Systemic Lupus Erythematosus Flashcards
List 5 diseases that come under the category of ‘connective tissue disease’
Rheumatoid arthritis SLE Systemic sclerosis Dermatomyositis/ polymyositis Sjogren’s syndrome
Which gender does SLE more commonly affect?
Females 9:1
Describe the presentation of SLE including 4 specific features.
Malaise, fatigue, weight loss, fever, lymphadenopathy Specific features: Butterfly rash Alopecia Arthralgia Raynaud’s phenomenon
Describe the characteristics of the rash seen in SLE.
Tends to go across the nose
May look like acne
Not painful or itchy
Describe the pathogenesis of SLE.
SLE patients have a defect in apoptosis
Apoptotic cells are not cleared properly so persist + expose their nuclear antigens + autoantibodies are generated against these nuclear antigens
The defect in apoptosis is combined with B cell hyperactivity
Overactive B cells are exposed to the nuclear antigens + plasma cells start to produce autoantibodies that circulate + form immune complexes
Immune complexes deposit in tissues + activate complement leading to inflammation
What is the first investigation performed in the diagnosis of SLE?
Check for anti-nuclear antibodies
not specific for SLE though
What is the pattern of antinuclear antibodies binding to nuclear antigens in SLE?
Homogenous
Antibodies to DNA
What conditions are associated with the presence of anti-Ro and anti-La antibodies? (other than SLE)
Neonatal lupus syndrome
Sjogrens syndrome
Subacute cutaneous lupus erythematosus
What are the biological features seen in SLE? (e.g. in serum)
Increased complement consumption
Anti-cardiolipin antibodies
Lupus anticoagulant
Beta 1 glycoprotein
Describe the haematological features of SLE.
SLE generally associated with low blood counts Lymphocytopenia Normochromic anaemia Leukopaenia Thrombocytopenia Autoimmune haemolytic anaemia
What renal changes might occur in SLE?
Proteinuria
Haematuria
Active urinary sediment
List 4 clinical features that could help pre-empt severe attacks in SLE.
Malaise
Weight loss
Alopecia
Rash
List 3 laboratory markers that could help pre-empt severe attacks in SLE.
Raised ESR
Raised anti-dsDNA antibodies
Increased complement consumption
Describe the differences between mild, moderate and severe disease in SLE.
Mild: skin + joint involvement
Moderate: inflammation of other organs (e.g. pleuritis, pericarditis)
Severe: severe inflammation of vital organs
Describe the treatment of mild disease.
Paracetamol + NSAIDs
Hydroxychloroquine (for arthropathy + cutaneous manifestations)
Topical corticosteroids
Describe the treatment of moderate disease.
Corticosteroids
Start with a HIGH dose + titre downwards
Describe the treatment of severe disease.
Azathioprine: effective steroid-sparing drug, safe in pregnancy
Risk of neutropenia/ BM suppression so needs regular blood monitoring
Cyclophosphamide: used if there is severe organ involvement
Causes BM suppression, infertility, cystitis
What are the following drugs used for and what is their mechanism of action:
Mycophenolate mofetil
Rituximab
Treatment for severe SLE
MM: Immunosuppressive
R: Anti-CD20 antibody, causes depletion of B cells
SLE has and early peak and a late peak in mortality. What are the usual causes of the two peaks?
Early`: renal failure, CNS disease, infection
Late: MI + stroke
What can usually be seen on the blood film of a patient with SLE?
Schistocytes Spherocytes Anisocytosis Poikilocytosis Fibrin strands Thrombocytopaenia Few leukocytes
Describe the appearance of a renal biopsy in a patient with SLE
Proliferative
Crescentic glomerulonephritis
What is principally effected in SLE? What is sometimes also effected?
Joints + Skin
Lungs, Kidneys + Haematology
What genetic deficiencies are associated with SLE?
Complement deficiency C1q + C3
List 4 severe features which may be present in undiagnosed SLE
Psychosis
Renal failure
Accelerated atherosclerosis
Vasculitis
What causes onset of SLE?
Genetic predisposition + Environmental triggers (e.g. virus)
Leads to chronically activated innate immune system,
drives a switch to adaptive immune response, B cell hyperactivity, generation of autoantibodies + immune complexes
What antibodies are seen in the majority of SLE patients?
Anti-dsDNA
What antibodies are seen in ~ 20% of SLE patients, highly specific for lupus?
Anti Sm antibodies
What is the unusual laboratory marker seen in SLE?
CRP stays normal in active disease
