Autoimmune diseases

By

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Dr Mai Abolkhair��lecturer of Rheumatology, Rehabilitation and physical medicine�

Learning Objectives

• Describe contributive factors to autoimmune diseases.
• Distinguish organ specific and systemic autoimmune diseases with examples of each.
• Describe the effects of SLE on the body.
• List types of autoantibodies found in SLE.
• Discuss the symptoms of rheumatoid arthritis.
• Describe the characteristics of the Abs found in RA.

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Autoimmune diseases

• Definition:
• Autoimmune diseases occur due to breakdown of mechanisms that maintain autotolerance.

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• Autotolerance: unresponsiveness to self antigens.

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• This means that the body attacks its own cells .

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• By production of autoantibodies and self reactive T cells which cause tissue damage.

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Types:

• Autoimmune diseases are divided into two classes organ specific and systemic:

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• Organ-specific diseases

Immune response is directed against antigens in a single organ;

Addison disease, (autoantibodies attack the adrenal cortex), and

Myasthenia gravis, (attack neuromuscular cells).

- Systemic diseases

The immune system attacks self antigens in several organs such as in

Systemic lupus erythematous

Rheumatoid arthritis

Risk Factors for Autoimmune Diseases.

Genetic and Environmental factors:

Genetic predisposition

• HLA subtypes associated with diseases

Pick an organ ???

Why are autoimmune diseases challenging to diagnose?

• There's usually no single test to diagnose autoimmune disease.

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• Only certain symptoms combined with specific blood markers.

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• Diagnosis can also be difficult because these symptoms can come from other common conditions.

How are autoimmune diseases treated?

• There are no cures for autoimmune diseases, but symptoms can be managed.

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• Some examples of medications used to treat autoimmune diseases include:

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- Corticosteroids.

- Immunosuppressive drugs.

- Biological therapy.

Rheumatoid Arthritis ( RA)

• The most prevalent chronic inflammatory autoimmune disease.

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• The pathological features of synovitis is the hallmark of RA.

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• RA is a systemic disease as may be manifested by generalised weakness, weight loss or low grade fever and extra articular features such as sicca syndrome, nodules and interstitial lung disease.

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Epidemiology of RA

• RA affects approximately 0.5 to 1 % of European and North American adults.

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• prevalence and incidence rates of RA are about two to four times higher in women.

1987 American College of Rheumatology classification criteria for rheumatoid arthritis

At least four of the following criteria :

1. Morning stiffness > 1 h

2. Arthritis of 3 joint areas

3. Arthritis of hand joints

4. Symmetrical arthritis

5. Rheumatoid nodules

6. Serum rheumatoid factor

7. Radiographic changes

2010 ACR/EULAR classification criteria for rheumatoid arthritis (RA)

A. Joint involvement

• 1Large joint 🡪0
• 2-10 Large joints 🡪1
• 1-3 Small joints (with or without involvement of large joints) 🡪2
• 4-10 Small joints (with or without involvement of large joints) 🡪3
• >10 Joints (at least one small joint) 🡪 5

B. Serology

(at least one test result is needed for classification)

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• Negative RF AND negative ACPA 🡪0
• Low positive RF OR low positive ACPA 🡪 2
• High positive RF OR high positive ACPA 🡪3

• C. Acute phase reactants (at least one test result is needed for classification)
• Normal CRP AND normal ESR 🡪 0
• Abnormal CRP OR abnormal ESR 🡪1

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• D. Duration of symptoms
• < 6 Weeks 0
• ≥6 Weeks 1

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• A score of 6 /10 is needed for a definite classification of a patient with RA

• Arthritis

Onset: insidious

Pattern: additive

Number: polyarticular

Symmetry: symmetric

Distribution: small jonts of UL and LL

PAIN: inflammatory

Boutonnière deformity of the ring finger.

Flexion of PIP and Hyperextension of DIP

Swan-neck deformity of the 5th digit.

Hyperextension of PIP and flexion of DIP

Z-shaped deformity of the thumb.

Flexion of MCP and hyperextension of interphalageal joint

Halux valgus deformity

Rheumatoid nodules

X ray hand of RA patient

Systemic lupus erythematosus�

• Autoimmune disease

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• Autoantibody production, immune complex deposition, inflammation, damage

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• Chronic disease, characterized by flares and remission

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• Multisystem involvement

Autoantibodies in Lupus?�

Clinical picture of SLE

Malar rash

Discoid Lesions

Oral lesion

Alopecia

Jaccoud’s arthropathy

Questions ?

Resources

1.USMLE.

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2.primer Rheumatology.

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3.Current Rheumatology.

1)HLA subtypes associated with heumatoid arthritis include :

a) B27.

b)DR4.

c)DR 3.

d)DR 2.

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2) NSAIDs ,disease modifying anti rheumatic drugs (DMARDS) and biological agent are lines of treatement of rheumatoid arthritis:

a) True .

b) False.

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3) Boutonniere deformity in rheumatoid arthritis means :

a) Flexed PIPs ,hyperextended DIPs.

b) Flexed DIPs , hyperextended PIPs.

c) Flexion MCPs, hyperextended PIPs.

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4) Systemic lupus erythematosus is chronic organ specific auto immune disease characterized by remission and flare :

a) True .

b) False.

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Thank you