Systemic Lupus Erythematosus Flashcards
What is systemic lupus erythematosus?
Autoimmune rheumatic disease in which the body’s immune system mistakenly attacks healthy tissue, affecting many systems of the body.
Describe the pathophysiology of SLE.
- Genetic susceptibility combines with environmental triggers to cause apoptosis of cells.
- Products of nuclear degradation are attacked by anti-nuclear antibodies due to decreased immune self-tolerance.
- Antigen-antibody complexes form and cause local inflammation.
Which type of hypersensitivity reactions occur in lupus?
Type 2 and 3 hypersensitivity.
What is type 2 hypersensitivity?
Cytotoxic - the antibodies produced by the immune response bind to antigens on the patient’s own cell surfaces.
What is type 3 hypersensitivity?
Immune complexes (antigen-antibody complexes) are formed and not cleared, causing an inflammatory response and attracting complement.
Which group is SLE most common in? Why might this be?
Women of childbearing age 10:1. This may be due to the effect of estrogen.
What are the diagnostic criteria for SLE?
4 out of 11 from: DOMAPIN(E)RASH - lecture SKIN: Discoid rash Oral ulcers Photosensitivity ARTHRITIS - symmetrical, >2 joints Malar rash IMMUNOLOGICAL disorder (eg anti-dsDNA) NEURO - seizures, psychosis (ESR raised but CRP normal) RENAL - glomerulonephritis ANA SEROSITIS - pericarditis/pleurisy HAEMATOLOGICAL disorder (anaemia, thrombocytopaenia, leukopaenia)
Which marker for SLE has high sensitivity and low specificity?
ANA
Which marker for SLE has high specificity?
Anti-dsDNA
What investigations would you do for suspected SLE and what would they show?
FBC: anaemia (of chronic disease/ autoimmune haemolytic)
ESR raised but CRP normal - very specific.
Auto-abs: Anti-DsDNA, ANA, anti-phospholipid
U&E: urea and creatinine raised in advanced disease
Biopsies - kidney, skin. Deposition of IgG and complement.
Other than SLE, what could cause similar symptoms?
Infection Other AI diseases Malignancy Endocrine disease Metabolic disease
Give 3 environmental triggers of SLE.
Drugs eg hydralazine
UV light
Viruses and bacteria
Give 3 common features of autoimmune rheumatic diseases.
Pathology is inflammation causing scarring and damage in affected organs
Can affect any system and lead to organ failure
Auto-antibodies often present
Damage is irreversible
(lecture 1.2.18)
Give 3 heritable ARDs.
Marfan’s syndrome
Ehler Danlos syndrome
Peyronie’s disease
Give 3 autoimmune ARDs.
Rheumatoid arthritis
SLE
Sjögren’s syndrome
What is anti-phospholipid syndrome?
Presence of anti-phospholipid antibodies with clinical features:
Coagulation defect (need anticoagulation)
Livedo reticularis
Obstetric (miscarriages - seek advice in pregnancy)
Thrombocytopaenia
-20-30% of people with SLE
-Can be primary.
(OHCM)
What is lupus nephritis? How is it diagnosed?
Renal manifestation of SLE. Diagnosed clinically (hypertension, proteinuria, renal failure) and staged histologically using biopsy.
How is lupus nephritis treated?
Class I/II: ACEi/ARB for renal protection, hydroxychloroquine (DMARD) for extra-renal disease.
Class III-IV: immunosuppresion - glucocorticoids, cyclophosphamide, rituximab
Describe the non-pharmacological management of SLE.
- Educate and support - UV protection
- Assessment of disease activity - clinical and immunological, screen for co-morbidities
- Refer - complex cases should involve specialist SLE/nephritis clinics.
Give 3 drugs which can cause SLE.
Anti-TNF agents
Procainamide (anti-arrhythmic)
Hydralazine (anti-hypertensive)
Describe the pharmacological management of SLE.
Immunosuppressive: Hydroxychloroquine (DMARD) Azathioprine, methotrexate Belimumab if disease activity is high Symptomatic: Antidepressants (high rate mental health issues) NSAIDs unless renal disease Reduce CV risk Bisphosphonates for OP
How are skin flares treated in SLE?
Topical steroids
How are mild and moderate flares treated in SLE?
If no organ involvement, hydroxychloroquine or steroids
If organ involvement, DMARDS/mycophenolate.
How are severe flares treated in SLE?
Urgent high-dose steroids, rituximab, cyclophosphamide.
MDT vital
