Systemic Lupus Erythematosis (SLE)

Question 1

what is it?

Answer 1

chronic autoimmune disease
the presentation and disease course of the condition are highly variable (skin, joints, kidney, blood cells, nervous system)

Question 2

pathogenesis (proposed)

Answer 2

defect in apoptosis causes increased cell death
defective clearance of apoptotic cell debris causes persistence of antigen and immune complex production
circulating immune complexes with antigens in various tissues
- in small blood vessels - complement activation and inflammation
- basement membranes of skin and kidneys

Question 3

who gets it?

Answer 3

worldwide prevalence varies
there is an environmental and genetic basis
in the UK black»white though low prevalence in Africa
90% cases in women normally of child bearing age
onset after puberty - 20s-30s

Question 4

what is the prognosis?

Answer 4

mortality decreased over past few decades
currently 10yr survival exceeds 90%
previously mortality was due to the disease itself
now mortality is a result of side effects of medication - infections or CV events

Question 5

constitutional presentation

Answer 5

fever 
fatigue 
weight loss 
pulmonary embolism 
pulmonary hypertension
interstitial lung disease

Question 6

musculoskeletal presentation

Answer 6

arthralgia 
myalgia 
inflammatory arthritis 
arthopathy rarely erosive/ derforming 
AVN (femoral head) - steroid use

Question 7

mucocutaneous presentation

Answer 7

malar rash 
photosensitivity 
discoid lupus
subacute cutaneous lupus 
oral/nasal ulceration 
Raynaud's

Question 8

renal presentation

Answer 8

lupus nephritis

Question 9

respiratory presentation

Answer 9

pleurisy
pleural effusion
pneumonitis

Question 10

haematological presentation

Answer 10

leukopenia
lymphopenia
anaemia
thrombocytopenia

Question 11

neuropsychiatric presentation

Answer 11

seizures
psychosis
headache
aseptic meningitis

Question 12

cardiac presentation

Answer 12

pericarditis 
pericardial effusion 
pulmonary hypertension 
sterile endocarditis 
accelerated ischaemic heart disease

Question 13

Gastrointestinal presentation

Answer 13

autoimmune hepatitis
pancreatitis
mesenteric vasculitis

Question 14

what are the investigations?

Answer 14

no one diagnostic test
FBC may show
- anaemia
- leucopenia
- thromobocytopenia
urinalysis - look for glomerulonephritis
imaging - organ involvement (CT, MRI, echo)

Question 15

antibodies to test

Answer 15

ANA - high sensitivity (>95% of patients) non specific
Anti-dsDNA - sensitivity varies with disease activity - specific
Anti-SM - low sensitivity - specific
c3/4 - low sensitivity when disease is active

Question 16

how is it diagnosed?

Answer 16

constellation of clinical findings
laboratory evidence
use the SLICC classification criteria for systemic lupus erythematous - if >4 criteria (1 clinical and 1 lab) or a biopsy-proven lupus nephritis with positive ANA or anti-DNA
if you diagnose, check glomerulonephritis

Question 17

how is it managed?

Answer 17

depends on its manifestations
skin disease & arthralgia – hydroxychloroquine, topical steroids, NSAIDs
inflammatory arthritis / evidence of organ involvement (pericardial disease, ILD) –
o immunosuppression with azathioprine / mycophenolate mofetil
o corticosteroids at moderate doses for short periods
severe organ disease (lupus nephritis / CNS lupus) – IV steroids, cyclophosphamide
unresponsive cases – IV immunoglobulin, rituximab

Question 18

how is it monitored?

Answer 18

investigated according to symptoms
check regularly (vary with disease activity and warns of a flare)
- anti-dsDNA
- c3/4 levels
urinalysis - blood or protein to check for glomerulonephritis
evaluate and manage CV risk factors - major cause of mortality
- BP
- cholesterol