Connective Tissue Diseases- SLE Flashcards
What body systems do connective tissue diseases affect?
Can affect any of them
Give 6 examples of connective tissue diseases?
SLE, APS, Sjogren’s, Systemic Sclerosis, Dermatomyositis, Polymyositis
Are connective tissue diseases diseases of connective tissue?
No
Connective tissue diseases are characterised by what?
Spontaneous over activity of the immune system
How quickly do connective tissue diseases come on?
Often evolve over a number of years
What type of disease is SLE?
Chronic autoimmune disease
What are some commonly affected body parts/systems in SLE?
Skin, joints, kidneys, blood cells and nervous system
What type of hypersensitivity reaction is SLE?
Type III- immune complex mediated
Are broken down cells cleared quicker or slower in SLE?
Slower
What is the result of broken down cells being cleared slower in SLE?
The broken down cell contents are seen as foreign and so auto-antibodies are formed against them
Which sex is SLE more common in?
Females
What tends to happen if men get SLE?
This is much less common, but if men do get SLE they will often have much more severe disease
What races is SLE more common in?
Asians, Afro-Americans, Afro-Caribbeans, Hispanic Americans
What are the 4 main factors involved in the aetiology of SLE?
Environmental, genetic, hormonal, immunological
What is the concordance of SLE in monozygotic twins?
40%
If a mother has SLE, what are the chances of her son or daughter getting it?
Son- 1/250 Daughter- 1/40
SLE is associated with what hormone?
Oestrogen
When does SLE usually develop in a woman?
After puberty, at child bearing age (most commonly 20-30)
What is the current 10 year survival rate for SLE?
> 90%
What is mortality in SLE more common to be caused by now?
Immunosuppression from drug side effects CV events
What are some environmental factors which may contribute to SLE?
Viruses (e.g. Epstein Barr), UV light, silica dust
What happens to apoptosis in SLE?
It is increased and defective
What is the auto-antigen in SLE?
Contents of necrotic broken down cells
When someone presents with SLE, what is the most important thing to do and why?
Screen for renal disease because this causes no clinical signs
Where are antibody-antigen complexes deposited?
Basement membranes of skin and kidneys (mesangium)
What do the immune complexes in SLE consist of?
Nuclear antigens and anti-nuclear antibodies
Where do immune complexes form?
Small blood vessels
What happens once immune complexes are in the kidneys?
- Activate complement - Attracts leukocytes - Release cytokines - Inflammation - Necrosis and scarring
What is the SLICC classification for SLE?
4 or more criteria (at least one immunologic and one clinical) OR Biopsy proven lupus nephritis with positive ANA or Anti-DNA
What are the 10 clinical criteria for SLE?
- Acute/chronic cutaneous lupus - Oral/nasal ulcers - Non-scarring alopecia - Arthritis - Serositis - Renal involvement - Neurological involvement - Haemolytic anaemia - Leukopenia - Thrombocytopenia
What is thrombocytopenia?
Low platelets
What is serositis?
Inflammation of the lining of something
What are the 6 immunological criteria for SLE?
- Anti-double stranded DNA - ANA - Anti-Sm - Anti-phospholipid antibody - Low complement - Direct Coomb’s test
When should you not count a direct Coombs test?
In haemolytic anaemia
What are some constitutional features of SLE?
Fever, malaise, poor appetite, weight loss, fatigue
What are the mucocutaneous features of SLE?
- Photosensitivity - Malar rash - Discoid lupus - Non-scarring alopecia - Mouth/nasal ulcers (painless) - Raynaud’s
Where does the SLE malaria rash usually spare?
Naso-labial folds
How long will a lupus rash last for?
A long time once it is established
How would you describe the type of arthritis associated with SLE?
Non-deforming
How can you tell apart rheumatoid arthritis and a lupus arthritis?
RA patients will not be able to make a fist but lupus patients can
What is another MSK feature of SLE, not arthritis?
Increased risk of avascular necrosis of the femoral head (most likely due to steroid use)
What are renal features of SLE?
Proteinuria of > 500mg in 24 hours, red cell casts
What test should always be performed to assess renal function in SLE? If this is positive, what is the next test?
- Urinalysis - Renal biopsy
What are neurological features of SLE?
- Depression - Psychosis - Migraines - Seizures - Neuropathy
What does thrombocytopenia give an increased risk of?
Bleeding
What is important to note about the immunity of SLE patients?
They are very susceptible to infection
What auto-antibody is present in titres of 1:160 in almost all SLE patients?
ANA
Is ANA sensitive, specific or both for SLE?
- Sensitive
What are some other conditions that may have positive ANA?
RA, Hep C, HIV
When should a positive ANA be taken seriously?
If other auto-antibodies are present or the patient has clinical features of a connective tissue disease
What auto-antibody is found in around 60% of SLE patients?
Anti-double stranded DNA
Which auto-antibody is most specific for SLE?
Anti-double stranded DNA
Are titres of anti-dsDNA constant in SLE?
No, they vary with disease activity
The majority of ENA antibodies in SLE are what?
Anti-Ro
What are ENA antibodies usually associated with?
Cutaneous manifestations and secondary Sjogren’s features
What can happen if Anti-Ro/Anti-La are present in a pregnant mother?
- Premature lupus - Foetal heart block
What is the specificity/sensitivity of anti-Sm in SLE?
Low sensitivity Very specific
Anti-Sm antibody in SLE has an association with what?
Neurological involvement
What antibody is found in around 30% of SLE cases and overlaps with features such as skin lesions, Raynaud’s and low grade myositis?
Anti-RNP
A fall in complement levels indicates what?
A flare in disease activity
What are some screening tests that can be done to look for other organ involvement?
- CXR/pulmonary function tests/CT chest - ECHO - Nerve conduction studies - Brain MRI - FBCs
What two things should be used for monitoring of SLE as they vary with disease activity?
- C3/C4 (decrease) - Anti-dsDNA (increase)
What two things should be monitored for CV evaluation?
BP and cholesterol
What drug will all patients with SLE be started on?
Hydroxychloroquine
What is the appropriate dose of steroid for skin rashes, arthritis and serositis?
< 15mg prednisolone/day
What is the appropriate dose of steroid for haematological abnormalities?
0.5mg/kg/day prednisolone
What is the appropriate dose of steroid for severe, resistant changes and major organ involvement?
1mg/kg/day prednisolone
What is the most used immunosuppressant drug in SLE?
Cyclophosphamide
What two biologics may be used in SLE?
- Rituximab - Belimumab
In general, what is the treatment for mild SLE?
Hydroxychloroquine, topical steroids and NSAIDs
In general, what is the treatment for moderate SLE?
Hydroxychloroquine, oral steroids, azathioprine/methotrexate
In general, what is the treatment for severe SLE?
Hydroxychloroquine, IV steroids, cyclophosphamide
What drug is used in cases of SLE which are unresponsive to normal treatment?
Rituximab
What is this clinical sign known as?

Malar (butterfly) rash
What is this clinical sign known as?

Alopecia (non-scarring)
What is this clinical sign known as?

Raynaud’s Phenomenon