week 3- Systemic Lupus Erythematosus (SLE)

Question 1

what is SLE (Systemic Lupus Erythematosus)?

Answer 1

• Chronic inflammatory autoimmune rheumatic disease
• Affects almost any organ, but mainly skin, joints, kidneys,
blood cells and nervous system
• Varied presentation
• Varied severity
• Periods of remission
and relapse (most common reason stress)

Question 2

what is the epidemiology of SLE?

Answer 2

• Relatively uncommon - incidence between 1-8/100,000 in
Europe and North America, higher in Afro-Caribbean
populations
• 90% cases are in women, especially childbearing age
• Highest prevalence in women of Afro-Caribbean origin,
followed by Asians and then Caucasians BUT rarely reported
in Africa, suggesting environmental influences
• Ethnicity affects clinical presentation and autoantibody profile
also

Question 3

what is the aetiology genetically?

Answer 3

• Genetics: Genetic predisposition with 
– increased risk of up to 6 fold with first degree
relative 
– 30% concordance in monozygotic twins 
– Polygenic 
– HLA DQ, DR2 and DR3, A1, B8 
– IRF5 and PTPN22 less common
– Complement mutations

Question 4

what is the aetiology environmentally?

Answer 4

• Hormones: Implicated because increased incidence with
onset of puberty. Estrogen use in postmenopausal women
may increase risk
• Infections: Higher Ab titers to Epstein Barr virus
• UV light exposure: precipitates the disease
• Silica dust and cigarette smoking: increases risk
• Breastfeeding: reduces risk
• Stress: precipitates
• Drug-induced lupus: >80 drugs associated with lupus-like
illness but different to SLE

Question 5

what is the pathogenesis during SLE ?

Answer 5

-start making multiple autoantibodies, you make anti-nuclear antibodies (dsDNA, histones,
ribonuclear components)
– Anti-Cell surface and cytoplasm – red and white blood cells – Anti-Sm (Smith)
• Alteration in T and B cell function
• Increase in interferon secretion
• Circulating immune complexes which damage
the kidney

Question 6

how is SLE diagnosed?

Answer 6

• Highly variable presentation so difficult to
diagnose as can affect almost any organ
• Differentiate from drug-induced lupus (Age, gender,
medication use etc)
• Symptoms
• Urinalysis
• Anti-nuclear autoantibodies – absence excludes SLE
• Blood tests – standard biochemistry anti-Smith,
reduced complement breakdown products of C3,
increased IgM and IgG, decrease IgA
• X-rays and scans of heart, kidney and other organs if
suspected disease

Question 7

what are some signs and symproms of LSE?

Answer 7

• Arthritis – pain in joints and tendons
• Extreme tiredness that doesn’t go away upon rest
• Skin rashes (RED butterfly on face)
• Weight loss
• Oral ulcers
• Swollen glands
• Photosensitivity causing rash on exposed skin
• Poor circulation in fingers and toes (Reynaud’s)
• Involvement of multiple organs

Question 8

what are some symptoms of SLE in the body?

Answer 8

• Renal disorders – abnormal urinalysis
• Haematological disorders – haemolytic
anaemia, leukopenia, thrombocytopenia
• Lungs – shortness of breath, cough
• Neurological Disorders – convulsions,
psychosis, balance problems
• Serositis - inflammation of the lining
membranes

Question 9

what are some complications of SLE?

Answer 9

• artrisits
• GI
• Skin rashes

Question 10

how do you treat SLE?

Answer 10

• NSAIDs
• Steroids
• Hydroxychloroquine – skin, joint involvement and
fatigue
• Immunosuppressants – azathioprine,
methotrexate, cyclophosphamide
• Anti-coagulants if necessary
• Rituximab – anti-CD20 on B cells
• Belimumab- anti-B cell activating factor (BAFF)