Lupus Flashcards
What is SLE
Multisystem, autoimmune disorder.
Presents in early adulthood and more common in women and people of Afro-Caribbean origin
General features of SLE
fatigue
fever
mouth ulcers
lymphadenopathy
Pathophysiology
autoimmune disease: SLE a type 3 hypersensitivity reaction
associated with HLA B8, DR2, DR3
thought to be caused by immune system dysregulation leading to immune complex formation
immune complex deposition can affect any organ including the skin, joints, kidneys and brain
Skin features of lupus
- malar (butterfly) rash: spares nasolabial folds
discoid rash: scaly, erythematous, well - demarcated rash in sun-exposed areas.
- Lesions may progress to become pigmented and hyperkeratotic before becoming atrophic
- photosensitivity
- Raynaud’s phenomenon
- livedo reticularis
- non-scarring alopeci
MSK features of lupus
- Arthralgia
- Non-erosive arthritis
Cardiovascular and respiratory features of lupus
- Pericarditis: most common cardiac manifestation
- Myocarditis
- Pleurisy
- Fibrosing alveolitis
Renal features of SLE
- Proteinuria
- Glomerulonephritis- diffuse proliferative
Neuropsychiatric features
anxiety and depression
psychosis
seizures
Antibodies for investigations
99%- ANA positive
20% Rheumatoid factor positive
anti-DsDNA: highly specific (>99%), sensitivity (30%)
Also: anti- U1 RNP, SS-A (anti-Ro) and SS-B (anti-La)
Monitoring of SLE
inflammatory markers
ESR is generally used
during active disease the CRP may be normal - a raised CRP may indicate underlying infection
complement levels (C3, C4) are low during active disease (formation of complexes leads to consumption of complement)
anti-dsDNA titres can be used for disease monitoring (but note not present in all patients)
Drug-induced lupus features
- Arthralgia
- Myalgia
- Skin (malar ras) and pulmonary involvement - pleurisy
- ANA positive in 100%, dsDNA negative
- anti-histone antibodies found in 80-90%
- anti-Ro, anti-Smith positive in 5%
