Systemic Lupus Erythematosus profoma

Question 1

Epidemiology of SLE

Answer 1

• More common in Indian &Afro-caribbean people, than caucasians.
• 90% of patients are FEMALE
• peak: 20-30 year

Question 2

Aetiology of SLE

Answer 2

Overexposure to sunlight

oestrogen-containing contraceptive therapy

Infection

stress

Drugs: hydralazine, minocycline

Antiphospholipid syndrome (APS)- characterised by thrombosis & recurrent miscarriages- can occur as primary or secondary condition to SLE

Question 3

Pathogenesis of SLE

Answer 3

• Autoimmune disease - type III hypersensitivity reaction
• Associated w/ HLAB8, HLADR2, HLADR3

Pathogenesis - how does autoimmunity occur?
1. Combination of enviromental & genetic damage causes cell damage.
2. Cell damage due to damaged DNA
3. Cell undergoes apoptosis.
4. Internal proteins are displayed on surface.
5. Normally cleared by phagocytes
6. f apoptotic cells are not cleared efficiently, nuclear material is exposed to immune system (leading to T & B cell activation & autoantibody production).
7. Immune system attacks on own proteins

Question 4

Presentation of SLE

Answer 4

Systemic features:
- mouth ulcers
- fever
- weight loss
- fatigue
- arthralgia- achy, early morning stiffness

Skin:
- Raynauds- purple/ blue discolouration
- photosensitivity- trigged by sunlight
- Livedo reticularis- due to clots in blood vessels so blood pools & veins dilate, forming mottled pattern on skin w/ clear boarders- sign of renal/kidney failure
- malar rash
- discoid rash- raised, round plaques- scaly
- Urticaria- red, itchy weilds (hives)
- non- scaring alopecia

MSK:
- non- erosive arthritis- symmetrical & poly
- tenosynovitis- inflammation of synovial sheath around tendon
- myositis- inflammation of muscles

Cardiovascular:
- Pericarditis - inflammation of pericardium.
- Myocarditis - inflammation of heart muscle.
- Atherosclerosis risk is increased

Antibodies:
- ANA- present in more than 95% of. patients w/ SLE
- +ve for antiphospholipid antibodies = more likely to develop blood clots
- Anti-dsDNA antibody or anti-smith antibody =SLE specific antibodies)

Respiratory:
- Serositis- inflammation of serous tissue of body- pleura, pericardium, peritoneum
- pleural effusion
- increased risk of DVT

Gastro:
- peritoneal serositis- inflammation of peritoneum
- abdominal pain

Neurological:
- seizures
- psychosis

Question 5

Diagnosis criteria for SLE

Answer 5

• Need anti-nuclear antibodies (ANA) positive plus other features of SLE (mentioned above)
• 10 points or more to have lupus.

Question 6

Investigations for SLE: blood tests

Answer 6

Low FBC - haemolytic anaemia, thrombocytopenia (APS), leukopenia.

High ESR - will be high in a flare of SLE.

Low complement (C3 & C4) - lower in active SLE.

High Anti-dsDNA antibodies

Anti-CCP- to exclude RA

Urinanyalysis- to check for proteins/ haemuturia in renal failure or if Livedo reticularis also present

Blood pressure- in case of hypertension- renal disease

For Antiphospholipid syndrome (ASA) -blood tests are needed on 2 occasions, 12-weeks apart to diagnose APS:
- Anti-cardiolipin antibodies.
- Anti-beta2-GPI antibodies.
- Positive lupus anticoagulant assay.
Note - syphilis can cause false positive tests for the above, so should be excluded w/ treponemal serology.

Question 7

Management for SLE: conservative

Answer 7

Avoiding sun exposure e.g. sun cream

Vitamin D supplements

Psychological intervention e.g. as CBT

Question 8

Management for SLE: pharmacological

Answer 8

Mild- moderate disease (skin + joints only)
1. Hydroxychloroquine + Analgesics e.g. NSAIDs
2. Glucocorticoids e.g. prednisolone + Immunosupressants e.g. methotrexate, mycophenolate mofetil (MMF) or azathioprine.
3. Biologic DMARDs - belimumab, rituximab.

NOTE: Severe side effect of hydroxychloroquine is blindness

Severe & life-threatening (organ involvement)
1. High dose glucocorticoids & immunosuppressants
- IV methylprednisolone (10mg/kg IV) + IV cyclosphamide at 2-3 week intervals for 6 cycles.
2. Rituximab may benefit some

Question 9

Management for SLE: monitoring & maintenance

Answer 9

Monitoring:
- ESR
- Complement 4a & 4b

Maintenance:
- Reduce prednisolone
- Keep immunosuppressants e.g. Azathiprine, Methotrexate & MMF

Question 10

Prognosis

Answer 10

• 5 year survival of 95%
• 10 year survival of 92%
• Most common cause of mortality: Cardiovascular disease

Question 11

What causes Raynauds?

Answer 11

vasospasm of small arteries & arterioles > decrease blood flow to the skin.

can be idiopathic or secondary to SLE, Sjogrens

Question 12

What is the management for Raynauds?

Answer 12

1. dihydropyridine calcium channel blockers - first line
2. other options: CE inhibitors and IV prostacyclin

AVOID propranolol - makes it worse!