.

Important areas of research include:

• More targeted biologic medicines
• New oral immune-modifying drugs
• B-cell-directed treatments
• Plasma-cell-targeted therapies
• Precision medicine based on biomarkers
• Cellular therapies
• CAR-T-cell therapy

CAR-T therapy is particularly interesting. Originally developed for cancer treatment, CAR-T approaches are now being investigated for severe autoimmune diseases including lupus, systemic sclerosis and inflammatory myopathies. Early studies have reported deep remissions in some highly selected patients, but most autoimmune CAR-T research remains investigational and early-stage.

This is an exciting area of research, but CAR-T therapy should not currently be presented as a routine cure for autoimmune disease.

How are autoimmune diseases managed long term?

Managing an autoimmune disease is usually a long-term process rather than a one-time treatment.

A good management plan may involve several healthcare professionals depending on the condition, including a physician, rheumatologist, endocrinologist, gastroenterologist, neurologist, dermatologist or immunologist.

Regular monitoring is important because symptoms do not always reflect the amount of underlying inflammation or organ damage.

For example, someone may feel relatively well while a disease is still affecting the kidneys or other organs. Conversely, significant fatigue or pain does not necessarily mean that the autoimmune disease is becoming more dangerous.

When should you see a doctor?

Speak to a doctor if you have persistent or unexplained symptoms such as:

• Ongoing fatigue
• Recurrent joint swelling or stiffness
• Unexplained rashes
• Repeated fevers
• Muscle weakness
• Unexplained weight loss
• Persistent digestive symptoms
• Numbness or tingling
• Dry eyes or dry mouth
• Recurrent mouth ulcers
• Abnormal blood tests
• Symptoms that repeatedly come and go

Early assessment is particularly important when symptoms are persistent, worsening or interfering with normal daily activities.

Frequently asked questions about autoimmune diseases

Are autoimmune diseases contagious?

No. Autoimmune diseases are not contagious and cannot generally be transmitted from one person to another like an infection.

Can you have more than one autoimmune disease?

Yes. Having one autoimmune disease can increase the likelihood of developing another autoimmune condition. This is sometimes referred to as multiple autoimmune syndrome.

Is autoimmune disease hereditary?

Genetic factors can increase susceptibility, but autoimmune diseases are not usually inherited in a simple one-gene, one-disease pattern. Environmental and other factors also contribute.

Is a positive ANA test proof of autoimmune disease?

No. A positive ANA can occur in people who do not have an autoimmune disease. ANA results must be interpreted alongside symptoms, examination and other investigations.

Does autoimmune disease always cause inflammation?

Many autoimmune diseases involve inflammation, but the type and degree of inflammation vary considerably between conditions.

Can autoimmune diseases go into remission?

Yes. Some autoimmune diseases can enter periods of remission, during which symptoms and disease activity become very low or absent. However, remission does not necessarily mean the disease has been permanently cured.

Can lifestyle changes replace autoimmune medication?

Usually not. Healthy lifestyle habits can support disease management, but they should not be used as a substitute for medically indicated treatment.

Should I get an autoimmune blood test if I have fatigue?

Not necessarily. Fatigue has many possible causes. A doctor should first assess your symptoms, medical history and examination before deciding which tests are appropriate.

Final thoughts

Autoimmune diseases are a diverse group of conditions, and there is no single test, treatment or diet that applies to all of them. The first symptoms can be vague, which is one reason diagnosis may sometimes take time.

The most important step is to recognise persistent or unusual symptoms and seek appropriate medical evaluation. Blood tests such as ANA, disease-specific autoantibodies, CBC, ESR and CRP can provide valuable clues, but laboratory results must always be interpreted in the context of the patient’s symptoms and clinical examination.

Although most autoimmune diseases cannot currently be cured, modern treatments can control inflammation, reduce symptoms, prevent complications and, in many cases, help people live full and active lives. Research into targeted therapies and newer approaches such as cellular therapy is also opening exciting possibilities for the future.

Important: This article is for general education and does not replace consultation with a qualified healthcare professional. If you have persistent symptoms or abnormal test results, speak with your doctor for an appropriate evaluation and diagnosis.